Grade 10 - Chemistry, Biology, Optics, Climate Change Study Guides.

8/12/2019 Grade 10 - Chemistry, Biology, Optics, Climate Change Study Guides.

1/58

GRADE 10 EXAM UNIT OBJECTIVES 2014


2/58

UNIT 1: CHEMISTRY

Guiding Question: To what extent have understanding chemicals and/or chemical reactions been linked

to human development?

THE ATOM

Protons, neutrons and electrons in atoms and ions from the mass number,

atomic number and charge.

Proton Neutron Electron

Electrical charge Positive Neutral negative

Symbol p+ n e-

Location Nucleus Nucleus Orbit around nucleus

The number of protons is equal to the atomic number of the element. Atoms are electrically neutral so

they have the same number of electrons as protons in each atom. To obtain the number of neutrons,

you subtract the atomic number from the mass number; mass numberatomic number.

Positively charge ion (cation):

Depending on the number with a plus right beside it, on the top right corner of the elements symbol

that will determine the number of electrons the atom will have lost. Subtract this number from the

atomic number and the difference will determine the number of electrons.

Atomic number = number of protons


3/58

Negatively charged ions (anion):

Depending on the number with a minus right beside it, on the top right corner of the elements symbol,

that will determine the number of electrons gained. Add this number to the atomic number and the

sum will determine the number of electrons in the atom.

Atomic number = number of protons

Deduce the electron arrangement for atoms and ions up toZ = 20.

Hydrogen H

Helium He

Lithium Li

Beryllium Be

Boron B

Carbon C

Nitrogen N

Oxygen O

Fluorine F

Neon Ne

Sodium Na

Magnesium Mg

Aluminum Al

Silicon Si

Phosphorus P

Sulfur S

Chlorine Cl

Argon Ar

Potassium K

Calcium Ca


4/58

PERIODIC TABLE

Arrangement of elements in the periodic table in order of increasing atomic

number

An element is a pure substance that cannot be broken down into a simpler chemical substance by anyphysical or chemical means. The elements in the periodic table are arranged in order of increasing

atomic number. The atomic number tells us the amount of electrons and protons in each atom. As you

move down a column of metals, they become more reactive. It is rare that you find metals in their

elemental form.

The way the periodic table is arranged is that the elements that have the same number of valence

electrons in their outermost shell are placed in the same column, in order of increasing atomic numbers

vertically. This is called a group.

Periods of the periodic table tell us how many shells (energy level) the elements in the same horizontalrow have. The members of a period are also positioned after increasing atomic number (from left to

right).

Apply the relationship between the electron arrangement of elements and their

position in the periodic table up toZ = 20.The position of elements on the periodic table is determined by their atomic number and the amount of

valence electrons they have. Elements are put in the same group because they have the same amount of

valence electrons. The number of valence electrons determines how stable and reactive a substance is.

Apply the relationship between the number of electrons in the highest occupied

energy level for an element and its position in the periodic table.As you go across the table the number of electrons in the outermost shell increases.

Group Number

The same as the number of electrons in the outer shell Group 1 = 1 outer shell electron

Period Number

The same as the number of shells in the atom All except the outer shell will be full

Define the term electronegativity.Electronegativity is a number that describes the ability of an individual atom, when bonded, to attract

bonding electrons to itself.


5/58

Trends in atomic radii and electronegativitys for the alkali metals (LiCs)(group 1) and the halogens (F I) (group 7).In LiCs there is a large atomic radius, making the electronegativity decrease because the valence

electrons are far apart and the pull is very weak.Alkali Metals are in the 1st group on the periodic table.

In the 1st group, the atomic radii increases as you go down because each period is a new shell in theelectron. The Alkali metals have the biggest atoms/atomic radii because since there is the least amount

of valence electrons, the protons in the center of the atom dont have as much mass toattract in to

compact the atom. It is easier for them to lose electrons because they are farther away from the nucleus

and so the strength of the force is decreased and the electron can be transferred.

In FI there is a small atomic radius so the valence electrons are closer to the nucleus and the pull is

greater, therefore the electronegativity is high. Halogens are in the 7th group on the periodic table. The

atomic radii increase as you go down, similarly to the alkali metals, because each period is a new shell in

the electron. The halogens have small electrons compared to the alkali metals because they have more

valence electrons for the protons to attract inward.

Trends in atomic radii and electronegativitys for elements across period 3.As the atomic radius increases at the left side, and the electronegativity decreases because there are

less valence electrons and the protons in the centre of the atom dont have as much mass to compact

the atom. When the atomic radius decreases towards the right side, the electronegativity increases

because the amount of valence electrons increase, giving more mass to compact the atom making it

harder for electrons to transfer because the pull is strong.


6/58

Compare the relative electronegativity values of two or more elements based

on their positions in the periodic table.Na and O

Na < 1.7

O > 1.7

O (EN) - Na (EN) = relative electronegativity0.9-3.0=-2.1


7/58

BONDING

Describe the ionic bond as the electrostatic attraction between oppositely

charged ions.

The ionic bond is the electrostatic attraction between oppositely charged ions.The electrostaticattraction between oppositely charged ions, causes them to form a neutral lattice. The charges of the

ions in the lattice will cancel each other out.

Ions have different charges depending on the number of electrons they lose or gain to form a stable

configuration. Ions with a positive charge are called cations, and ions with negative charges are known

as anions.

Ionic compounds are often called salts.

Describe how ions can be formed as a result of electron transfer.


8/58

Deduce which ions will be formed when elements in groups 1, 2 and 3 lose

electrons.Metals tend to lose electrons to form cations (+). Elements in groups 1, 2, and 3 will form cations when

they lose electrons.

Deduce which ions will be formed when elements in groups 5, 6 and 7 gain

electrons.

Non-metals tend to gain electrons to form anions (-). Elements in groups 5, 6 and 7 will form anionswhen they gain electrons.

State that transition elements can form more than one ion.This is referring to the roman numerals that some elements require when bonding because they can

have multiple charges. The transition elements are less predictable than the ones on the far left and

right.

Predict whether a compound of two elements would be ionic from the position

of the elements in the periodic table or from their electronegativity values.Position of the elements

The non-metals occur on the right side of the periodic table. The metals are on the left side. An ioniccompound can only form between a metal and a non-metal.

Electronegativity value

Each atom is assigned an electronegativity value. If the two atoms forming the compound have a

difference in electronegativity of more than 1.7, then their bonding will be ionic


9/58

Describe the lattice structure

Ionic compounds exist in a regular pattern known as a lattice structure. This can

contain millions of ions that extend in all 3 dimensions. There is no fixed

number of ions that can be involved; however the ratio of positive and negative

ions must be the same as the empirical formula to ensure that all the charges ofthe ions cancel each other out.

For the most stable arrangement, cations are packed as closely as possible to

the negative ions, whilst ions of the same charge are as far apart as possible.

This maximises the electrostatic attraction between the ions, while minimizing the repulsion. Many

different arrangements can be generated to do this, which depends on the size of the ions and their

ratio. It will result in the lattice structure of that compound.

Describe the covalent bond as the electrostatic attraction between a pair of

electrons and positively charged nucleiOuter shell electrons interact and rearrange themselves in to amore

stable arrangementthat has lower chemical energy.

