Cells and Cell Systems · Web viewScience 8: Biology Notes 15 Introduction to CellsName: _____...

Science 8: Biology Notes

Introduction to Cells Name: ___________________

Cells and Cell Systems

Characteristics of Living Things: Are composed of _________ Cells reproduce by ____________ into two

o This allows organisms to ________ and ___________ themselves Require ____________ Respond to their ________________ Have a life ___________ Produce __________

In order to be considered an organism … It must show ________ the characteristics of living things.

The Cell Theory States that: The __________ is the basic building block of all organisms All living organisms are composed of ________ or more ________ All cells come from _____________ cells

Cells can be sorted by … Their ___________ –skin, muscle, nerve … As _________, ___________, or ___________

o Plant and animal cells are _________ cellso Bacteria cells are not __________ cells

We call “true” cells ___________________ cells and not “true” cells prokaryotic cells.

What Makes Cells Different? To answer this we need to introduce a new term: ___________ Cells contain many different ____________ _____________ are specialized to carry out one function. Think of them as mini

___________ .

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True Animal and Plant Cells have many organelles in commonPresent in All Cells:

1. ________ membrane2. ______________3. ______________4. _____________ ER5. _____________ ER6. ________ apparatus7. _____________8. _____________9. _____________

Present in Some Cells:1. _____________2. _____________

True Plant Cells also have unique organelles:

1. Cell ___________2. ______________3. ______________ – tiny or absent

in most animal cells

Is That All That’s Known? There are many more ______________ in cells that we won’t be discussing There will probably be many more ______________ discovered as microscopy

techniques improve

Our Microscopes: Are monocular ( _______ eyepiece) Compound ( ______ lenses) Light reflected from its __________ (passes through specimen) Magnify specimens either _______ times or _______ times.

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A Closer Look at Cell Organelles as Seen by a a Light Microscope

The Nucleus Is the _________ centre for a cell It contains a cell’s ____________ which is its DNA (genetic information) Most human cells have _______ strands ( ____ from “mom” and _____ from

“dad”)

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DNA Is a special code that contains the

________ for the construction of most chemicals. These chemical make you – you!

This code is not allowed to leave the __________; it must be copied – just like a reference book cannot leave a ___________

The Cell Membrane Is the cell’s _________________. It selectively chooses

what is allowed to enter and exit. It cannot control the flow of ________ or __________.

These molecules are too small.

The Cytoplasm Is a __________ matrix that contains cell organelles. Within the cytoplasm is a scaffolding called the

_______________. The cytoplasm allows for rapid _________ of

nutrients and wastes.The Vacuole

Is a storage room for the holding of ____________ or _________. In __________ cells the vacuole occupies most of the cell. It is used to store

_____________ and to provide ____________.

The Flagellum Is a whip-like _________ that can help cells to ___________.

Cilia Are tiny ________ that work together to move a ________ or to

move _________ surrounding a cell.

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The Cell Wall Is found in _________ cells It is __________ permeable It provides ___________ for both the plant cell and the plant ___________ plants have an additional cell wall that supplies

even more support.

The Chloroplast Is a sugar assembly __________ found in green plant

cells. Carbon dioxide plus __________, in the presence of

light, react to produce ____________ and oxygen (a ___________!)

In symbols photosynthesis looks like:6 CO2 + 6 H2O + energy 1 C6H12O6 + 6 O2

A Closer Look at Cell Organelles as Seen by a Scanning Electron and Transmission Electron Microscope

Why Electrons? There is a limit to the ____________ available from light microscopes.

o Light waves are just too __________ to see spaces between tiny organelles.

Electrons … Are ____________ and are able to pass through tiny spaces – the spaces too

_________ for light to pass through If we fire a beam of electrons at a ________ sliced sample and then record

digitally where they penetrated and struck a recording plate then ,… We have a ______________ electron microscope!

TEMs allow us to build a … ______ - dimensional picture

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And … If we fire a beam of electrons at a thinly sliced sample and then record

digitally where they ___________ ___________ and struck a recording plate then …

We have a ____________ electron microscope!

SEMs allow us to build a … ________- dimensional picture of an object’s surface.

Using Observations from both a SEM and a TEM … allow graphic artists to buid three-dimensional ___________ of cells and

organelles. Biochemistry is used to determine what each organelle does ____________ for

the cell

Cell Organelles “Seen” by Electron MicroscopesMitochondria

The chemical reactions that occur inside mitochondria are part of respiration (cellular ____________ ).

All living ___________ and __________ cells must respire.

Convert the energy stored in __________ into “chemical __________” used to drive (pay for) many cell reactions.

This cell money is called ________ . Respiration involves the conversion of glucose, with the assistance of

_________, into carbon dioxide, __________, and ATP. In symbols respiration looks like:

1 C6H12O6 + 6 O2 6 CO2 + 6 H2O + 38 ATP

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Ribosomes Appear as dots in an electron micrograph. They are found ___________ to

the nuclear membrane and to the __________ ER. They are also found floating ________ in the cytoplasm. Ribosomes use the ________ of DNA to build proteins.

Rough Endoplasmic Reticulum When proteins are assembled

for cellular __________ to be used by another cell, they are built on the rough ER.

These proteins include many hormones, as well as digestive ____________.

