The Chemistry of Life. The Nature of Matter Atoms All things are made of matter All things are made...

The Chemistry of Life

The Nature of MatterAtoms

All things are made of matter

Atom -basic unit of all matter Normally it is

electrically neutral (no charge)

Parts of the atomProtonsNeutronsElectrons

The Nature of Matter Protons

Protons + charged particle In the center of the

atom-nucleus Heavy

The Nature of Matter Neutrons

Neutrons Neutrally charged

particle In the nucleus Heavy

The Nature of Matter Electrons

Electrons - charged

particle In constant

motion in orbitals surrounding the nucleus

The Nature of MatterElements

Element-pure substance that consists of just one type of atom

114 in the periodic table – Only about 2 dozen commonly found in living things

Atoms have a 1 or 2 letter symbol

C = carbon N = nitrogen H = hydrogen O = oxygen, etc.

CCarbon12.011

Atomic Number= # of protons=#electrons

Atomic Mass= # of protons + # of neutrons

Where is Sodium?What is its atomic number?

Nonradioactive carbon-12 Nonradioactive carbon-13 Radioactive carbon-14

6 electrons6 protons6 neutrons

Isotopes of Carbon

• Isotopes--atoms of same element w/ a different # of

neutrons

The Nature of MatterIsotopes

The Nature of MatterRadioactive Isotopes

Isotope with unstable nucleus due to extra neutrons Break down at a constant

rate Give off dangerous

radiation Have uses too

C-14 dating- determines ages of rocks by analyzing isotopes found in them

Cancer treatment

The Nature of MatterCompounds

In nature, most elements are found combined with other elements in nature.

A chemical compound is a substance formed by the chemical combination of two or more elements in definite proportions.

The atoms in compounds are held together by chemical bonds.

The Nature of MatterBonding

Bonding -for some atoms to be stable they must gain, lose, or share electrons with another atom.

2 types of bonds-Ionic-Covalent

The Nature of MatterIonic Bonds

Ionic bonds - electrons transferred from one atom to another

Valence electrons- electrons in the last energy level of an atom

Formation of ions-negatively or positively charged atoms

The oppositely charged ions attract, forming the ionic bond

NaCl has ionic bonds

Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-)

Transferof electron

Protons +11Electrons -11Charge 0

Protons +17Electrons -17Charge 0

Protons +11Electrons -10Charge +1

Protons +17Electrons -18Charge -1

Ionic Bonding

The Nature of MatterCovalent Bonds

Covalent bonds --sharing electrons

Stronger than ionic Molecule--formed when

atoms are joined in a covalent bond

Properties of Water

Water covers ¾ of Earth’s surface

Most abundant molecule in living things

Universal solvent…dissolver of many substances found on Earth

Connects all parts of the world with others.

Properties of WaterPolar Molecule

Water has covalent bonds Water bonds are polar-

unequal sharing of electrons. Oxygen “pulls” harder on

negative electrons than H—gives O slight negative charge.

**Water has polar, covalent bonds

Properties of WaterHydrogen Bonds

Polarity causes water molecules to attract each other like magnets

H (+) attracts O (-) forming a hydrogen bond

Gives water special properties

Cohesion

Properties of WaterHydrogen Bonds

Hydrogen bonds are not as strong as covalent or ionic

Waters ability to form multiple hydrogen bonds is responsible for many of it’s special properties Cohesion – is an attraction between

molecules of the same substance Adhesion – is an attraction between

molecules of different substances

Properties of WaterSolutions

Solutions occur when one substance is dissolved in another.

Solute -gets dissolved Solvent -does the dissolving. Saltwater

What is the pH scale? The pH

scale measures how acidic or

basic a solution is.

The pH scale The pH scale is the

concentration of hydrogen ions in a given substance.

Identifying Acids and BasesAcids have a ph from 0-6 Lower pH value indicates a

stronger acid.

Bases have a pH from 8-14 Higher pH value indicates a

stronger base.