The positively charged nucleus of an atom is attracted to the

negatively charged electrons. When two atoms come together to

form a covalent bond, the positively charged nuclei will be attracted

to the electron pairs of the other atom.

However there is repulsion between all the electrons as they have

the same charge. The same is true for the positively charged nuclei,

which also repel each other.

To maintain a covalent bond, a balance must be achieved between attraction and repulsion.

A molecule can be defined as a discrete group of non-metal atoms covalently bonded to one another.

Molecules contain atoms in a set ratio.

Describe how the covalent bond is formed as a

result of electron sharing


10/58

Predict whether a compound of two elements would be covalent from their

position in the periodic table or form their electronegativity values.

Position in the periodic table:

a covalent bond is between a non-metal & non-metal

Electronegativity:

a difference of electronegativity values is less than 1.7

Describe how the covalent bond is formed as a result of electron sharing

There is a significant overlap of the atomic radii when a covalent bond is formed.

As the two atoms approach each other electrostatic attractions and repulsions occur between the nuclei

and electrons. Covalent bonding is made up of from shared pairs of electrons, one or more, each from

the binding atom. When only one pair occupies the space between electrons, this is a single covalentbond. This sharing of electrons allows each of the atoms to fill their outer shells.

Deduce the Lewis structure of molecules and ions for up to four electron pairs

on each atom

This can be done using dots, lines or crosses.

All the valence electrons are drawn, as they form part of the bonding. They are used to show how full

outer shell is obtained. In Lewis structures, the valence electrons are represented by dots and crosses,

distinguishing between the different elements electrons.

All group 7 elements and hydrogen form diatomic molecules. There are only two atoms bonded to fill

the outer shell for these elements. In chlorine, which has 7 valence electrons, has a single bond:


11/58

Group 6 elements, have six valence electrons so they must be sharing another two electrons to

complete a full outer shell. For the diatomic molecule O2, a double bond is formed to fill its shell.

Predict whether a compound of two elements would be covalent from the

position of the elements in the periodic table or from their electronegativity

values.Molecular elements are made up of more than one atom of the same element covalently bonded.

Molecular compounds are made up of two or more non-metals covalently bonded. Molecular

compounds are made up of covalent bonds with differences in electronegativity that are less than 1.7.

Compare and explain the properties of substances resulting from different types

of bonding. (Including melting and boiling points, electrical conductivity andsolubility in water)Molecular compounds exist as solids, liquids and gases at room temperature. Some are soft and

malleable, other hard and brittle, they are quite varied. They have relatively low melting and boiling

points and many do not dissolve easily in water.

Ionic compounds are solid at room temperature and hard and brittle. They have relatively high melting

and boiling points and conduct electricity as molten liquids. They are strong electrolytes, which means

that it separates into ions when it dissolves in water, producing a solution that conducts electricity.

Electrolytes are acids bases or ionic compounds that separate into ions when they dissolve in water and

produce a solution that conducts electricity. They are free floating ions in water so electricity can flow

easily through them.

H O F BR I N CLo Used when its a single element in balancing an equation, but when it happens to be a

HOFBRINCL, you put a 2 in the subscript

o If its not a HOFBRINCL, you leave it as is, and dont put anything in the subscript, just thesymbol


12/58

CHEMICAL REACTIONS

Define physical and chemical properties of matter. Identify examples.

Physical Property: a description of a substance that does not involve forming a new substance; for

example, colour, texture, density, smell, solubility, taste, melting point, and physical stateChemical Property: a description of what a substance does as it chances into one or more new

substance(s).

Chemical Property Example

Reaction of an acid with a base Vinegar reacts with baking soda to produce

carbon dioxide gas

Flammability Gasoline burns easily if ignited

Bleaching ability Hydrogen peroxide breaks down the pigment

(colour) in hair

Corrosion Discarded batteries in landfill sites break down

readily when they come in contact with

groundwater

Using the periodic table of elements; be able to name ionic, polyatomic and

molecular compounds.

Ionic compounds:

1. metal ion (as is)2. non-metal ion (ending changes to ide)

Example:

MgCl2

magnesium chloride

NaClsodium chloridePolyatomic compounds:

1. Write the name of the metal (as is) (*check to see if it has more than one ionic charge)2. Write the name of the compound

Example:

Na2CO3sodium carbonate Ca(OH)2calcium hydroxide

Molecular compounds

1. Name both elements in the order that they appear (usually right most element on right, leftmost element on left)

2. Write the ending of the second element to ide3. Add prefixes to each element (the prefix mono is never added to the first element)

Example:

SO2sulfur dioxide


13/58

Using the periodic table of elements; be able to write formula for ionic,

polyatomic and molecular compounds.

Ionic compounds:

1. Write the symbols of the elements (metal first)2.

Add the ionic charge of each element

3. Criss-cross the ionic charges so that they become subscripts4. Rewrite the formula with the numbers (no charges)

Example:

Magnesium and chlorineMgCl2 Magnesium and SulfurMgS

Polyatomic compounds:

1. Write the symbols and charges for each ion2. Criss-cross the charges and write them as subscripts without charges3. Rewrite the formula with the numbers (no charges)

Example:

Calcium HydroxideCa(OH)2

Molecular compounds:

1. The prefixes of the name of the elements indicate the number of atoms of each elementExample:

diphosphorus pentoxideP2O nitrogen trioxideNO3

Deduce balanced chemical equations when all reactants and products are given

Chemical equations are shorthand representations of compounds. Chemical reactions are represented

by equations using the chemical formulas and symbols of the substance involved in the reaction.

Chemical equations use chemical formulas to represent the word equation and include the different

states of the compounds.

Word equation

Potassium + waterhydrogyn + potassium hydroxide

Chemical equation

K + H2OH2 + KOH


14/58

When writing out these, the Law of Conservation must be taken in to account. The Law of Conservation

states that matter can neither be created nor destroyed, it can only be changed from one form to

another. In the case of chemical equations, that means there must be the same number of every type

of atom on both sides of the equation. All that happens in a chemical reaction is that the bonds in the

reactants break, the atoms rearrange, and bonds between the products are formed. Therefore to

reflect this, all chemical reactions must be balanced. We do this by adding integer coefficents to the

chemical formulas, except, in case of 1.

Apply the state symbols (s), (l), (g) and (aq).The state symbols in brackets show the physical state of the substance at the reaction temperature.

Solid (s), liquid (l), gas (g), or dissolved in water (aq).

For Example:The complete equations in words and symbols would be;

potassium + chlorine potassium chloride.

2K(s) + Cl2(g) 2KCl(s)

lithium + oxygen lithium oxide.

4Li(s) + O2(g) 2Li2O(s)

Identify 6 main types of chemical reactions as; synthesis, decomposition, single

displacement, double displacement, neutralization and combustion.

Synthesis Reaction: two simple reactants combine to make a larger or more complex product. The

chemical equation is: A+ABABDecomposition Reaction: a reaction in which a large or more complex molecule breaks down to from

two (or more) simpler products.

The chemical equation is: ABA+BSingle Displacement Reaction: a reaction in which an element displaces another element in a compound,

producing a new compound and a new element.

