Biomolecules

• Any molecule produced by a living organism

• All biomolecules contain Carbon

Biomolecules

• Large molecules in living cells are known as biomolecules --- “giant molecules”

• biomolecules are made by joining smaller unites called MONOMERS together to for POLYMERS

The process of joining together monomers is known as POLYMERIZATION

4 groups of biomolecules

1.) carbohydrates

2.) lipids

3.) nucleic acids

4.) proteins

Carbohydrates• Made up of carbons, hydrogen and oxygen

atoms in a 1: 2: 1 ratio

• Uses:– Main source of energy– Structural purposes

• Monomers are known as MONOSACCHARIDES

- MONOSACCHARIDES join to form POLYSACCHARIDES

CARBOHYDRATES• Sugars (fruits, pasta, bread)

• Contain C, H, O in a 1:2:1 ratio

• Used for energy

• Types: MonosaccharideDisaccharidesPolysaccharides

• The monosaccharides for carbs are simple sugars– Ex: Glucose, galactose, fructose

Carbohydrates• Carbohydrates include:• Small sugar molecules

in soft drinks• Long starch molecules

in pasta and potatoes

Monosaccharides:

Called simple sugars

Include glucose, fructose, & galactoseHave the same chemical, but different structural formulas

C6H12O6

Monosaccharides

Glucose is found in sports drinks

Fructose is found in fruitsHoney contains both glucose & fructoseGalactose is called “milk sugar”

Disaccharides

A disaccharide is a double sugar

They’re made by joining two monosaccharides

Involves removing a water molecule (dehydration)

Disaccharides

Common disaccharides include:

Sucrose (table sugar)Lactose (Milk Sugar)Maltose (Grain sugar)

Sucrose is composed of glucose + fructose

Polysaccharides

Complex carbohydrates

Composed of many sugar monomers linked togetherPolymers of monosaccharide chains

Examples of Polysaccharides

Starch

Glycogen

Cellulose

Glucose Monomer

Lipids

• Made mostly from carbon and oxygen atoms– Ex. Fats, oils, waxes

• Uses:– Store Energy– Important factor in cell membranes– Chemical messengers

Function of Lipids

Fats store energy, help to insulate the body, and cushion and protect organs

Lipids contain two parts:

1.) glycerol heads

2.) fatty acid chain tails

Glycerol + fatty acid tail

• There are two types of lipids1.) Saturated contain only single bonds

Ex. Solid fat

2.) unsaturated contain double bonds

Ex. Liquid fat

Fats in Organisms

Most animal fats have a high proportion of saturated fatty acids & exist as solids at room temperature (butter, margarine, shortening)

Fats in Organisms

Most plant oils tend to be low in saturated fatty acids & exist as liquids at room temperature (oils)

Lipids

Lipids are hydrophobic –”water fearing”

Includes fats, waxes, steroids, & oils

Do NOT mix with water

FAT MOLECULE

Steroids

The carbon skeleton of steroids is bent to form 4 fused rings

Cholesterol is the “base steroid” from which your body produces other steroids

Estrogen & testosterone are also steroids

Cholesterol

TestosteroneEstrogen

Nucleic Acids

Store hereditary information

Contain information for making all the body’s proteinsTwo types exist --- DNA & RNA

Bases

Each DNA nucleotide has one of the following bases:

Thymine (T) Cytosine (C)

Adenine (A) Guanine (G)

–Adenine (A)

–Guanine (G)

–Thymine (T)

–Cytosine (C)

NUCLEIC ACIDS • DNA & RNA

• Made of nucleotides: sugar + a nitrogenous base + a phosphate group

• Contain C, H, O, N & P

• Contain genetic information

• Control the activities of cells

Proteins

Proteins are polymers made of monomers called amino acids

All proteins are made of 20 different amino acids linked in different orders

Proteins are used to build cells, act as hormones & enzymes, and do much of the work in a cell

ProteinMacromolecules that contain nitrogen, carbon,

hydrogen, and oxygen

Monomers are called amino acids

Amino acids have an amino group (-NH2) and a carboxyl group (-COOH)

Uses:Control the rate of reactions and

regulate cell processes.Form bones and musclesTransport substance into or out

of cellsHelp to fight disease

20 Amino Acid Monomers

Structure of Amino Acids

Amino acids have a central carbon with 4 things boded to it:Amino group -NH3Carboxyl group -

COOHHydrogen -H

Side group -R

Amino

group

Carboxylgroup

R group

Side groups

Leucine -hydrophobic

Serine-hydrophillic

Proteins as Enzymes

Many proteins act as biological catalysts or enzymes

Thousands of different enzymes exist in the body

Enzymes control the rate of chemical reactions by weakening bonds, thus lowering the amount of activation energy needed for the reaction

Primary Protein Structure

The primary structure is the specific sequence of amino acids in a protein

Amino Acid

Protein Structures

Hydrogen bond

Pleated sheet

Amino acid

(a) Primary structure

Hydrogen bond

Alpha helix

(b) Secondary structure

Polypeptide(single subunit)

(c) Tertiary structure

(d) Quaternary structure

Denaturating Proteins

Changes in temperature & pH can denature (unfold) a protein so it

no longer worksCooking denatures protein in eggs

Milk protein separates into curds & whey when it denatures

Changing Amino Acid Sequence

Substitution of one amino acid for another in hemoglobin causes

sickle-cell disease

(a) Normal red blood cell Normal hemoglobin

12 3

4 56

7. . . 146

(b) Sickled red blood cell Sickle-cell hemoglobin

2 314 5

67. . . 146