Ch 3- carbs + lipids, DNA Flashcards
Polysaccharides
longer polymers than disaccharides, joined through dehydration synthesis
Starches
insoluble polysaccharides. chain of alpha glucose subunits
Maltose
disaccharide, alpha 1,4 glyocosidic linkage
Lactose
beta glycosidic bonds, galactose + glucose
cellulose
chain of beta 1,4 glucose subunits- we cannot digest this, its dietary fiber, humans do not have the enzyme to break down beta 1,4 linkages. unbrached.
amylose
type of starch, unbranched, alpha 1,4 linkages. 20% of a potato.
amylopectin
\alpha 1,6 linkages. “branched”. 80% of a potato- we can digest this! its a type of starch
peptidoglycin
bacterial cell wall. beta 1,4 linkage with NH , CO side groups coming off it.
chitin
structural polysaccharide. responsible for insect’s/lobster shells. beta 1,4 linkage. with NH, CO side groups coming off it.
Lipids
group of molecules insoluble in water. fats, waxes, oils, etc
lipids in water do what?
form micelles
Triglycerides
fat molecules. 3 fatty acids. glycerol + 3 fatty acids = triglyceride.
terpene
type of lipid. found in biological pigments, such as chlorophyll
steroid
type of lipid. play important roles in membranes, basis of chemical signaling . composed of 4 carbon rings.
prostaglandins
type of lipid. 2 nonpolar tails + 5 carbon ring. modified fatty acid. causes smooth muscle contraction.
waxes
esters of long chain fatty acids and long chain alochol
saturated fat
solid at room temperature, as the single bonds between carbons allow molecule to remain tightly packed.every carbon bonded to 2+ Hydrogens.
unsaturated fat
liquid oil at room temp: double bonds between some carbons prevent triglyceride from closely aligning
polyunsaturated
fatty acids with more than one double bond
phospholipids
composed of: head- glycerol, phosphate, choline. tail: fatty acids. form the core of all biological membranes.
trans fats vs cis fat
trans: H located across from each other. cis: opposite from each other. since no kink in chain of trans fat, result in higher melting point, more weight gain
amphipathic molecules
both polar and non polar. ex: phospholipids
phospholipid bilayer
lipids lined up so that heads face out, tails face in: as seen in biological membranes
hydroxyl group
OH. polar, soluble in water. more OH groups = more soluble
Fatty acid structure
O
OH- C-C-C-…..
-this ionizes in aqueous conditions, and the H pops off
The C’s form a long nonpolar tails “hydrophobic” fears water.
And then the left part is the polar head. ‘hydrophilic.’
what is the structure of an ester?
O
R-C-O-R
its just an O with C’s on either end
How many carbons will you typically see in a fatty acid and what is the trend?
Fatty acid always has an even number of carbons. Reason is that its assembled from 2 carbon units. Numbers are usually like 12,14,16- not 60.
Glycerol structure
H-C-OH +
H-C-OH
H-C-OH
mono vs di vs triglyceride?
You could put 1,2 or 3 fatty acids onto a glycerol. Mono, di or tri glyceride.
what is choline and what does it look like?
charged group on top of a phospholipid.
draw the formation of a fat molecule
via dehydration synthesis: 3 fatty acids + 1 glycerol -> fat + 3 h20
structure of carbonyl group?
basic structure: o-C-R-R. 2 varieties: ketones, aldehydes.
structure of an aldehyde and example of one?
ex: glucose has an aldehyde group on the top
ketone structue and example of one?
O-C-R-R
ex:
amino group and properties?
H-N-H
R-NH3 is a proton acceptor, aka a base. SOLUBLE.
methyl group structure and solubility
non soluble. R-CH3.
ex: pyruvate.
carboxyl group structure and properties
COOH. acid form increases solubility- loses its H+ when it ionizes
phosphate group structure and properties
in acid form, it increases solubility.
glycogen
starch. long, branchy chain, alpha 1/4 linkage . looks identical to amylose/amylopectin. found in liver and muscles, excellent for energy stores (easy for amylase to hack off 2 glucoses at a time and use for energy)
amylase
digests starch by breaking off 2 sugars (aka 1 maltose) at a time from a long chain
maltose
alpha 1,4 linkage of 2 glucoses
is glucose typically in D or L form?
D
structural isomer and example
moving the actual backbone. ex: moving the carbonyl group glucose/fructose
stereoisomer- and which carbon is it on?
same structure, but one side group is flipped in a mirror image. ex; glucose/galactose. it’s carbon #4 that flips.
hexose
6 carbon sugar
source of energy from carbs is stored in which kind of bonds?
C-H bonds
T/F: carbs are typically soluble in water
true! bc of all those hydroxyl groups
suffix of ose is for who?
carbs/sugars
why does orientation not matter for the last carbon in glucose?
not chiral- has 2 H’s on it
Kinase
An enyzme that moves around phosphate groups.
How do polymers string together?
dehydration/condensation reaction
T/F: condenstaion reactions create covalent bonds
true
how do you determine D or L for carbon?
you look at the asymmetric carbon farthest from aldehyde group. note : carbons 1-5 are asymmetric
what do the properties of glycogen versus chitin tell us about the role of sugars?
sugars can be used for energy storage (glycogen) or structural support (chitin)
why do you put on weight as you age?
your body burns less energy and has a lower demand for carbs- if you keep eating the same amount, you will store them as fat
what are the partial charges on peptide bonds?
partially negative charge on that oxygen, partially positive charge on the hydrogen. this explains why this hydrogen is DOWN
sucrose
fructose + glucose
cholesterol
type of steroid, so its a lipid. OH coming off at the end means its partially soluble. precursor for steroid hormones