Definitions of Acids and Bases An acid is a substance that

breaks into ions in an aqueous solution.

A Base (alkaline) is a substance that breaks into ions in an aqueous solution.

Note: aqueous solution is any solution where is the solvent.

Did we Miss something??

What happens when the pH of a substance is 7?

Ans: A pH level of 7 indicates a Neutral Substance i.e: Water!

Test Your Knowledge

What is the range of an ACID on the pH scale?

Ans: 0-6

What is the range of a BASE and what is another name for a BASE?

Ans: 8-14, Alkaline

Characteristics Of Acids

Acids can be characterized by:

1. A sour taste.

2. It turns blue litmus paper red

3. It tastes sour. Try drinking lemon juice (citric acid)

Characteristics of Bases

A Base is characterized by:

1. A bitter taste. (Milk of Magnesia)

2. It feels slippery. (Soapy Water)

3. It turns Red Litmus Blue.

Why Learn about Acids & Bases?

What do you think is the pH level of miami dade county tap water?

The pH of a swimming pool must be checked periodically. Why?

Is it important for Lakes & Rivers to maintain a certain pH?

Today’s Experiment

Test the pH of Pepsi, tap water, and drain cleaner

GOOD LUCK!!!

Properties of WaterBuffers

Human homeostasis-human blood must be b/t pH 6.7-7.5

Body uses buffers, which are weak acids or bases, to neutralize sharp changes in blood pH

Macromolecules

copyright cmassengale

Organic Compounds

Compounds that contain CARBON are called organic.

Macromolecules are large organic molecules.

Carbon (C) Carbon has 4 electrons in

outer shell.

Carbon can form covalent bonds with as many as 4 other atoms (elements).

Usually with C, H, O or N.

Example: CH4(methane)

Macromolecules

Large organic molecules. Also called POLYMERS. Made up of smaller “building

blocks” called MONOMERS. Examples:

1. Carbohydrates2. Lipids3. Proteins4. Nucleic acids (DNA and

RNA)copyright cmassengale

Question:How Are

Macromolecules Formed?

Answer: Dehydration Synthesis

Also called “condensation reaction”

Forms polymers by combining monomers by “removing water”.

HO HO HH

http://nhscience.lonestar.edu/biol/dehydrat/dehydrat.html

Question: How are

Macromolecules separated or

digested?

Answer: Hydrolysis

Separates monomers by “adding water”

HO HO HH

Carbohydrates

Small sugar molecules to large sugar molecules.

Examples:A. monosaccharideB. disaccharideC. polysaccharide

CarbohydratesMonosaccharide: one sugar

Examples: glucose (C6H12O6)

deoxyriboseriboseFructoseGalactose

glucose

CarbohydratesDisaccharide: two sugar

unitExamples:

Sucrose (glucose+fructose)

Lactose (glucose+galactose)

Maltose (glucose+glucose)glucoseglucose

CarbohydratesPolysaccharide: many sugar

unitsExamples: starch (bread,

potatoes)glycogen (beef

muscle)cellulose

(lettuce, corn)

glucoseglucose

cellulose

Lipids

Lipids General term for compounds

which are not soluble in water. Lipids are soluble in hydrophobic

solvents. Remember: “stores the most

energy” Examples: 1. Fats

2. Phospholipids3. Oils4. Waxes5. Steroid hormones6. Triglycerides

LipidsSix functions of lipids:

1. Long term energy storage2. Protection against heat loss (insulation)3. Protection against physical shock4. Protection against water loss5. Chemical messengers (hormones)6. Major component of membranes (phospholipids)

LipidsTriglycerides:

composed of 1 glycerol and 3 fatty acids.

