Biological Molecules

Lipids

Proteins

Carbohydrates

Nucleic Acid

there are 20 different amino acids commonly found in living things

Proteins can be made up of one or more polypeptides giving them a wide range of forms

Made up of amino acid chains- polymers of amino acids called polypeptides

disaccharide- two monomers connected by a dehydration reaction

simple sugars or complex sugars (polymers)

monosaccharide- one ring

Phospholipids

fused ring

Oils, Fats Waxes

Each nucleotide contains: 5-C sugar-either Ribose or deoxyribose (has one less oxygen), phosphate group, nitrogen-containing base- adenine (2-ring), guanine (2-ring), cytosine (1-ring) or thymine (1-ring)

In DNA: the phosphate group of one nucleotide is covalently bound to the sugar of another

Made up of long chains of nucleotides -contain N and P (in addition to C, H, O

C, H, O - 1:2:1 ration

contain hydroxyl group (functional group) making them polar

Short term energy storage

Quick energy from hydrolysis of monosaccharides

polysaccharides function as storage or structural molecules

Contain fatty acid subunits- long chains of C and H with a carboxyl group at one end

Fats and oils are triglycerides- 3 fatty acid subunits and 1 glyerol

Conatin C, H, and O

Most fats- animals- saturated (no double bonds with hydrocarbons)

Most oils- plant seeds- unsaturated (at least one double bond with hydrocarbons) *double bonds cause "kinks" keeping them liquid at room temperature

Hydrogenated oils (trans fats) created by breaking fatty acid double bonds- our bodies are unsure of how to "deal" with these molecules and the trans fats can lead to an increase in bad cholesterol

Waxes are not a food source- we don't have the enzymes to break them dow

One end is nonpolar because of fatty acid chains

Other end is polar because of phosphate - nitrogen group

Similar to oils, but have a phosphate group

Major component of cell membrane

Only 2 fatty acid chains- fats have 3

Cholesterol is a type of steroid

4 fused rings of carbon with different functional groups - steroids

Joined with ester bonds- glycerol molecule and 3 fatty acid molecules by dehydration synthesis

Peptide bond- connects the amino group of one amino acid and the carboxyl group of another

2-50 amino acids linked together: dipeptide

Four Levels to Organization

50+ amino acids: polypeptide or protein

Hydrogen bonds hold bases together

Functions:

DNA- Sequence of nucleotides is different in every species=unique code to synthesize proteins (made up of 2 nucleotide chains that twist to form a "double helix"

RNA- copies of DNA, carries genetic code from nucleus to cytoplasm so that it can be read/ proteins can be synthesized

Cyclic AMP- intracellular messengers that carry chemical signals

ATP transports energy within cells, product of cellular respiration

2) Secondary Structure- Formed by hydrogen bonds between the amino and carboxyl group of amino acids

3) Tertiary Structure- complex 3-D structure determined by cellular environment, disulfide bridges can contribute to structure, form when 2 cysteines bond together

1) primary structure- sequence of amino acids (determined by DNA) (peptide bond)

4) Quaternary structure -in some proteins individual polypeptide chains are linked together

(alpha) helix structure- caused by hydrogen bonds that form betwee Co of hydroxyl groups and hydrogen in NH groups of same peptide

(Beta) pleated sheet- repeated folds form when a peptide folds on itself and hydrogen bonds form

Structure and Function

Denaturation- occurs when the 2 and 3 structures of a protein have been altered, protein cant function properly

Determined by DNA- amino acids must be in proper sequence in order to be in the correct place in a protein

Proteins can be denatured by: changes in temp, changes in salinity, changes in pH