bio 1 exam 1

polymer

built by linking monomers

carbohydrates, lipids, proteins, nucleic acids

4 Organic Molecules

Functional groups

small, reactive groups of atoms, which give larger molecules specific chemical properties

hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, phosphate,

functional groups that enter most frequently into biological reactions

functional groups

linked by covalent bonds to other atoms in biological molecules

functional groups

represented by the collective symbol R

hydroxyl

Polar. Hydrogen bonds with water to help dissolve molecules. Enables linkage to other molecules by condensation.

carbonyl

molecules with this func. grp. are major building blocks of carbohydrates and participate in the reactions supplying energy for cellular activities

aldehydes

carbonyl group is at the end of the carbon skeleton

ketone

carbonyl group within carbon skeleton

carboxyl

functional grp that gives organic molecules acidic properties

amino

functl grp that acts as an organic base by accepting a proton

phosphate

molecules that contain this functl grp reacts as a weak acids

sulfhydryl

easily converted into a covalent linkage

isomers

molecules with the same molecular formula but different structures

structural isomers

same chemical formula but arrangement of atoms are different

glucose (aldehyde) and fructose (ketone)

example of structural isomers

glucose

carbonyl at the end

fructose

carbonyl at the middle

stereoisomers

differ in how groups attached, left and right

enantiomers

mirror image molecules, chiral carbon

glucose and galactose

examples of stereoisomers

galactose

monomer

small, similar, chemical subunits

dehydration synthesis

formation of large molecules by the removal of water, monomers are joined to form polymers

hydrolysis

breakdown of large molecules by the addition of water, polymers are broken down to monomers

Carbohydrates

1:2:1 ratio of C,H,O

(CH2O)n

Monosaccharide

contain 3 to 7 carbon atoms

Disaccharide

two monosaccharides polymerize to form

polysaccharides

carbohydrate polymers with more than 10 linked monosaccharide monomers

cellulose

polysaccharide

polysaccharides

structural carbohydrates and energy storage molecules are this type of carbohydrates

Monosaccharides

simplest carbohydrate

Monosaccharides

6 carbon sugars play important roles

C6H12O6

chemical formula for glucose

linear

all monosaccharides occur in this form

glucose, fructose, galactose

example of monosaccharides, hexoses

five or more

monosaccharides with \________ carbons can fold back on themselves to assume a ring form, ex glucose

alpha glucose

enantiomer of glucose

-OH group pointing below the plane of the ring

beta glucose

enantiomer of glucose

-OH group pointing above the plane of the ring

Disaccharide

assembled from two monosaccharides joined by dehydration synthesis

maltose

ex of disaccharide

maltose

formed by a glycosidic bond linking two alpha glucose

alpha (1-4) linkage

sucrose

glucose + fructose

alpha (1-2) linkage

lactose

glucose + galactose

beta (1-4) linkage

Polysaccharides

long chains of monosaccharides

Polysaccharides

may be linear, unbranched, or one or more branches

glycogen

polysaccharide that animals use to store energy in (energy storage)

cellulose

polysaccharide plants use for structural support

chitin

polysaccharide arthropods and fungi use for structural support

modified glucose containing nitrogen-containing groups

amylose

polysaccharide joined by alpha (1-4) linkage, linear

glycogen

polysaccharide joined by alpha (1-4) linkage, linear

and alpha (1-6) linkage, branch

cellulose

glucose units joined by beta (1-4) linkages

cellulose microfibril

cellulose are packed into,

provides rigidity to cell wall

chitin

a reinforcing fiber in the external skeleton of arthropods and the cell walls of some fungi

lipids

water-insoluble, primarily nonpolar biological molecules composed mostly of hydrocarbons

Neutral lipids, phospholipids, steroids

three types of lipids

neutral lipids

energy source

energy storing molecules, no charged groups (nonpolar)

oils, fats

types of neutral lipids

oils

lipids that are liquid at room temperature

fats

lipids that are semisolid at room temperature

fatty acid

contains a single hydrocarbon chain with a carboxyl group at one end

triglycerides

formed by dehydration synthesis between three-carbon glycerol and 3 fatty acid side chains

ester linkage

Covalent bond between glycerol and fatty acid

triglycerides

serves as energy reserves in animals

store more than twice the calories per gram as carbohydrates

Triglycerides

layer of fatty tissue just under the skin that acts as insulation in mammals and birds

triglycerides

help make bird feathers waterproof

14 to 22

most common fatty acids have \_______ carbons

increases

as chain length \_____, fatty acids become less water soluble and more oily

saturated fatty acid

binds the maximum number of hydrogen atoms, only single bonds

saturated fatty acid

found in solid animal fats such as butter

less healthy

unsaturated fatty acid

bend at double bond, healthier

ex: vegetable oils

monounsaturated and polyunsaturated

types of unsaturated fats

monounsaturated

fatty acids with one double bond

polyunsaturated

fatty acids with more than one double bond and are more fluid at biological temps

stearic acid

saturated fats

oleic acid

unsaturated fatty acid, one double bond \= one kink

saturated

fatty acids that are stackable, stable, and solid

unsaturated

fats that are not stackable, compact and are liquid at room temp

trans fat

unsaturated fats, high LDL, formed by hydrogeneration

phospholipids

composed of head group, 2 fatty acids and a phosphate group

fatty acids

nonpolar tails of phospholipids

phosphate group

polar heads of phospholipids

phospholipid

if 3rd C in glycerol is attached to phosphate group

triglyceride

if 3rd C in glycerol is attached to fatty acid

phospholipids

form all biological membranes

phospholipids

structural plan of a \______