Chapter 3: Chemistry

I) Basic Chemistry

A. Atoms — basic building blocks of all Matter. The smallest part of an Element that still has all the properties of that element.           

Can not be subdivided by ordinary chemical means

B. Element- Made up of only one kind of atom

Example Iron or diamond only carbon atoms

Chapter 4— Chemistry of Life

1. Elements found in greatest percentage in living matter

Carbon C Hydrogen H2 Oxygen O2 and Nitrogen N2

2. Elements found in smaller quantities in living matter

Sulfur (S), Phosphorus (P), Magnesium (Mg2), Iodine (I2)

Iron (Fe), Calcium (Ca), Sodium (Na2), Chlorine (Cl2)

Potassium (K) Much less than C H O N


3. Inorganic Compounds       

Compounds which lack the element C or H (there are some exceptions)

a) Water ( you can survive days without food but not without water)

1. Most important inorganic compound. Makes up about 40% of cells. (70% of your body is water)

2 Acts as a universal solvent allows chemical reactions to take place.

b. Salts ex. NaCl, KC1,

1 Form mineral ions when they dissolve in water. Important in growth of bones and teeth, regulate enzyme system, and help maintain pH balance.

c. Inorganic acids and bases , Acid H Base OH Acid rain

1. Maintain proper pH levels in the body

2. Help maintain homeostasis

4. Organic Compounds - Compounds that contain both Carbon and Hydrogen . (the term organic is often used to mean many different things outside of Biology.)

a. Carbohydrates- Names end in ose

1. Made of C H O in a very specific ratio. Always twice as many H atoms as 0 atoms. Like water

2. Building block is a glucose (simple sugar)

3. Two Monosaccharides combined = A Disaccharide

4. Many Monosaccharides combine = a Polysaccharide


Monosaccharide = Glucose

Disaccharide — Fructose and Galactose

Polysaceharide —

a. Starch — Plant storage

b. Glycogen — Animal storage

c. Cellulose - Structural (plant cell wall)

d. Chitin — Structural (Insects exoskeleton)

b. Lipids - Fats, oils, waxes, cholesterol

1. Have C, H, O, but no definite proportions

2. Building blocks are .1 glycerol and 3 fatty acid molecules.

3. Used for long-term energy storage and to build cell membranes.

            (Fats give us twice the energy of carbs)

a. Two Types of Lipids

1. Unsaturated Fat- Corn and plant oils

• includes healthy fats essential for diets. Intake of these fats decrease the risk of heart attack.

• Liquid at room temperature. Because they are usually oils

2. Saturated Fats -Animal products

• unhealthy fats which have been linked to heart disease and heart attacks.

• solid at room temperature.

Cholesterol – in most tissue but can build up in blood vessles slowing flow and lead to myocardial infarction heart attacks and strokes.

c. Proteins-

1. Most abundant  organic compound in living things.

2. Building blocks are amino acids

3. Functions include:

a. Basic structure of membranes, chromosomes, and other cell parts.

b. Muscle cells are largely proteins.

c. Also found in blood plasma, cartilage, hair and nails.

4. 2 amino acids combined = a dipeptide   Many amino acids combined = a polypeptide

d. Nucleic Acids

1. Building blocks are: sugar, phosphate group, and a nitrogenous base.

2.Two types of Nucleic Acids

a. DNA stores and transmits genetic information.

b. RNA directs RNA + DNA synthesis

5.Chemica Formula vs. Structural formula

Chemical formula shows which elements are present and the amount of each atom present in the molecule. The elements are represented by chemical symbols and the ratios are represented by the subscripts.

C6h12o6, NH3, h2o, CO2

Structural Formula: not only shows the kind and amount of atoms by also shows in 2 dimensions how the atoms are bonded together.

Methane ch4

6. Dehydration Synthesis: a chemical reaction

“Dehydration”- Removal of water “Synthesis” — put together (or the process of building larger molecules from smaller ones)

* * Dehydration synthesis is how two monosaccharides are combined to form disaccharide.

7. Hydrolysis: another chemical reaction

Hydro – with water Lysis – to break apart

* * Hydrolysis is the oppositeof dehydration synthesis. It the process by which a disaccharide is broken down into two monosaccharides

Do Carbohydrate ID Lab

8. Chemical Reactions

Two types — Dehydration Synthesis and Hydrolysis

???- What controls that rate of these reactions?

a. Chemical Control by enzymes

1. Role of enzymes-

a. Control chemical reactions

b. Act as a Catalyst - chemical substance that can speed up the rate of a chemical reaction w/o itself being significantly changed or used up.

c. Each reaction requires a specific enzyme.

2. How enzymes work-

a. Substrate — Molecule that enzymes act upon in a chemical reaction.

b. Enzyme fit together with substrate to form an enzyme substrate couple

c. Enzymes are specific — only fit with 1 substrate.

1. Active site -  place on enzyme where reaction occurs.

d. When reaction is complete the enzyme and product separate.

e. Enzyme can then be re-used

1. rate of reaction is dependent on Temp, pH and or concentration

3. Structure of Enzymes-

a. They are large protein molecules

b. Often have a non-protein part called coenzyme.

c. Vitamins are usually coenzymes.

4. Enzyme names

a. Usually named for the substance they act on

b. End in “ase” examples:

Protease- breaks down proteins

Lipase breaks down lipids

Maltase breaks down maltose

Do enzyme graphing lab

 Acids, Bases, and the pH scale

1. Acid- Donates H+ (hydrogen) ions to a solution example: HC1 —> H+ arid Cl-

2. Base- Donates OH- ( Hydroxide ) ions to a solution example: NaOH —> Na+ and OH-

3. pH Scale- a scale used to determine how acidic or basic a solution may be.

pH = 0 strongly acidic , pH7 neutral pH = 14 strongly basic

Draw scale

Buffers- stabilize pH help it to stay constant,