H-C----O

glycerol

C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3

fatty acids

C-CH2-CH2-CH2-CH =CH-CH2 -CH

2 -CH2 -CH

2 -CH3

=copyright cmassengale

Fatty AcidsThere are two kinds of fatty acids you may

see these on food labels:

1. Saturated fatty acids: no double bonds (bad)

2. Unsaturated fatty acids: double bonds (good)

saturated

C-CH2-CH2-CH2-CH=CH-CH2 -CH

2-CH2 -CH

2 -CH3

unsaturated

Proteins

Proteins (Polypeptides)

Amino acids (20 different kinds of aa) bonded together by peptide bonds (polypeptides).

Six functions of proteins:1. Storage: albumin (egg white)2. Transport: hemoglobin3. Regulatory: hormones4. Movement: muscles5. Structural: membranes, hair, nails6. Enzymes: cellular reactions

Proteins (Polypeptides)

Four levels of protein structure:A. Primary StructureB. Secondary Structure C. Tertiary Structure D. Quaternary Structure

Primary StructureAmino acids bonded

together by peptide bonds (straight chains)

aa1 aa2 aa3 aa4 aa5 aa6

Peptide Bonds

Amino Acids (aa)

Secondary Structure 3-dimensional folding

arrangement of a primary structure into coils and pleats held together by hydrogen bonds.

Two examples:

Alpha Helix

Beta Pleated Sheet

Hydrogen Bonds

Tertiary Structure Secondary structures bent and

folded into a more complex 3-D arrangement of linked polypeptides

Bonds: H-bonds, ionic, disulfide bridges (S-S)

Call a “subunit”.

Alpha Helix

Beta Pleated Sheet

Quaternary Structure

Composed of 2 or more “subunits”

Globular in shape Form in Aqueous

environments Example: enzymes

(hemoglobin)subunits

Nucleic Acids

Nucleic acids Two types:

a. Deoxyribonucleic acid (DNA- double helix) b. Ribonucleic acid (RNA-single strand)

Nucleic acids are composed of long chains of nucleotides linked by dehydration synthesis.

Nucleic acids Nucleotides include:

phosphate grouppentose sugar (5-carbon)nitrogenous bases:

adenine (A)thymine (T) DNA

onlyuracil (U) RNA onlycytosine (C)guanine (G)

Nucleotide

OO=P-O O

Phosphate Group

NNitrogenous base (A, G, C, or T)

Sugar(deoxyribose)

DNA - double helix

Organic MacromoleculesCarbohydrates

Structure: subunit = sugars Carbs are either

Sugars = monosaccharides sucrose, glucose, fructose short chains OR

Starches = polysaccharides sugars hooked together pasta, cellulose (plant cell walls) long chains

MONOSACCHARIDESPOLYSACCHARIDE

Organic MacromoleculesCarbohydrates

Function Main source of energy for living things Converted to ATP—gasoline for cells Monosaccharides = immediate E Polysaccharides = longer term E Plants store carbs as cellulose—gives

their cells strength

Organic Macromolecules Lipids

Structure: subunit = fatty acids and glycerol C and H Fats, oils, waxes are lipids Saturated and Unsaturated

fats Hydrophobic—”water-fearing”-

not dissolvable in water

FATTY ACIDS AND GLYCEROL

Organic Macromolecules Lipids

Function Store energy for use later Why should I care? Hormones Cell membranes Waterproof covering (skin)

Organic MacromoleculesNucleic Acids

Structure: subunit = nucleotides Nucleotides:

5 C sugar Phosphate group Nitrogenous base

DNA and RNA

NUCLEOTIDES NUCLEIC ACID

Organic MacromoleculesNucleic Acids

Function:Store and transmit hereditary (genetic) info

Organic MacromoleculesProteins

Structure: subunit = amino acids C, N, O, and H 20 different amino acids

form 1000’s of different proteins

AMINO ACIDS PROTEINS

Organic MacromoleculesProteins

Function Enzymes-proteins that control chemical

reactions Form bones and muscles Forms hair and nails (keratin) Part of cell membrane Steak, eggs, nuts, cheese PROTEINS ARE NOT SOURCES OF

ENERGY!