The chemical equation is: A+BCAC+BDouble Displacement Reaction: a reaction that occurs when elements in different compounds displace

each other or exchange places, producing two new compounds.The chemical equation is: AB+DCAD+CBCombustion: the rapid reaction of a substance with oxygen to produce oxides and energy; burning.

The chemical equation is: CXHy+O2CO2+H2ONeutralization: a chemical reaction in which an acid and a base react to form an ionic compound (a salt)

and water; the resulting pH is closer to 7.

The chemical equation is: Same as Double Displacement.


15/58

Predict the products of the 6 main types of chemical reactions studied in class

when the reactants are given1. write the chemical equations of the given reactants2. using the general chemical equations of the main types of chemical reactions, match the

chemical equation of the reactants with the general chemical equation of the reactions

_2_Mg + O2_2_MgO

NaCl + AgNO3AgCl + NaNO3

Mg + _2_AgNO3_2_ Ag + Mg(NO3)2


16/58

ACIDS AND BASES

Define acidsand basesAcids are hydrogen ion (H+) donors

Bases are hydrogen ion (H+) acceptors (NH3)

Outline the characteristic properties of acids and bases in aqueous solution.Acids: produce H+(as H3O+) ions in water

HCL(aq)H+

(aq) +ML-(aq)

Produce a negative ion (-) too

Taste sour

Corrode metals

React with bases to form salts and water

React with Metals

Bases: produce OH-ions in water

Taste bitter and chalky

Are electrolytes

Feel soapy and slippery

Distinguish between aqueous solutions that are acidic, neutral or alkaline using

the pH scale.The pH scale is used to give a scale of how acidic or alkaline a solution is based on the concentration of

H+ions in a solution. Any solution with a pH of less than 7 is acidic. A solution with a pH of 7 is neutral,

and a solution with a pH of more than 7 is an alkaline.


17/58

Identify which of two or more aqueous solutions is more acidic or alkaline using

pH values.

When two solutions are compared, the one with the smaller pH value is more acidic and the one with

the larger pH value is more alkaline. In order to determine pH, indicator substances or pH meters can be

used.

Universal indicator

If the indicator paper is used, the pH is determined based on the colour the paper turns when placed in

the solution. Different indicators can be used to accurately determine the pH, although the problem

arises that people interpret colours differently. Alternatively, indicator solution can be dropped into the

solution, allowing the entire solution to change colour. The pH is likewise determined by the new colour

of the solution.

pH Meter

This reads the concentration of H+ions through an electrode, giving the pH with an accuracy of a few

decimal points. This method is more accurate than universal indicators.

State that each change of one pH unit represents a 10-fold change in the

hydrogen ion concentration [H+(aq)].

The concentration of H+ions in a solution and the pH of the solution have an inverse relationship. A

change of one pH unit equates to a ten-fold change in [H+] because the scale is logarithmic. If the pH

increases, the [H+] decreases, and vice versa.

pH = -log [h+]

1 = 1.0 H+ ions

2 = 0.1 H+ ions

3 = 0.01 H+ ions

4 = 0.001 H+ ions

Deduce changes in [H+(aq)] when the pH of a solution changes by more than

one pH unit.When a solution changes by more than one pH unit, it gets either 10 times more or less acidic.


18/58

UNIT 2: BIOLOGY

Guiding question: To what extent do individual choices impact the way systems interact?

State and explain the structures and associated functions of mentioned cell

parts in both plant and animal cells

Cell wall (plant cell):

found only in the cells of plants, fungi, and someunicellular organisms

they provide support for the cell because they aremade of a tough material called cellulose

Cell membrane (plant + animal cell):

the cell membrane surrounds and protects thecontents of cells

it is the structure that controls the movement ofsubstances in a and out of the cell

Cytoplasm (plant +animal cell):

jelly-like substance that is constantly moving insidethe cell

helps distribute materials such as oxygen and food tothe different parts of the cell

provides support for the organelles inside the cell

Nucleus (plant + animal cell):

the nucleus controls the cell activities

contains chromosomes (structures made of geneticmaterial that directs cells growth and reproduction)

the nucleus is enclosed in a nuclear membrane,which controls what enters and leaves the nucleus


19/58

Ribosomes (plant +animal cell):

organelles that manufacture proteins ribosomes are the small dots on the endoplasmic

reticulum

Endoplasmic reticulum (plant + animal cell):

folded membrane that forms a system of internalcanals within the cytoplasm that are used for

transportation within the cell

the rough endoplasmic reticulum contains protein-manufacturing ribosomes

Explain cell organization by describing the links between cells, tissues, organs,

and systems in the human body

Multicellular organisms have the following 5 levels of organization ranging from simplest to most

complex

Cells

o Are the basic unit of structure and function in living things.o May serve a specific function within the organismo Examples- blood cells, nerve cells, bone cells, etc.

Tissues

o Made up of cells that are similar in structure and function and which work togetherto perform a specific activity

o Examples - blood, nervous, bone, etc. Humans have 4 basic tissues: connective, epithelial,muscle, and nerve.


20/58

Organisms

o Made up of tissues that work together to perform a specific activityo Examples - heart, brain, skin, etc.

Organ Systems

o Groups of two or more tissues that work together to perform a specific function for theorganism.

o Examples - circulatory system, nervous system, skeletal system, etc.o The Human body has 11 organ systems - circulatory, digestive, endocrine, excretory

(urinary), immune (lymphatic), integumentary, muscular, nervous, reproductive, respiratory, and

skeletal.

Organisms

o Entire living things that can carry out all basic life processes. Meaning they can takein materials, release energy from food, release wastes, grow, respond to the

environment, and reproduce.

o Usually made up of organ systems, but an organism may be made up of only onecell such as bacteria or protest.

o Examples - bacteria, amoeba, mushroom, sunflower, human

Define cell, tissue, organ, organ system

Cell: The smallest structural and functional unit of an organism, typically microscopic and consisting ofcytoplasm and a nucleus enclosed in a membrane. Microscopic organisms typically consist of a single

cell, which is either eukaryotic or prokaryotic.

Tissue: A group of specialized cells

Organ: a structure composed of different tissues working together to perform a complex body function.

Organ System: a system of one or more organs and structures that work together to perform a major

vital body function such as; digestion or reproduction


21/58

Explain the importance of the surface area to volume ratio as a factor limiting

cell size.

o cell needs a large surface area in order to carry out metabolic functions (as chemical reactionsrequire a surface). As a cell grows, it needs to carry out more and more reactions. Therefore,

since a cell has to maintain a certain surface area to volume ratio, its size is limited.

o The rate of exchange of materials (nutrients/waste) and energy (heat) is a function of its surfacearea.

o Thus: As a cell grows in size (volume), the distance increases between the cytoplasm at thecenter of the cell and the cell membrane. The rate of chemical exchange with the surrounding

environment may hence become too low to maintain the cell. It is not able to excrete waste

quickly enough or take in important minerals.

Volume of a cell determines requirements while surface area determines supply.

Outline the stages in the cell cycle, including interphase (G1, S, G2), mitosis and

cytokinesis.

