CCS BiologyMr. Bogusch

CHAPTER 2: THE CHEMISTRY OF LIFESECTION 3: CARBON COMPOUNDS

The Chemistry of Carbon

• Organic Chemistry – study of chemistry that contain bonds between carbon atoms

• Carbon can bond with many elements, including hydrogen, oxygen, phosphorus, sulfur, and nitrogen to form the molecules of life

The Chemistry of Carbon

•Characteristics of carbon• Carbon has 4 valence electrons – meaning it can make up to 4 covalent bonds with itself or many other elements

• Carbon can bond with itself in a single, double, or triple covalent bond

The Chemistry of Carbon

•Macromolecules• Macromolecules – “giant molecules” --molecules made from hundreds to thousands of smaller molecules

• Polymerization – process by which large compounds are formed by joining smaller ones together• Monomers – one molecule or “single part”

• Polymers – many molecules or “many parts”

Four Major Groups of Macromolecules (found in living things)

BiologicalMacromolec

ules

Carbohydrates

Lipids

Nucleic

Acids

Proteins

•Carbohydrates• Carbohydrates – compounds made up of carbon, hydrogen, and oxygen atoms usually in a ratio of 1:2:1

• Living things use carbohydrates as their main sources of energy. Plants, some animals, and other organisms also use carbohydrates for structural purposes.

• The breakdown of glucose provides immediately energy for cell activities

• Starches – extra sugar stored as complex carbohydrates

Four Major Groups of Macromolecules (found in living things)

Carbohydrates

•Simples Sugars• Monosaccharides – single sugar molecules

• For example: Glucose, fructose (found in fruit), galactose (found in milk)

• Disaccharide – two monosaccharides (single sugars) joined together• For example: Sucrose (disaccharide) if made by joining glucose and fructose.

Four Major Groups of Macromolecules (found in living things)

Carbohydrates

Simples Sugars

•Complex Carbohydrates• Polysaccharides – large molecules formed from joining monosaccharides

• Animal Carbohydrates• Glycogen - (animal starch) is formed by joining many glucose monosaccharides together• Glycogen supplies energy for muscle contraction

• Plant Carbohydrates• Starch – polysaccharide that plants use to store sugar

• Cellulose – fibrous polysaccharide plants use for strength and rigidity• Cellulose is the main component of wood and paper

Four Major Groups of Macromolecules (found in living things)

Carbohydrates

Four Major Groups of Macromolecules (found in living things) Carbohydr

atesCarbohydrates

Lipids

Four Major Groups of Macromolecules (found in living things)

Lipids• Lipids – nonpolar molecules that cannot dissolve in

water and made of mostly carbon and hydrogen atoms

• Lipids can be used to store energy. Some lipids are important parts of biological membranes and waterproof coverings.

• Steroids (which include hormones) are lipidsHormones - chemical messengers

Four Major Groups of Macromolecules (found in living things)

Lipids

Four Major Groups of Macromolecules (found in living things)

Lipids

• Lipids are made of a glycerol molecule and fatty acid tails• Saturated fatty acid – the fatty acid tail is

completely filled with hydrogen atoms• Fats that are solid at room temperature

• Butter, grease• Polyunsaturated fatty acid (unsaturated) – the

fatty acid tail has at least ne carbon – carbon double bond• Fats that are liquid at room temperature

• Olive oil, corn oil canola oil, peanut oil

Four Major Groups of Macromolecules (found in living things)

Lipids

Four Major Groups of Macromolecules (found in living things) Nucle

ic AcidsNucleic Acids

• Nucleic Acid – macromolecules that contain nucleotides

• Nucleotides – molecule that has a nitrogenous base, 5-carbon sugar, and a phosphate group.

• ATP – adenosine triphosphate – chemical energy in organisms

NucleotideATP

Four Major Groups of Macromolecules (found in living things) Nucle

ic Acids

• Hereditary information – DNA and RNA• Nucleic Acids store and

transmit hereditary, or genetic information• Ribonucleic Acid – RNA

- transfer the instructions to build proteins from the nucleus to ribosomes (where proteins are built)

• Deoxyribonucleic Acid – DNA - have the instructions to build proteins

Nucleic Acids - DNA

Four Major Groups of Macromolecules (found in living things) Nucle

ic Acids

Four Major Groups of Macromolecules (found in living things)

ProteinsProteins

• Protein – macromolecules that are made of chains (polymers) of amino acids• Proteins are assembled by RNA from the

instructions of DNA• Amino acids – compounds with an amino group

(NH2) on one end and a carboxyl group (COOH) on the other end.• Peptide bonds (covalent bonds) link amino

acids together.

Four Major Groups of Macromolecules (found in living things)

Proteins

• Some proteins control the rate of reactions and regulate cell processes. Other proteins from important cellular structures, while others transport substances into or out of cells to help fight disease.

Proteins DO EVERTHING!!!!

Four Major Groups of Macromolecules (found in living things) Protei

ns• Structure and Function

• There are around 20 different amino acids found in nature

• Amino acids are diverse macromolecules – some are acidic and some are basic, some are polar and some are nonpolar (meaning some will dissolve in water and some will not)

Four Major Groups of Macromolecules (found in living things)

Proteins

Four Major Groups of Macromolecules (found in living things)

Chapter 2: Science of BiologySection 4: Chemical Reactions and Enzymes

Chemical Reactions

• Chemical reaction – process that changes, or transforms, one set of chemicals into another• Mass and energy are conserved during the reaction• The law of conservation of energy states that energy may neither be created nor destroyed.

1. As it enters the blood, carbon dioxide (CO2) reacts with water to produce carbonic acid (H2CO3), which is highly soluble.

2. This chemical reaction enables the blood to carry carbon dioxide to the lungs.

3. In the lungs, the reaction is reversed and produces carbon dioxide gas, which you exhale.

Chemical Reactions• Reactants – elements or compounds that enter the

chemical reaction• Products – elements or compounds produced by

the chemical reaction• Chemical reactions involve changes in the

chemical bonds that joins atoms in compounds

Chemical Reaction Example

Energy in Reactions• Chemical reactions that release energy often

occur on their own, or spontaneously.• For example: burning of hydrogen gas

• 2H2 + O2 -- 2H2O

Hindenburg

Energy in Reactions• Chemical reactions that absorb energy will not

occur without a source of energy• Activation Energy – energy needed to start a

chemical reaction.

Enzymes• Catalyst – a substance that speeds up the rate of a

chemical reaction• Enzyme – Proteins that speed up chemical

reactions by reducing the activation energy (amount of energy needed to start the chemical reaction)• Enzymes are biological catalyst

Enzymes• The Enzyme- Substrate Complex

• Substrate – the substance an enzyme acts on• The reactants of enzyme-catalyzed reactions

• Active site – the site on the enzyme where that substrate binds onto.• Similar to a “lock and key”

ENZYMES

ENZYMES

ENZYMES• Control (regulation)

of Enzyme Activity• Temperature, pH,

and other molecules can affect the activity of enzymes• For example:

Human enzymes work best at a temperature of 37°C (98.6°F).• Human

enzymes in the stomach work best at a pH of 2