ORGANIC MACROMOLECULES

C-C BONDS

LIPIDS NUCLEIC ACIDS CARBOHYDRATES PROTEINS

Subunit:Glycerol and fatty acidsFats, oilsWaxesHydrophobic

Both for energyCellulose-cell Walls in plants

Subunit: Simple sugars(monosaccharides)Polysaccharides are starches likepasta and potatoes1C: 2H: 1O

Store and carrygeneticinformation

Subunit:NucleotidesDNA and RNA

Cell MembraneHormonesEnergy storage

Subunit:Amino acidsSteak, eggspeanuts

Help buildmuscle, hairand nailsAct as enzymesCell membrane

Chemical Reactions and Enzymes

Chemical Reactions Everything occurring in an

organism based on chemical reactions- process that changes one set of chemicals into another set

Slow (rusting) or fast (burning)

Breaking and remaking of bonds

Reactants-products

Chemical ReactionsReactant(s)

carbon + oxygen

C + O2CO2 + energy

carbon dioxide + energy

+ energy

Product(s)

black solid colorless gas colorless gas

Energy in Chemical Reactions Reactions involve changes in energy Some reactions release energy and

some have to absorb it ATP- form of energy absorbed or

released when bonds are made or broken

We get our ATP and organic macromolecules for body processes from food.

Plants get it through?

Some reactions are too slow or need lots of activation energy (ATP) to occur.

Enzymes are proteins that decrease the activation energy needed for these types of reactions to occur. They lower the energy “hill” making these

reactions easier and faster Digestion, nervous system signals, etc. all

require enzymes.Activation energy

Reactants

Products

Chemical Reactions and EnzymesEnzymes Enzyme activity regulated by many

variables pH Temperature Enzyme concentration

REACTANTS

PRODUCTS

The Chemistry of Life. The Nature of Matter Atoms All things are made of matter All things are made...

Documents

Transcript of The Chemistry of Life. The Nature of Matter Atoms All things are made of matter All things are made...

Whats a Matter?. What is Matter? Matter: Anything that takes up space and has mass Atom: Basic unit of matter Chemistry: The study of matter and all the.

Properties of Matter Atom-Periodic Table

The atom is the basic unit of matter. Ultimately all classes of matter can be identified or classified based on the type or types of atom that it contains.

Matter Classification. Microscopic Scale Atom – building block of all matter Molecule – two or more atoms chemically bonded together.

Complex Molecules (Macromolecules) 2012. What is an atom? smallestParticle of an element building blocksof all matter.

ELECTRICITY AND CIRCUITS. ATOM WHAT ALL MATTER IS MADE OF.

MATTER Mr. Atom.

Matter & The Atom

The ATOM. A History of the Atom as brief as possible Democritus – matter can be divided – coined ‘atom’ Aristotle – matter is continuous Jump to 1700’s.

Atom Vocabulary. Atom The smallest particle of an element the building blocks of all matter.

Chemical Bonds Atom – the smallest unit of matter indivisible Helium atom.

Atom The “smallest piece” of matter that still keeps all the properties of the element (we will talk about properties later) All matter is composed of.

Structure of Matter Structure of Matter Structure of Matter History of the Atom.

Atom – the smallest unit of matter Helium atom.

I. What is an atom? Atoms are the basic unit of matter All matter is made up of tiny atoms.

Chemistry 101. Elements are completely pure. All Matter is made up of Elements They are only made of one type of ATOM HELIUM ATOM.

Mileposts on the road to the atom All matter is made from elements All matter is made from elements What makes elements unique? What makes elements unique?

Chemistry What is an atom? An atom is the smallest unit of an element, that has all the chemical and physical characteristics of the element. All matter.

Classifying Matter. Quick Review Those itty bitty particles of matter? Do you remember their name? The basic building block of all matter? ATOM.

Atoms Chapter 4. Section 1: “The Development of the Atomic Theory” The atom is the smallest unit of all matter. The atom is the smallest unit of all matter.