Interphase:

1. Growth 12. Synthesis3. Growth 2

Mitosis:

1. Prophase2. Metaphase3. Anaphase4. Telophase

Cytokinesis


22/58

State that interphase is an active period in the life of a cell when many

metabolic reactions occur, including protein synthesis, DNA replication and an

increase in the number of mitochondria and/or chloroplasts

The cell spends the largest percentage of its time in interphase. Interphase is an active period in the life

of a cell when many metabolic reactions occur, including protein synthesis, DNA replication and anincrease in the number of mitochondria and/or chloroplasts. Through gene expression and protein

synthesis there is a specialisation of cell structure and function. During this interphase the cell carries

out growth, cellular respiration, and any specialized functionsof that cell type. The length of the

interphase varies from one type of cell to another.

G1: follows cytokinesis. The cell is involved in the synthesis of various proteins which allow thecell to specialise.

S-phase:involves thereplication of DNA molecules which takes place prior to the phases ofmitosis.

G2:growth occurs as cell prepares to divide, which also involves the replication of mitochondriaand in the case of plants, the chloroplast

State that the cell spends the largest percentage of its time in interphase.

Cells spend the most time in interphase (no division is happening). In the center is the nucleus

which holds the DNA.

Describe the events that occur in the four phases of mitosis (prophase,

metaphase, anaphase and telophase).

Mitosis is a process that allows a cell to copy itself and dividemaking new cells.
http://click4biology.info/c4b/3/Chem3.4.htmhttp://click4biology.info/c4b/3/Chem3.4.htm


23/58

Prophase:

o The nuclear envelope that holes DNA in the nucleus breaks down anddisappears. This happens so the genetic material can be expanded and

copied.

o The DNA will condense to form chromosomeso Anchors called centrioleswill appear to hold the spindle.o The spindle is a thread-like fiber that will attach to each chromosome at

its center.

o The spindle helps pull each side of the sister chromatid to opposite sides.

Metaphase (middle)

o The chromosomes are about to move to opposite sides for cell division.o They must line up so they can divide perfectly in half.o Easy to spot because the lining up of chromosomes appear like little xs in

the center of the cell.

Anaphase (away)

o Ripping apart of the chromosomeso They begin to migrate as they are pulled by the spindle to the centrioles.o You no longer see the x shape of the chromosomes, rather half of one.o He genetic material is now split into two identical partso Each side of the cell will have one copy

Telophase

o Opposite of prophaseo Nuclear membrane reappears and surrounds DNA as it condenses into

chromatin

o Centrioles and spindle will disintegrate and disappearo The cell will now be nearly ready for divisiono It is now clear that there are almost two cells, each identical


24/58

State that growth, embryonic development, tissue repair and asexual

reproduction involve mitosis.

Growth

Multicellular organisms increase their size through growth. This growth involves increasing the number

of cells through mitosis. These cells will differentiate and specialise their function.

Embryonic development

When the fertilised egg cell (zygote) divides to form the multicellular organism. Each cell in the

organisms is identical (genetically) to all the other cells. However, each cell will express only a few of its

genes to determine its overall specialisms, a process called differentiation. In this way a stem cell may

become a muscle, or it may become a nerve cell or any one of the many different kinds of cells found in

a complex multicellular organism.

Tissue Repair

As tissues are damaged they can recover through replacing damaged or dead cells. This is easily

observed in a skin wound.

Asexual Reproduction

This the production of offspring from a single parent using mitosis. The offspring are therefore

genetically identical to each other and to their parent- in other words they are clones.

State that tumours are the result of uncontrolled cell division and that these can

occur in any organ or tissue.

Tumors are formed when cell division goes wrong and is no longer controlled. This can happen in

any organ or tissue.

Distinguish between a malignant and a benign tumour.

A tumour is a mass of cells that continue to grow and divide without any obvious function in the

body.

Malignant: a tumour that interferes with the functioning of surrounding cells; a cancerous tumors.

Benign: a tumour that does not affect surrounding tissues other than by physically crowding them


25/58

Define carcinogen.

o Any environmental factor that causes cancero

Tobacco smoke; radiation, such as X-rays and UV rays from tanning beds and sunlight; someviruses such as, HPV and hepatitis B; certain chemicals in plastics; and many organic solvents.

State that the goal of cancer treatment is to slow down the growth of the

tumours or destroy as many cancer cells as possible

The goal of cancer treatment is to slow down the growth of the tumors or destroy as many cancer cells

as possible. There are currently 3 main conventional methods of treating cancer: surgery,

chemotherapy, and radiation therapy. A cancer treatment plan may consist of one or a combination of

these methods.

State and describe three types of cancer treatments; radiation, surgery,

chemotherapy.

Surgery

o Physically removing he cancerous tissueso Only possible if the tumour is easily accessible and fairly well defined

Chemotherapy

o Treating cancer using drugso Slows or stops the cancer cells from dividing and spreading to other body parts by killing the

cells

o The drugs can be injected or orally (by mouth)o Side effects: hair loss, nausea and fatigueo Its aim is to shrink a tumour for surgical removal or for radiation treatmentso The drug travels throughout the body and reaches almost all tumours

Radiation

o Cancer cells are easily damaged by ionizing radiation because they divide rapidlyo Radiation therapy takes advantage of thiso The DNA of many daughter cells are damaged by the radiation, so the cells cannot divide furthero Radiation is directed at the tumour by using a focused beam or implanting a radioactive source

into the tumour; minimizes side effects


26/58


27/58

Outline the structures and respective functions of the human digestive system.

Organ Role in Digestion

mouth

o Begins break down of food.o Creates a softened, moistened mass (called a bolus) that can easily be

swallowed

o Saliva moistens food Contains salivary amylase to begin digestion of carbohydrate

esophagus

The part of the alimentary canal that

connects the throat/mouth to the stomach

There are two processes in the esophagus

that help digest food:

Peristalsiso moves food at variable rates

along the digestive tract

o According to the Mayo Clinicit takes food roughly 50

hours in adults and 33 hours

in children.

Segmentationo simultaneous circular fiber contractions at several separate points

along the digestive tract

stomach

o Liquefies meal with the help of HClo No digestion of carbohydrates or fat; some

protein digestion

o Slowly releases thick liquid (chyme) into thesmall intestine

o Very little absorption

liver

o Secretes bile, which is a chemical needed to break down lipids/fats, into thesmall intestine

gall bladder o Stores bile

pancreas

o secretes pancreatic lipase which further aids in the breakdown of lipids secretes bicarbonate (to neutralize acidic chyme) into intestine secretes proteases (which function at neutral pH) to break down

o proteins in the small intestine secretes insulin to regulate blood sugar


28/58

secretes pancreatic amylase to continue breaking downcarbohydrates

small

intestine

~ 6-9 meters in length

o Here is where digestion is completed with the help of the pancreas, gallbladder and liver

o Almost all absorption is completedo Small intestine is divided into three sections

Duodenum Jejunum Ileum

Absorption of nutrients

The majority of nutrient absorption occurs in the duodenum mainly due to the villi

and the microvilli found on the lining

The villi structures massively increase thee SA of absorption, bringing moreof the gut in contact with the products of digestion

The epithelium (surface layer of the villi) are also covered in microvilli Every villus also has an excellent network of capillaries that allow the end

products of digestion to be absorbed quickly in to the bloodstream

large

intestine

~ 1-2 meters long

o Secretes mucusprotects from mechanical damage, lubricates masso Absorbs some water & salts

rectum

o Used for storage of feceso Distention of rectum elicits defecation reflex (anal sphincter under

voluntary control)

o Feces: bacteria, dead cells, salts, bile pigments, indigestible cellulose, wateranus

o Is the final opening through which digested materials pass


29/58

Label a diagram of the digestive system

Explain how the structure of the villus is ideally suited to its role in absorption

and transport of the products of digestion.

