HESI A2 Chemistry Biochem/Macromolecules

Carbohydrate

most abundant organic molecules made up of: CHO

sugars and starches

most important function is to store and provide energy for the body

carbohydrate functions

most important function is to store and provide energy for the body

monosaccharide

simple sugars (glucose and fructose)

monosaccharide structure

CHO ratio is 1:2:1

at least 3-7 carbon atoms in backbone

always have one carbonyl group (C=O) and at least 2 hydroxyl groups (-OH)

disaccharide

two monosaccharides joined together by a glycosidic bond (sucrose, lactose)

oligosaccharide

3-6 monosaccharides joined together

Polysaccharide

more than 6 monosaccharides joined together

(amylose, amylopectin, cellulose, glycogen)

Starch

storage form of glucose in plants

amylose and amylopectin, digestible by humans via enzyme amylase

Cellulose

carbohydrate component of plant cell walls structure

not digestible but is fiber in our diets

Glycogen

storage form of glucose in animals stored in liver and muscle tissue

dehydration synthesis

joining of two monosaccharides by removing water, glycosidic bond

hydrolysis reaction

cleaving (splitting) of the glycosidic bond that joins two monosaccharides by adding water

important for digestion of starch

glycolysis

an anaerobic chemical pathway occurring in the cytoplasm that breaks down one molecule of glucose into 2 pyruvate, 2 ATP and 2 NADH

pyruvate is converted into acetyl-coA and then enters the kreb cycle

krebs cycle (citric acid cycle)

an aerobic chemical pathway occurring in the mitochondria, starts with acetyl-coA and produces NADH, FADH2, 1 ATP & CO2 as a waste product

does not use oxygen directly

occurs twice per glucose

feeds NADH/FADH2 to the ETC

Electron transport chain and oxidative phosphorylation

aerobic chemical pathway occurring in the mitochondria

electron carriers NADH and FADH2 transfer electrons to oxygen (final electron acceptor) forming water as a waste product

proton gradient drives ATP synthase to produce ~28-34 ATP via chemiosmosis

main site of ATP production

anaerobic glycolysis

process of converting glucose to lactate instead of pyruvate, causes burning/cramping in the muscles during intense exercise

gluconeogenesis

The formation of glucose by the liver from noncarbohydrate sources, such as amino acids (proteins)

Glycogenolysis

breakdown of glycogen to glucose when in need of energy

proteins

composed of larger groups of amino acids

ex. albumin, smaller protein within blood

amino acids

molecule composed of a carbon atom bonded with 4 other groups: an amine group (NH2), a carboxyl group (COOH), a hydrogen, and a special R group.

building blocks of proteins

only 20 amino acids needed to make all proteins necessary for life in humans

dipeptide

two amino acids joined via peptide bond

polypeptide/peptide

group of fewer than 30 amino acids joined together

lipids

oils, fats, and fatty acids

hydrophobic (do not dissolve in water)

insulate body, maintain body temperature, healthy cell function

triglyceride

neutral fat

three fatty acids generally joined to a glycerol or other backbone structure

fatty acids

consists of a hydrocarbon chain with a carboxyl acid (COOH) group at end

phospholipids

two fatty acids and a phosphate group joined to a glycerol backbone

essential component of the phospholipid bilayer in the cell membrane

Cholesterol

four ring structure and side chain

very important precursor to steroid hormones and other biological molecules

saturated fats

No double bonds; solid at room temperature.

unsaturated fats

has double bonds; liquid at room temperature.

polyunsaturated fat

more than one double bond

nucleic acids

DNA and RNA

nucleotide chains that convey genetic information found in all living cells and viruses

mostly within the nucleus but sometimes found in the cytoplasm and mitochondria of individual cells

DNA

deoxyribose nucleic acid

five carbon sugar/pentose backbone, a phosphate, double-helix shape

DNA bases

adenine, cytosine, guanine, thymine (ACGT)

adenine-thymine

cytosine-guanine

antiparallel

the two sugar phosphate chains in DNA running in opposite directions (one up, one down)

RNA

ribose nucleic acid

single strand of ribose sugar and phosphate in a chain

RNA bases

Adenine, Uracil, Cytosine, Guanine

Adenine-Uracil

Cytosine-Guanine

phospholipid bilayer

double layer with hydrophilic heads facing outward towards the watery environment and the hydrophobic tails facing inward, creating a barrier that separates the cell from its surroundings

creates a selectively permeable cell membrane, help to maintain homeostasis