biochem Flashcards
name 3 forms of electrolytes
salts, acids and bases
name 2 molecules that reduce blood acidity
bicarbonate and ammonia help remove h+ ions
describe a catabolic reaction
breakdown complex molecules to similar ones, this would be an exothermic reaction, releasing heat and ATP, for example - cellular respiration
describe anabolic reactions
building complex molecules, endothermic reaction that requires energy input for example protein synthesis
what does ATP stand for
adenosine triphosphate
what is the dissociation reaction of atp
atp = adp + Pi
what is the energy source of direct phosphorylation
creatine phosphate (CP)
is direct phosphorylation aerobic or anaerobic
anaerobic, no oxygen used
what are the products of direct phosphorylation
1 ATP per CP + creatine
what is the duration of energy produced in direct phosphorylation
15secs
what is ck and what is its purpose
Creatine Kinase, enzyme that catalyses direct phosphorylation
what are the 3 ways that glucose can be obtained
- free glucose - from meals
- glycogenolysis- breakdown of glycogen in liver and muscles
- gluconeogenesis- formation of new glucose from other nutrients in liver
is direct phosphorylation catabolic or anabolic
catabolic, produces heat and ATP
what are the 3 link process in cellular respiration
glycolysis, Krebs cycle and electron transport chain.
name the 3 different groups of products from glycolysis
2 pyruvic acid molecules
2 Atp net molecules (4 overall but 2 were used)
2 NADH+H+ molecules
define the process of glycolysis
glucose is broken down into 2 pyruvic acid molecules
what are the 2 possible pathways after glycolysis
- if oxygen is restricted the pyruvic acid is converted to lactic acid and leads to muscle fatigue.
- if enough oxygen is present then pyruvic acid enters mitochondria for the Krebs cycle.
what must occur to allow pyruvic acid into the mitochondria
the transitional phase, enzyme pyruvate dehydrogenase converts each pyruvate acid molecule into acetyl-coenzyme A
what must occur to allow pyruvic acid into the mitochondria
the transitional phase, enemy pyruvate dehydrogenase converts each pyruvate acid molecule into acetyl-coenzyme A
what are the 3 products of the transitional phase
2 acetyle coenzyme A
2 NADH+H+
2 CO2
how many times does the Krebs cycle repeat for 1 molecule of glucose
the cycle is repeated 2 due to 2 pyruvic acid molecules converted to 2 acetyl-coenzyme A molecules that both then enter Krebs cycle
what are the products of one rotation of the Krebs cycle
3 NADH+H+
1 FADH2
2 CO2
1 ATP
what are overall products of Krebs cycle for 1 glucose molecules
6 NADH+H+
2 FADH2
4 CO2
2 ATP
which stage follows the Krebs cycle
electron transport chain
which 2 molecules are vital for electron transport chain and what do they do
NADH+H+
FADH2
they pass on their H+ ions and high energy electrons that they collected in redox reactions.
briefly describe the 4 stages of the electron transport chain
- NADH+H+ and FADH2 release their hydrogen ions to complex 1 and 2
- e- are passed from one complex to another. This process causes the complexes to be oxidised and reduced, pumping H+ ions into inter membrane space. This means outside membrane is positive and inside is negative and electrochemical gradient is formed
- at respiring enzyme IV 2 e- bind with 2H+ and 1/2 O2 molecule to form H2O
- Complex V is ATP Synthase and this allows H+ in intermmebrane space to flow back into matrix, as passing through ATP synthase the complex spins, causing Pi to join with ADP forming ATP
how many molecules of ATP are produced when NADH+H+ and FADH2 are reduced
NADH+H+ = 3 ATP
FADH2 = 2 ATP
before ETC there are 10 NADH+H+ molecules and 2 FADH2 molecules, how many ATP molecules are produced
NADH+H+ (3 atp) = (10X3)= 30 ATP
FADH2 (2atp) = (2X2) = 4 ATP
after ETC what are the overall molecules of ATP per 1 glucose
glycolysis (2ATP, 2NADH+H+) = 2 ATP
Transition ( 2NADH+H+) = 0 ATP
Krebs cycle (2ATP, 6NADH+H+, 2FADH2) = 2 ATP
ETC (10NADH+H+(30ATP) , 2FADH2(4ATP))=34 ATP
overall = 38 ATP
what can triglycerides be broken into
glycerol and fatty acids
how do fatty acids and glycerol both produce energy
both can be converted to acetyle-coenzyme A and used in Krebs cycle and then eventually the ETC
fatty acids produce many more ATP molecules compared to glucose but what is the downfall
full catabolism of fat requires a much greater volume of oxygen that is very rarely possible
what causes production of ketoacidosis
when very high fat use cause acetyl-conenzyme to be converted
when does production of ketoacidosis occur (3)
- low CHO diet
- Starvation
- uncontrolled diabetes mellitus
what are the effects of ketoacidosis production
Kussmauls respirations - deep + fast
ketone breath - smells like pear
ketones in urine
Eventually coma and death
when is catabolism of proteins used
- when all other methods are exhausted (starvation)
- used during prolonged exercise (marathon)
what two steps are required for catabolism of proteins
- in the liver the amine group of protein is removed (deamination) and amine group converted to ammonia and then urea
- remaining part of molecule may be converted to pyruvic acid and acetyl-coenzyme A, that can then be used in Krebs cycle and etc
when is the absorptive state
after being fed, following digestion
how long roughly is the body in absorptive state
12 hours each day, 4 hrs after each meal
what is the key hormone in absorptive state
insulin
describe post-absorptive state (fasting state)
nutrients have been absorbed/stored/used in biological processes
what stores do the brain rely on
they rely on glucose stores and cannot use fatty acid stores directly
what energy stores do RBCs rely on
RBCs have no mitochondria, rely solely on anearobic glycolysis
name the process of stored glycogen being broken into free glucose
glycogenolysis
name the process of stored triglycerides breakdown into glycerol and fatty acids
lipolysis
name the process of amino acids and lactates binding to form glucose
gluconeogenesis
what is the main hormone in post absorptive state
glucagon
what is the term for low levels of stored glycogen
hypoglycaemia
what structure is 50% of fat storage
subcutaneous adipose tissue
define term lipogenesis
injected glucose, FAs and AAs are converted to fat
which hormone influences lipogenesis
insulin
define term lipolysis
stored triglycerides in adipose are broken into glycerol and FAs
name 1 role of FAs
used for energy in m most cells (B-oxidation, krebs)
name 2 roles of glycerol
- converted to pyruvic acid/ acetyl-coenzyme A and used for ATP production
- undergo gluconeogenesis for maintaining blood glucose
which organ can produce non-essential Amino acids
liver
when Amin acids have be deanimated, the remaining molecule is ketoacid, name the 3 functions for ketoacid
- may enter Krebs cycle, fully catabolised for energy production
- converted to glucose
- converted to fat
name 3 roles of insulin
- promote glucose uptake in cells
- promote glucose conversion into glycogen
- inhibit glycogenolysis
- promote glucose conversion to triglyercides
- promote protein synthesis
- lower blood glucose
name 3 roles of glucagon
- promote glucose release from cells
- promote conversion of glycogen into glucose
3.inhibit glycogenesis
4.promote lipolysis - promote protein catabolism
- increase blood glucose
name an anabolic hormone
insulin
name a catabolic hormone
glucagon