The majority of nutrient absorption occurs in the duodenum mainly due to the villi and the microvilli

found on the lining. The structure of the villus is very specific. Firstly there is a great number of them so

this increases the surface area for absorption in the small intestine. In addition the villi also have their

own projections which are called microvilli. The many microvilli increase the

surface area for absorption further. These microvilli have protein channels and

pumps in their membranes to allow the rapid absorption of food by facilitated

diffusion and active transport. Also, the villi contains an epithelial layer which is

only one cell layer thick so that food can pass through easily and be absorbed

quickly. The blood capillaries in the villus are very closely associated with the

epithelium so that the distance for the diffusion of the food molecules is small.

This thin layer of cells contains mitochondria to provide the ATP needed for the

active transport of certain food molecules. Finally, there is a lacteal branch at the

center of the villus which carries away fats after absorption.Summary

1. Many villi increase the surface area for absorption.2. Epithelium is only one cell layer thick and so food is quickly absorbed.3. Microvilli on the villi increase the surface area for absorption further.4. Protein channels and pumps are present in the microvilli for rapid

absorption.

5. The mitochondria in the epithelium provide ATP needed for active transport.


30/58

6. Blood capillaries are very close to the epithelium so diffusion distance is small.7. The lacteal takes away fats after absorption.

State that the three main parts of the circulatory system are the blood, heart,

and blood vessels.

The three main parts of the circulatory system are the blood, heart, and blood vessels. The heart

pumps the blood through large blood vessels, called arteries, which branch into smaller capillaries.

In the capillaries, blood exchanges many substances with the surrounding tissue. After this

exchange, blood flows into larger blood vessels called veins and eventually returns to the heart.

State the function of the circulatory system.

The function of the circulatory system is to transport substances around the body. It moves nutrients

absorbed from the intestine to all of the bodys cells.

o Blood flows through the lungs to pick up oxygen and then flows through the body to deliver itto active cells

o Blood also carries wastes from the body tissues for disposal. It carries carbon dioxide to thelungs, where it is released into the air

o Other waste substances are carried to the kidneys, the substances are filtered out and excreted.The other vital functions of the circulatory system are the regulation of body temperature and the

transport of disease-fighting white blood cells to areas of the body where there are viruses or bacteria.

Organ Role in Circulation

erythrocytes

Red Blood Cells (erythrocytes)

o primary function is to carry oxygeno proteins on the surface of the RBC determine a persons blood type (A, B, AB,

or O)

leucocytes

White Blood Cells (leucocytes)

o responsible for helping defend the body from disease and infection

thrombocytes

Platelets (thrombocytes)

o responsible for blood clottingplasma

o is the liquid component of the bloodo it is composed mostly of water, but also contains blood proteins and

electrolytes

arteries

o Blood is pumped AWAY from the heart in thick walled vessels calledARTERIES

o transport blood under high pressure throughout the body

veins

o Blood is pumped TO the heart in thin walled vessels called VEINS have valves that allow blood to flow in one direction


31/58

capillaries

o Connect the arteries to the veinso Narrowest of all blood vessels

RBC travel through in single file Walls are one cell layer thick

o Single file and thin walls ensures RBCs travel at slow speeds and allows themto pick up and unload carbon dioxide & oxygen by diffusion

o Branching in capillaries means there is a large surface area for diffusion

heart

The Heart

o The heart is a muscular organ that functions primarily as a pumpo It has chambers to receive and deliver bloodo It has valves that direct the flow of blood through the chamberso Your heart is about the size of a clenched fist

Blood Supply To the Heart

o The heart is no different from every other muscle in your bodyit constantlyrequires a fresh supply of oxygen


32/58

o Coronary circulationdelivers oxygenated blood directly to the heart tissueso Diseasein the coronary arteries prevents the heart from receiving enough

oxygen

o The sudden blockage of a coronary artery can cause aheart attack

Blood Flow

through the

Heart

o Blood returns from systemic circulation,through the superior & inferior vena cava, to

the right atrium

o Blood then passes to the right ventricle whichcontracts to send blood through the pulmonary

arteries to the lungs

o After picking up oxygen in the lungs, bloodflows through pulmonary veins back to the left

atrium of the heart

o Blood then travels into the left ventricle, whichcontracts to pump blood through the aorta to

the rest of the body

right atrium o Blood returns from systemic circulation, through the superior & inferior venacava, to the right atrium

left atrium o After picking up oxygen in the lungs, blood flows through pulmonary veinsback to the left atrium of the heart

right ventricle o Blood then passes to the right ventricle which contracts to send bloodthrough the pulmonary arteries to the lungs

left ventricle o Blood then travels into the left ventricle, which contracts to pump bloodthrough the aorta to the rest of the body


33/58

atrio-ventricular

valves

(AV valves)

o The rightatrioventricular (AV) valve, controls the flow of blood between theright atrium and the right ventricle

o The leftatrioventricle (AV) valve controls the flow of blood between the leftatrium and the left ventricle

pulmonary

semi-lunar valve

o The pulmonary semilunar valve controls the flow of blood between the rightventricle and pulmonary vein

aortic semi-lunar

valve

o The aortic semilunar valve controls the flow of blood between the leftventricle and the aorta

Aorta o The main artery of the body, supplying oxygenated blood to the circulatorysystem. In humans it passes over the heart from the left ventricle and runs

down in front of the backbone.

vena cavao A large vein carrying

deoxygenated blood into

the heart.

o There are two in humans,the inferior vena cava

(carrying blood from the

lower body) and the

superior vena cava (carrying

blood from the head, arms,

and upper body).


34/58

Describe the flow of blood through the heart

The right and left sides of the heart work together

Right Side

Blood enters the heart through two large veins, the inferior and superior vena cava,

emptying oxygen-poor blood from the body into the right atrium.

Left Side

The pulmonary vein empties oxygen-rich blood, from the lungs into the left atrium.

Atrial contraction

Right Side

Blood flows from your right atrium into your right ventricle through the open tricuspid

valve. When the ventricles are full, the tricuspid valve shuts. This prevents blood fromflowing backward into the atria while the ventricles contract (squeeze).

Left Side

Blood flows from your left atrium into your left ventricle through the open mitral valve.

When the ventricles are full, the mitral valve shuts. This prevents blood from flowing

backward into the atria while the ventricles contract (squeeze).

Ventricular contraction

Right Side

Blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the

lungs.Left Side

Blood leaves the heart through the aortic valve, into the aorta and to the body. This

pattern is repeated, causing blood to flow continuously to the heart, lungs and body.


35/58

Distinguish between arteries, veins, and capillaries.

Arteries, veins, and capillaries are the three types of blood vessels that form a network of tubes

throughout the body to transport blood.

