Biology Lecture Exam 2

monosaccharide

single or simple sugar

gram positive cell wall

thick cell wall

purple dye is hard to wash out of the cell

gram negative cell wall

thin peptidoglycan

purple dye is easily removed

Oligosaccharide

few monosaccharides bonded together via glycosidic bonds

polysaccharide

polymers of hexoses held together via glycosidic bonds; requires a dehydration reaction

Trioses

3-Carbon Sugar (C3H6O3)

glyceraldehyde and dihydroxyacetone

2 Important Trioses

Tetrose

4 Carbon Sugars (C4H8O4)

Pentose

5 Carbon Sugar (C5H10O5)

Hexose

6 Carbon Sugar (C6H12O6)

Chiral Carbon

a carbon atom bonded to 4 different atoms or groups of atoms

Steriosomers/Enantiomers

molecules that are non-superimposable mirror images of one another

Dextrorotary Isomers

Isomers that rotate light to the right

Levorotary Isomers

Isomers that rotates light to the left

D-Isomeric form

Which Isomeric form is used in biological systems

D-Ribose, D-Deoxyribose, D-Ribulose

3 Pentoses

photosynthesis

What is D-Ribulose used in?

D-galactose, D-glucose, D-fructose

3 Hexoses

Aldose

Carbonyl group is on the end

Ketose

Carbonyl group is in the middle

Anomer

an isomeric form of a monosaccharide that differs about their configuration at the chiral carbon formed during ring formation

Haworth Projection

corners in a ring formation representation of a molecule are carbons

Maltose

disaccharide of 2 a-D-glucose

Cellobiose

disaccharide of 2 B-D-glucose

Dehydration Reaction

during polymer formation water is lost

Hydrolysis Reaction

water is hydrolized during polymer breakdown (digestion)

Lactose

disaccharide of a-D-glucose and B-D-galactose

a-D-glucose

used to form ATP

Sucrose

disaccharide of a-D-glucose and B-D-fructose

cell identity

Biologically important purpose of Oligosaccharides

number of hexoses, type of hexose, type of glycosidic bond, branched, or unbranched

What distinguishes 1 polysaccharide from another

cellulose, starches, glycogens, chitin, peptidoglycan

5 types of polysaccharides

homopolymer

polymer that has a single type of monomer

Cellulose

most abundant organic molecule

cell wall of plants and some protists

B-D-glucose

8000 monomers/cellulose

linear

unbranches

insoluble but hydrophilic

homopolymer

100 cellulose —> 1 microfibril

100 microfibril —> cell wall

Starch

found in plant cells

a-D-glucose

helical

can be branched or unbranched

amylose and amylopectin

homopolymer

Amylose

1000 a-D-glucose

smaller

unbranched

slightly soluble

Amylopectin

100-6000 a-D-glucose

larger

branched

insoluble

glycogens

found in animals and some protists

intracellular location

storage form of hexoses (energy)

a-D-glucose

helical

highly branched

soluble

homopolymer

Osmosis

movement of water through a semi-permeable membrane down the concentration gradient

to reduce the osmotic pressure in the cell

Why store a-D-glucose as glycogen

Chitin

structural polysaccharide

extracellular location

forms exoskeleton of arthopods

cell wall of some fungi

insoluble

B-glycosidic bonds

linear

N-acetyle glucosamine

homopolymer

N-acetyl glucosamine

modified B-D-glucose

Peptidoglycan

cell wall of prokaryotes (bacteria)

linear

B-glycosidic bonds

heteropolymer

2 different modified B-D-glucoses (NAG, NAM)

has tetrapeptides

Tetrapeptide Bridge

4 amino acids linked together that come together to form crosslinks

simple lipids, compound lipids, steroids

3 types of lipids

fats, oils, and waxes

3 Examples of Simple Lipids

Compounds Lipids

simple lipids + additional functional group

peptidolipids, glycolipids, lipoproteins

3 types of compound lipids

steroids

physical properties are identical to simple and compound lipids but are structurally different.

non-polar and hydrophilic

unsaturated fatty acids, saturated fatty acids, cyclic fatty acids, trans fatty acids

4 main classes of fatty acids

palmitic acid and stearic acid

2 examples of saturated fatty acids

saturated fatty acid

carbons saturated with hydrogen

CH3(CH2)nCOOH

unsaturated fatty acid

double bonds in the carbon chain

oleic acid and palmitoleic acid

2 Examples of Unsaturated fatty acid

made up of unsaturated fatty acids that cannot be packed closely together

Why are oils liquid at room temperature?

made up of saturated fatty acids that can be packed closely together

why are fats solid at room temperature?

oils, polyunsaturated

Simple lipids in plants are:

fats, saturated

simple lipids in animals are:

Prostaglandins

“defense mechanism”

increase in inflammation, fever, and pain

Hydrogenation

high temperature + high pressure + H2 gas =

non-steroidal anti-inflammatory drugs

What does NSAIDs stand for

Trans fatty acids

hydrogens on a double bonded carbon are opposite

making it linear

hydrophobic, nonpolar, insoluble

Triglyceride

found primary in seeds

long term storage

simple lipids in plants

adipocytes

where is fat stored in animals?

protection and insulation

what is adipose tissue used for?

Waxes

ester of fatty acids and long-chain alcohol

phosphate group, functional group, glycerol, fatty acid

what are the 4 parts of a phospholipid

Choline

essential, CH3 nutrient

group with B-vitamins

Essential

either the body doesn’t produce it or doesn’t produce enough of it so it needs to be come from your diet

amphipathic

1 molecule has 2 different properties

micelle

phospholipid monolayer that forms with a nonpolar core but is soluble

liposome

phospholipid bi-layer where hydrophobic tails face each other and hydrophilic heads face the water

glycolipid

lipids that have a sugar attached to them

acetylcholine

responsible for muscle contractions

cholesterylester

fatty acid + OH group

storage form of cholesterol

Endosome

lipid vesicle formed as a result of endocytosis

Receptor-Mediated Endocytosis

Receptors on the surface of the cell bonds with a specific particle and only allows that one in

inhibits enzymes involved in synthesis, activates cholesterylester enzymes, inhibits LDL receptor production

What happens when there is an oversupply of cholesterol

Exogenous

comes from the outside of the cell

Exocytosis

removing something from a cell

Chylomicron

fat molecules mixed with cholesterol and coated with proteins

initially is 500-1200 nm but results in being 30-50 nm after losing triglycerides

LDL

bad cholesterol; increased risked of atherosclerosis

moves cholesterylesters

enters the cell via receptor-mediated endocytosis using Apo B-100 protein

polar, soluble

OH

polar or nonpolar

soluble or insoluble

polar, soluble

Carbonyl

polar or nonpolar

soluble or insoluble

Carboxyl

Weak acid

Amino Group

polar

can pick up a protein and become charged

weak base

buffer

weak acid + weak base =

Sufhydryl Group

nonpolar, insoluble

found in thiols

can form covalent bonds in protein

Phosphate Ion

Can turn a non-functional protein in to a functional one

phospholipids, ATP, GTP

Where can phosphate ions be found

Phosphotase

Can turn a now-functional protein into a non-functional protein

Methyl

saturated carbon

can change DNA structure

nonpolar

Protein

polymers of amino acids held together by peptide bonds

Amino Acid

25

how many amino acids are found naturally

21

How many amino acids are found in proteins

20

how many amino acids are found in DNA

Zwitterion

a molecule has both a positive and a negative charge

L-amino acids

which amino acids are found in protein