biochem 2 Flashcards
the other molecules attached to carbon skeleton in living things are called
the functional group
3 forms carb
monosaccharides
disaccharides
polysaccharides
structure of disaccharide
2 monosaccharides
structure of polysaccharide
10-100s monosaccharides
type of reaction that joins monosaccharides together
dehydration reaction
type of bond joining all carbs
glycosidic
ex 5 monosaccharides
glucose fructose galactose deoxyribose ribose
glucose + fructose =
sucrose
sucrose made of
glucose & fructose
glucose + galactose =
lactose
lactose made of
glucose + galactose
glucose + glucose =
maltose
maltose made of
glucose + glucose
3 ex of polysaccharides
glycogen
starch
cellulose
structure of glycogen, starch & cellulose
glucose chains
monosaccharides are grouped into families, named after
no. of carbon atoms in the chain
tri-oe
pentose
hexose
most common polysaccharide in body is
glycogen
are polysaccharides soluble
no
do polysaccharides taste sweet
no
the major dietary source of carbohydrate is
starch
starch made up of 2 polysaccharides called
amylose
amylopectin
structure of glycogen
polysaccharide made of glucose
function of glycogen
primary short term energy storage in body
glycogen mostly made by
liver and muscles
what is cellulose
structural material of plants
why can’t we digest cellulose
we lack cellulase
3 carb functions
primary fuel for energy production
stored energy: glycogen
3 fibre - bowel function
digestible carb in the diet comes from what 3 sources
sugars
starch
glycogen from animal protein
4 stages carb digestion
1 - mouth: salivary amylase splits glycosidic bonds
2 - stomach: digestion stops due to pH
3 - pancreatic amylase continues digestion in small intestine
4 - mucosal cells of jejunum brush border secrete sucrase, amylase lactase to complete digestion
glucose from carb digestion is used for 4
Production of: ATP glycogen triglycerides amino acids
lipids like carbohydrates contain which 3 elements
carbon
hydrogen
oxygen
lipids are hydrophobic because they have fewer what that carbs
OH groups
how do lipids move around body
made more soluble by attaching to proteins = lipoproteins
main form dietary fat
triglycerides
structure triglyceride
1 glycerol
3 fatty acid
what reaction bonds triglycerides together
dehydration synthesis reaction
what bonds to fats have
ester bond
triglycerides are broken down by what reaction
hydrolysis reaction
4 functions of fats/triglycerides/lipids
1 source of energy (less efficient than carb)
2 storage excess calories
3 insulation
4 protection
structure of saturated fats
single covalent bonds between each fatty acid carbon atom
behaviour of saturated fat at room temp
solid - can pack tightly
structure monounsaturated fat
double covalent bond between 2 carbons in carbon chain
shape of monounsaturated fat
bent due to 1 double bond
behaviour of monounsaturated fat at room temp
liquid as molecules can’t pack tightly
structure polyunsaturated fats
several double covalent bonds in carbon chain
shape of polyunsaturated fats
kinked
behaviour of polyunsaturated fats at room temp
liquid
how to find omega carbon in fatty acid
last c in chain
how to find alpha carbon in fatty acid
1st c after carboxyl join (cooh)
fatty acids are named according to the
closest double bond to the omega carbon
a double bond in a fat has two possible configurations
cis
trans
cis or trans found in nature
cis
configuration and shape of cis fat
H atoms on same side of double bond
bent
config and shape of trans fat
H atoms on separate side of double bond
straight
2 ways cis fats turn to trans fats
high temp
hydrogenation processes margarine
what type of fat are EFAs
polyunsaturated
can body make omega 3/6 from scratch
no
only converts from 1 to another
omega 3 family
LNA
EPA
DHA
Eicosanoids
LNA full name/source
alpha-linolenic acid
veg oil, flax, nuts
EPA full name/source
eicosapentaenoic acid
fish oil
DHA full name/source
docosahexaenoic acid
fish oil
omega 6 family
LA
GLA
AA
Eicosanoids
full name/source LA
Linoleic Acid
veg oil, nuts seeds
GLA full name source
Gamma-Linolenic Acid
borage/primrose oil
AA full name/source
arachidonic acid
meat
6 functions EFA
1 fluidity/chemical activity cell membrane
2 help make lubricants for joints
3 transport cholesterol in blood
4 needed by tissues of retina, adrenals, brain, testes
5 ensure proper nerve transmission esp in brain
6 prostaglandin synthesis
polyunsaturated fats are prone to becoming what
free radicals
radical formation is accelerated by
light
oxygen
heat
2 safety considerations for polyunsaturated fats
never cook with
keep in glass bottle in fridge
where are lipoproteins sinthesised
in liver
which lipoprotein carries triglycerides from intestines to liver, skeletal muscles and adipose tissue
chylomicrons
which lipoprotein carries cholesterol to the liver
HDL
which lipoprotein carries triglycerides from the liver to adipose tissue
VLDL
which lipoprotein carries cholesterol from liver to all cells of body
LDL