Artery

o Thick-walled blood vessel that carries blood away from the hearto Because the blood in the arteries is being pumped away from the heart, and it is under greater

pressure than the blood in other blood vessels

o The walls of the arteries are thicker in order to withstand this pressureVein

o A blood vessel that returns blood to the hearto Blood is at a lower pressure, so the walls of the vein are not as thicko Arteries and veins are largest near the heart, where just a few blood vessels carry large volumes

of blood. Further from the heart, the blood vessels are much smaller, and there are more of

them

o Arteries and veins are linked together by the capillariesCapillary

o A tiny, thin-walled blood Bessel that enables the exchange of gases, nutrients and wastesbetween the blood and the body tissue

Define blood and state a description of the four components of blood

Blood is a type of connective tissue that circulates throughout all parts of your body. The blood consists

of four components;

Red Blood Cells (erythrocytes)

o Primary function is to carry oxygeno Proteins on the surface of the RBC determine a persons blood type (A, B, AB, or O)o Contain a protein called hemoglobin which allows it to transport oxygeno Hemoglobin makes it appear red

White Blood Cells (leucocytes)

o Responsible for helping defend the body from disease and infectiono Recognize and destroy invading bacteria and viruseso Make up less than 1% of the volume of bloodo Only blood cells that have a nucleus


36/58

Platelets (thrombocytes)

o Responsible for blood clottingo Also compromise less than 1% of the blood

Plasma

o Is the liquid component of the bloodo It is composed mostly of water, but also contains blood proteins and electrolyteso Makes up over half the volume of blood

Explain how heart attack, arteriosclerosis and stroke occur.

Heart Attack

o During a heart attack, a clotcompletely blocks a coronary artery and there is death of cardiaccells

o Symptoms: fatigue, dizziness, indigestion, chest paino Risk Factors:increasing age, smoking, poor diet, obesity lack of exercise, stress, family, history

of heart diabetes

Stroke

o Occurs when a blood vessel leading to the brain is damagedo A clot forms in the vessel, or the vessel bursts due to high blood pressureo Symptoms depend on the vessel involved and the part of the brain affected (opposite side of

the body)

o Symptoms: weakness, slurred speech, numbnesso Some symptoms are reversible with time, others may be permanent

Arteriosclerosis

o Hardening and narrowing of the arterieso Usual cause of heart attacks, strokes, and peripheral vascular disease -- what together are called

"cardiovascular disease."

Explain the need for a ventilation (respiratory) system.A ventilation system is needed to maintain the concentration gradients of gases in the alveoli. Diffusion

of gases occurs due to the concentration gradient of oxygen and carbon dioxide between the alveoli and

the blood. The body needs to get rid of carbon dioxide which is a product of cell respiration and needs

to take in oxygen as it is needed for cell respiration to make ATP. There must be a low concentration of

carbon dioxide in the alveoli so that carbon dioxide can diffuse out of the blood in the capillaries and

into the alveoli. Also there must be a high concentration of oxygen in the in the alveoli so that oxygen

can diffuse into the blood in the capillaries from the alveoli. The ventilation system makes this possible

by getting rid of the carbon dioxide in the alveoli and bringing in more oxygen.

Summary:

1. To maintain the concentration gradients of oxygen and carbon dioxide in the alveoli.2. The body needs oxygen to make ATP via cell respiration.3. The body needs to get rid of carbon dioxide which is a product of cell respiration.4. Oxygen needs to diffuse from the alveoli into the blood. Carbon dioxide needs to diffuse from

the blood into the alveoli.

5. To do so there must be a high oxygen concentration and a low carbon dioxide concentration inthe alveoli.

6. A ventilation system makes this possible by getting rid of the carbon dioxide in the alveoli andbringing in more oxygen.


37/58

Outline the structures and respective functions for all parts of the human

respiratory system.

Organ Role in Respiration

nose

o the part projecting above the mouth on the face of a person or animal,containing the nostrils and used for breathing and smelling

mouth

o It is one of the opening the air comes into it is also an area where a certainamount of dust and impurities are intercepted and detected

pharynx

o section of alimentary canal that connects the mouth and nasal cavity to thelarynx and esophagus

trachea

o flexible tube commonly called the windpipeo semicircular rings of cartilage prevent trachea from collapsingo trachea eventually branches into two smaller passageways called bronchi

(singular bronchus)

bronchi

o One bronchus enters each lungo In the lung, each bronchus divides many

times to produce a network of

bronchioles

o Like the upper respiratory tract, thebronchi and bronchioles are lined with a

ciliated mucous membrane

bronchioles

what is the difference between bronchi and bronchioles?

alveoli

o At the end of each bronchiole is a grape-like cluster of tiny sacs called alveoli

o Alveoli are the site of gas exchange


38/58

lung

o Characteristic of air-breathing vertebrateso A lung is an internal respiratory surface connected to air by means of internal

passageways

o All lung systems contain 3 basic elements one or two lungs that have a moistrespiratory surface

a way of forcibly bringing air in contact with the lung surface a circulatory system to carry gases between the lungs and body cells

Describe the features of alveoli that adapt them to gas exchange.

Even though alveoli are so small there are huge numbers of them which results in a large surface area

for gas exchange. Also the wall of the alveoli is made up of a single layer of thin cells and so are the

capillaries, this creates a short diffusion distance for the gases. Therefore this allows rapid gas exchange.

The alveoli are covered by a dense network of blood capillaries which have a low oxygen and high

carbon dioxide concentrations. This allows oxygen to diffuse into the blood and carbon dioxide to

diffuse out of the blood. Finally, there are cells in the alveolar walls which secrete a fluid that keeps the

inner surface of the alveoli moist, allowing gases to dissolve. This fluid also contains a natural detergent

that prevents the sides of the alveoli from sticking together.

Summary:

1. Great numbers increase the surface area for gas exchange.2. Wall made up of single layer of cells and so are the walls of the capillaries so diffusion distance is

small allowing rapid gas exchange.

3. Covered by a dense network of capillaries which have low oxygen and high carbon dioxideconcentrations. This allows oxygen to diffuse into the blood and carbon dioxide to diffuse out of

the blood.

4. Some cells in the walls secret fluid allowing gases to dissolve. Fluid also prevents the sides ofalveoli from sticking together.

Label a diagram of the ventilation system


39/58


40/58

UNIT 3: PHYSICS

Guiding question: How has the scientific and mathematical development of optical technologies been

co-factors in the furthering of human understanding?

Describe what light iso Light is electromagnetic radiation that is visible to the human eye.o A medium is any physical substance that acts as a carrier for the transmission of energy.

Light travels through the vacuum of outer space which means it does not require a medium

for transmission.

o Light energy is transferred through radiationo Light is an electromagnetic wave that does not require a medium for transmission and

travels at the speed of light.

Discuss the electromagnetic spectrum

o The electromagnetic spectrum is the classification of electromagnetic waves by energy.