Smooth Endoplasmic Reticulum Build special types of fats (called ________). These include ________

hormones.

Golgi Apparatus Takes generic proteins and lipids

made by the ER and tweaks their sugar _______.

These chemicals are then wrapped in a membrane and targeted for cellular _________.

Lysosomes Are ____________ plants and __________________ sites found in all animal

cells.

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Unicellular OrganismsAll unicellular organisms must:

Take in _________ , water and other ______________ Extract ____________ from food Eliminate __________ ______________

Types of Unicellular Organisms _____________ (prokaryotes) _____________ (eukaryotes) and some __________ (eukaryotes)

Bacteria Are different from plant and animal cells because:

o They have no ____________o They do not have ______________

They DO HAVE ribosomes!!!!Characteristics of Bacteria

Are all __________________ Are all __________________ Reproduce by ___________ fission (duplicating all of their “stuff” and then

splitting in two.)Not all Bacteria are Harmful

Many are _________________ Some are _________________

Bacterial ShapeBacteria come in three basic shapes:

_____________________ _____________________ _____________________

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Pathologists use characteristics like shape and clustering to help identify bacteria.

Antibiotics – Used to Fight Bacterial InfectionsWork by preventing:

• bacterial cell ____________ formation• bacterial cell ____________ function• ___________ synthesis• ___________ information synthesis

Or they interfere with other ___________ processes

Protists Most are __________________ Are _________________

o Have a _____________o Have _______________

Are ________-like, __________-like, or ___________-like Are found in __________ or __________ environments including ______________

and _______________

Plant-like Protists Have ________________ and can photosynthesize ________ Can also __________ smaller cells!!! Have a cell ______________ Produce much of our atmosphere’s ____________ Some are bioluminescent Can cause a red tide if the water is warm and full of nutrients

Animal-like Protists Move by one of the following

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o A false _________ (pseudopod)o _______________o _______________

Or do not move (these are usually ____________ )

Cells and Cell Systems

A Closer Look at Diffusion and Osmosis

Diffusion is the spreading out of _________ from an area of high _______________ to an area of low _________________.

Diffusion happens because particles are ______________.

Diffusion of water across a membrane is called ___________.

Osmosis attempts to ________________ concentration gradients of particles that cannot ___________ through a cell membrane.

As a cell gets ___________, diffusion takes longer.

There is a limit to cell size:The ________ of diffusion limits cell size. So a large organism needs _________ cells.Cells are organized into:

Ratio of Surface Area to Volume

Volume (length x width x height)

Surface Area (length x width x 6)

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_________: a grouping of cells that have similar shape and function

Cell organization continues:Different types of ___________ can be organized to form organs. ___________ have at least one ____________. Some organ examples include the: ___________, ___________, ___________, ___________, and __________.

Organization continues:___________ that have related functions can be grouped as ___________ systems. There is often overlap between the different ______________. __________ systems are combined to form an _______________.

Organ systems include the:

_____________ ____________ _____________ _____________ _____________

_____________ ____________ _____________ _____________ _____________

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Cell Wars: Defending Attacks from “Bad Boys”

Cell WarsViruses

o Some viruses cause ____________ infections; others are _____________.o Aside from ____________, there is no effective medical treatment for viral

infections.

Living Qualities of Viruses1. Have a protein _________ (capsid)2. Some have special ______________3. Have a small amount of __________ material

Non-living Qualities of Viruses1. Non-______________2. Do not __________3. Do not make or use ____________4. Do not _____________ to their environment5. Cannot reproduce on their ________________6. Can be _________________

So???:o Since viruses need to invade cells to _________________; they are not

considered ______________ organisms.

Virus ReproductionThere are two main kinds of virus reproduction:

1. destroy the host cell ___________________2. virus goes ________________ in host cell possibly for many years

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To Reproduce1. virus _________ its genetic material into a host cell2. genetic material takes over the cell’s __________________3. the cell makes virus ___________ 4. viruses assemble and the cell _____________ releasing the new viruses 5. newly released virus particles attack other _____________

How Our Bodies Fight Microscopic Invaders

Before the invader enters, we rely on:o Our __________ to act as a barriero Secretions like ____________, _____________, ____________ and – yuck! She

means ear wax!o The ___________ in our stomach

Once the invader is inside we rely on:o _________ Blood Cells to save us.o WBCs swallow the ____________ or ____________ damaged by invaders; or:o WBCs to produce _____________ that mark the invaders or damaged cells for

destruction by other WBCs

Antibodieso Are ____________ to the invadero They work similar to a lock and _______________o Each invader (lock) requires a different _____________ (key)

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DAN, YOU WILL NEED TO DO ADDITIONAL WORK ON THE IMMUNE SYSTEM. IMMUNOLOGY AND ENDOCRINOLOGY ARE THE TWO MOST COMPEX HUMAN BODY SYSTEMS. SO … KEEP IT SIMPLE.

Cellular Respiration Is the process by which your __________ use ______________ to release e energy

(ATP) from ______________ in the ________________ . In symbols respiration looks like:

1 C6H12O6 + 6 O2 6 CO2 + 6 H2O + 38 ATP As a result of cellular respiration, ________________________________, a waste, is

produced.

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Cells and Cell Systems · Web viewScience 8: Biology Notes 15 Introduction to CellsName: _____...

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