Type of Electromagnetic Wave Use/Phenomena

Radio Waves AM/FM radio stations TV signals Cellphones Radar Astronomy (discovery of pulsars)

Microwaves Telecommunications Microwave ovens Astronomy (background radiation

associated with the big bang)

Infrared light Remote controls Lasers Heat detection Physical therapy

Visible light Human vision Theatre/concert lighting Rainbows


41/58

Ultraviolet Causes skin to tan/sunburn Increases risk of skin cancer Ultraviolet lasers

X-rays Medical imaging Cancer treatments Security equipment (scanning luggage)Gamma Rays Cancer treatment Product of some nuclear decay

Define the terminology of reflection and laws of reflection

Plane: flat mirror

Incident ray:the incoming ray that strikes a surface

Reflected ray: the ray that bounces off a reflective surface

Normal: the perpendicular line to a mirror surface

Perpendicular: at right angles

Angle of incidence: the angle between the incident ray and the normalAngle of reflection: the angle between the reflected ray and the normal

Law of reflection: when light reflects off a surface, the angle of incidence is equal to the angle of

reflection as measured from the normal.


42/58

Draw ray diagrams for plane, convex and concave mirrors.

Plane:

o Plane mirrors use only the laws of reflection to determine the SALT properties of an object

Concave and Convex:


43/58

Rules for Convex & Concave Mirrorsdiagrams

The image can be located by using any two of these following rules

Rules:

1. Incident rays travelling parallel to the principle axis, strike the mirror and are reflectedthrough the focus.

Convex mirror*

Concave mirror

2. Incident rays that go through the center of the curvature are reflected perfectly back onthemselves

Convex mirror Concave Mirror

*With convex mirror, as if it were to go

through the focus


44/58

3. Incident rays that go through the focus (convex mirror: as if it were going through) arereflected parallel to the principle axis

Convex Mirror Concave Mirror

4. A ray aimed at the vertex will follow the law of reflectionConvex Mirror Concave Mirror

Explain using S.A.L.T., all the properties of the images produced in plane,

concave and convex mirrors

Plane:

They all create images with the same SALT properties

o SThe image is the same size as the objecto A the image produced is uprighto Lthe image is on the opposite side of the mirror as the object, the same distance from the

mirror as the object

o Tthe image is a virtual imageConvex:

All convex mirrors create images with the same SALT properties

o Ssmallero A uprighto Lon opposite side as object, before Co Tvirtual image


45/58

Concave:

Concave mirrors produce different images depending on where the object is located

Discuss refraction by referencing that light travels at different speed in different

media(substances)

Refraction is the bending of light as it travels from one medium (one refractive index) into another

medium (a material with a different refractive index)

o The angle of incidence is still defined as the angle between the normal and the incident rayo The refracted ray is the ray that is bent upon entering a second mediumo The angle of refraction is the angle between the normal and a refracted ray

*Going from a slow (more dense) to a fast (less dense) medium results in the ray being bentAWAYfrom

the normal

*Going from a fast (less dense) to a slow medium (more dense) results in the ray being bentTOWARDS

the normal


46/58

Define the index of refraction as the ratio of the speed of light in a substance

and the speed in vacuum.

o Ratio of the speed of light in a vacuum (or air) to the speed of light in a given medium.n=c/v

on is the index of refraction

o c is the speed of light in a vacuum (3.00 x 10^8 m/s)o v is the speed of light in a medium

Perform calculations to find the speed of light in different media.

o Light travels through air into a second medium that has a speed of 2.29 x 10^8 m/s.Find the index of refraction and identify medium B.

o n=c/v= 3.00 x 10^8 m/s / 2.29 x 10^8 m/s

= 1.31

o medium B is ice

Explain that the index of refraction (n) can also be determined by using the

Snells Law equation. n1sin1= n2sin2You can also use the index of refraction of any known substance, sin1 & sin2, to determine the index of

refraction of any unknown substance.

*Going from a slow (more dense) to a fast (less dense) medium results in the ray being bentAWAYfrom

the normal

*Going from a fast (less dense) to a slow medium (more dense) results in the ray being bentTOWARDSthe normal

Perform calculations using the sine laws for incident

and refracted light rays

o The index of refraction for ice is 1.31.if the angle ofincidence is 50, what will the angle of refraction be in ice,

coming in from air?

o n1 (sin1) = n2 (sin2)sin1 = n2 (sin2) / n1= (1) sin50 / 1.31

R= 35.8


47/58

Explain and calculate the critical angle.

o Light bends away from the normal when it speeds up at the boundaryof two media (example: light travels from acrylic to air).

o In this situation, the angle of refraction is always larger than the angleof incidence

o In fact, the angle of refraction continues to increase as the angle ofincidence increases.

o Eventually the angle on incidence will create an angle of refraction of90.

o The critical angle is the angle of incidencethat produces a refracted angle of 90.

Calculating the CA:

n2 = index of refraction for medium 2 (refracted side)

n1 = index of refraction for medium (incident side)

This formula comes from Snells law to derive to the following

Example:

Calculate the Critical Angle using the information on the diagram below

Explain the conditions where total internal reflection happens.o If you increase the angle of incidence past the critical angle, the refracted ray will no longer

exit the medium

o Instead, it will reflect back into the mediumo In other words, the refracted ray disappears; only a reflected ray is visibleo This is called total internal reflection


48/58

Identify several real life examples caused by refraction and total internal

reflection.

Fiber Optics

o A technology that uses light (totally internally reflected) to transmit information along aglass cable.

o The light must not escape the cable, so the material must have a higher index of refractionwhich leads to a small critical angle of incidence.

o This is used intensively in the communications industry because it is able to carry muchmore signal and requires less power.

Periscopes and Binoculars

o Glass has a critical angle of about 4.41. Therefore, if a prism is created insuch a way that the angle of incidence is greater than 41.1, total internal

reflection will result and the resultant image is better than one reflected

off a mirrored surface.

Periscopes: use triangular prisms to change the direction of light by 90 twice.Binoculars: use two triangular prisms to change the path of light.

DiamondsDiamonds are a real life example of total internal reflection. The sparkling effect

that diamonds display is due to the cut of the diamond faces, which, combined with

the high index of refraction for diamonds (n = 2.42), results in the total internal


49/58

reflection of light. The high refractive index means that the diamonds have very small critical angle. So

a great deal of incident light undergoes total internal reflection inside the diamond before eventually

exiting through a top face of the gemstone. This causes the sparkling effect.

Understand that lenses work by the refraction of light through a curved surface,

resulting in light rays being converged or diverged in a regular pattern

Distinguish between converging (convex) and diverging (concave) lenses

Converging Lens:

A lens that is thickest in the middle and that causes incident

parallel light rays to converge through a single point after

refraction.

Diverging Lens

A lens that is thinnest in the middle and that causes incident

parallel light rays to spread apart after refraction.

Define all the relevant terminology for thin lens diagrams

Optical Centre (O): the point at the exact center of the lens

Principal Focus (F):The point on the principal axis of a lens, where light rays parallel to the principal axis

converge after refraction

Principal Axis: the line that joins the optical center to the principal focus

Secondary Principal Focus (F):the focus on the other side of the lens


50/58

Draw ray diagrams for both types of lenses to find the location, size, type and

orientation of the image

Rules for converging

1. A ray parallel to the Principal axis is refracted through the Focus (F)

2. a ray through the Secondary Principal Focus (F) is refracted parallel to the Principal Axis (PA

3. A ray through the optical centre (O) continues straight through the lens, without being refracted

Rules for diverging

1. A ray parallel to the Principal axis is refracted as though it had come from the Focus (F)

2. A ray that is aimed at the secondary principal focus (F) will refract parallel to the principal axis

3. A ray through the optical centre (O) continues straight through the lens, without being refracted

The Thin Lens Equation

dodistance from the object to the optical centre didistance from the image to the optical centre

o (+ for real, - for virtual) ffocal length of the lens; distance from the optical centre to the principal focus (F)

o (+ for converging, - for diverging)


51/58

The Magnification Equation

hoheight of the object hiheight of the image Mmagnification (+ for upright, - for inverted)

Define the basic anatomy of the eye and

functions of each part

Sclera: white of the eye

Cornea: the clear bulging

surface in front of the eye. It is the main refractivesurface of the eye.

Pupil: the opening at the centre of the iris. The

iris adjusts the size of the pupil and controls the

amount of light that can enter the eye

Lens: a clear part of the eye behind the iris that helps to focus light, or an image, on the retina

Vitreous Humor: a clear gel that fills the space between lens and retina

Retina: the light sensitive tissue lining at the back of the eye. The retina converts light into electrical

impulses that are sent to the brain through the optic nerve.

Iris: the coloured part of the eye that regulates amount of light entering the eye

Optic nerve: a bundle of more than 1million nerve fibers that carries visual messages from the retina tothe brain

Describe several applications of lenses including

The Camera

A converging lens produces an inverted, real image as long as the object is at a distance greater than F

(the secondary principle focus). A camera is a device that makes use of this fact.

o A camera takes light from large, distant objects and forms of smaller, real images on the filmo This means that the object must be located at more than twice the focal length of the lens. As

the object changes position, its image will change location

o The location of the real image, however will be somewhere between F and 2Fo You cannot move the film in a camera back and forth to create a sharp


52/58

o So to compensate for the fixed position of the film, you move the lens in and out (Focusing)

The Movie Projector

The movie project is the opposite of a camera. A projector takes a small object (the film) and projects a

large, inverted, real image on a screen. Because the image is larger than the object, the film must be

located F and 2F. Also, because the image is inverted, the film must be loaded in to the projector

upside down so that what you see on the movie screen is upright. An overhead projector works in a

similar way.

The Magnifying Glass

The simplest optical device is the magnifying glass. It is a simple converging lens in which the object is

located between F and the lens. No real image is produced at this object location. The refracted rays

spread apart or diverge. However, the human brain extends these rays backwards and produces an

enlarged, virtual image located on the same side of the lens as the object.


53/58

Discuss near and far sightedness

HyperopiaFarsightedness

o Can see faro Difficulty seeing close

Myopianear sightedness

o Can see nearo Difficulty seeing far

Describe how corrective lenses, contact lenses, or laser eye surgery can correct

vision defects.

Contac-t Lenses

o Placed directly on the cornea of the eye and serves the same purpose as glasseso Shaped precisely so it can be used for correcting near and far sightednesso Contacts allow the eye to focus light in the right spot of the retinathe spot that produces the

clearest image

Corrective Lenses

o Designed to help your eyes focus light properly onto the retinao They bend light rays (before entering the eye) to the degree required by the condition of the

person

o Different types of corrective lens include glasses, contacts and intraocular lensesLazy eye surgery

o Helps correct Amblyopia which is known as a lazy eye(s)o This is a problem in the way the brain intercepts visual images from one or both eyes which

makes it harder for people to do things like reading a sign from a distance or catching a ball

o Treatment for amblyopia can correct the way the brain processes visual images and ultimately,strengthen vision


54/58


55/58


56/58

Melting Glaciers, Ice Sheets and Sea Ice

Over the last few decades, the average size of glaciers all over the world have decreased due tothe rising global temperatures

Ice sheets that covered expanses of Greenland and Antarctica are melting Arctic sea ice is also disappearing

Rising sea level

Global sea levels have risen significantly over the past 120 years When glaciers and ice sheets on land melt, water runs in to the oceans, causing the sea level to

rise.

The melting of frozen water sources may explain why sea level rise is accelerating In addition, thermal expansion (water expanding slightly when it warms up) could also lead to

rising sea levels

Changes in severe weather

Certain types of severe weather events, such as heat waves and hurricanes are becoming moreintense

In 2003, Europe experienced one of the most intense heat waves, where thousands of peopledied. Hurricanes have also become stronger over the past 50 years, fuelled by warmer ocean

temperatures

Changes in precipitation

In the northern hemisphere, more precipitation is falling as rain and less as snow There are more heavy precipitation events such as rainstorms and snowstorms Countries in more southern hemispheres are becoming more arid Precipitation is one of the main factors used to identify the climate of a regionchanges in

precipitation point to changes in climate

Changing seasons

Seasons in Canada and other parts of the world are gradually changing The amount of snow that remains on the ground in winter is decreasing throughout the

northern hemisphere

The frequency of cold days has been decreasing worldwide Very cold days and frosty nights are coming later in the year and ending earlier in the spring As a result, many regions are experiencing longer growing seasons

Changes in ecosystems

Trees and shrubs and other plants across north America are flowering earlier in the spring andanimals are breeding earlier in the year


57/58

Animal and plant communities are slowly migrating toward the poles, this will also result inundesirable insects and plants also moving north in to newer regions

Describe what a feedback loop is

A feedback loop is when the cause creates an effect that impacts the original cause.

In a positive feedback loop, the effect increases the original cause. In a negative feedback loop the effect decreases the original cause

Identify and describe examples of positive and negative feedback loops

Positive feedback loop: water vapour

The more water vapour enters the atmosphere when the climate warms up, due to increasedevaporation from earths lakes and oceans.

This causes the climate to warm up even more because water vapour is a greenhouse gas andtraps infrared vapor emitted by earth

If more relatively low clouds form in the atmosphere, then they trap thermal energy nearEarths surface, creating a more complex positive feedback loop

Water temperaturesmore (low) cloudseven warmer temperatures

CONVERSELY If the climate cools down, less water vapour forms and climate cools further (still apositive feedback loop)

Negative feedback loop: high altitude clouds

As temperatures increase this can cause clouds to form at high altitudes High clouds reflect the suns radiation back out to space which cools the temperature

Water temperaturesmore (high) cloudscooler temperatures

Negative feedback loop: birth

When woman are giving birth their muscles in the uterus contract This contraction of muscles causes the brain to send hormones to relieve pain in that area More contractions occur which results in more hormones being sent due to the pain The effect (or hormones being sent from the brain) are decreasing the original cause

(contraction of muscles/pain)


58/58

Explain the Albedo Effect

Albedo: the proportion of radiation reflected by a surface. Ice and snow have high albedos because

they reflect more radiation than grass or trees. The albedo effect is the relationship between ice and

earths temperature.

The albedo warming effectis the positive feedback loop in which

There is a rise in temperature Ice melts Which results in less of the suns radiation to be reflected by ice Leading to further increases in temperatures

Albedo cooling effectis also a positive feedback loop

Earths temperature decreases More ice is able to form Resulting in more of suns radiation reflected by the ice Leading to a further decrease in temperature

Explain how we can take actions to limit climate change

Grade 10 - Chemistry, Biology, Optics, Climate Change Study Guides.

Documents

Transcript of Grade 10 - Chemistry, Biology, Optics, Climate Change Study Guides.