Animal Nutrition Exam 4

metabolism

metabolism

the sum processes of chemical changes in living cells by which energy and nutrients are provided for vital processes and activities and new materials are assimilated

anabolism

the constructive part of metabolism involving synthesis (creating new compounds)

catabolism

the destructive part of metabolism involving the release of energy and breakdown of complex materials

oxidation

loss of electrons

reduction

gain of electrons

Glycolysis

anaerobic (no O2) occurs in cytosol

Kreb's Cycle (TCA)

aerobic (needs O2) occurs in mitochondria

Oxidative phosphorylation

aerobic (needs O2) occurs in mitochondriaS

Stage 1 of Glycolysis

priming = uses 2 ATP Hexokinase (takes P from ATP to make Glucose-6-P) Phosphofructokinase (takes P from ATP to make Fructose 1,6-P)

Stage 2 of Glycolysis

production 4 ATP produced per glucose (total output of 2 ATP) generates 2 ATP, 2 NADH, and 2 pyruvate pyruvate kinase

NADH

electron transport yields 3 ATP per NADH

FADH2

electron transport yields 2 ATP per FADH2

Kreb's Cycle

pyruvate converted to acetyl-CoA (takes place for each pyruvate) produces 3 NADH, 2 FADH2, 1 GTP, 12 ATP for each acetyl-CoA (24 ATP total for 2 acetyl-CoA)

mitochondrion

function in the synthesis of ATP, major source of energy electron transport chain is on the inner membrane

oxidative phosphorylation

multi-enzyme complexes located in inner membrane inner membrane is impermeable to NAD, NADH, ATP and ADP proton-motive force

proton-motive force

build up of protons in the inter membrane space that drives ATP synthesis down a concentration gradient

ATP synthesis

ATP synthase catalyzes formation of ATP from ADP and P achieved from flow of protons form inter membrane space matrix NADH moves 10 protons FADH2 moves 6 protons 10 protons are needed for one full turn and will make 3 ATP

insulin

increases uptake of glucose, increases fat storage stimulates the formation of glycogen

Glycagon

Decrease uptake of glucose stimulates conversion of amino acids to glucose

Glucocorticoids

increases blood glucose (stress response)

Epinephrine

increases blood glucose decreases fat storage

Glycogenesis

process of making glycogen muscle and liver happens immediately following a meal caused by insulin

Glycogenolysis

breaking down glycogen caused by glucagon (increases glycogenolysis, increases blood glucose)

Gluconeogenesis

making glucose from non-CHO sources (the reverse of glycolysis) liver and kidney very important in ruminants (very little glucose is absorbed; propionate converted to glucose)

Simple lipids

makes up the largest % of lipids fats, oils, waxes

saturated lipids

single bonds only (as many H as possible)

unsaturated lipids

double bonds

gastric lipase

found in stomach; not very active in mature animals, functional in young animals

pancreatic liapse

primary fat digestion enzyme secreted with pancreatic juice secreted in an inactive form activated by Ca in lumen of SI

Bile

produced by liver and stored in gall bladder secreted in duodenum emulsification of fat arrange triglycerides for hydrolysis of lipase

lipase

cleaves fatty acid from glycerol backbone which exposes the hydrophilic heads

Micelle

free fatty acids and bile salt can interact with brush border and is the form which lipids are absorbed

chylomicron

made up of triglycerides, proteins, phospholipids, and cholesterol

fatty acid metabolism

oxidation to CO2 for ATP make glycolipids, phospholipids, and cell membranes lung alveolar integrity solubilize ADEK prostaglandin, sex hormones, adrenal hormones energy

cortisol

decreases fat storage

glucagon

decreases fat storage

growth hormone

decreases fat storage

fatty acid synthesis

produced from acetyl-CoA from CHO, proteins, VFAs, degraded fats occurs in cytosol fats are made 2 C at a time; process continues until fatty acid is 16 C long fatty acid synthase

B-oxidation

stepwise removal of 2C from fatty acids to make acetyl-CoA (2C) 16C = 8 acetyl CoA occurs in mitochondria

Ketosis

occurs when an animal has high energy demand increases fat catabolism = increases acetyl CoA which overloads Krebs cycle and it backs up converts acetyl CoA to acetoacetic acid (toxic), b-hydroxybutyric acid, and acetone blood pH decreases = metabolic acidosis

essential amino acids

phenylalanine valine threonine tryptophan isoleucine methionine histidine arginine leucine lysine

glucogenic amino acids

glycine, alanine, threonine, cystine, methionine converted to krebs cycle intermediates and converted to glucose

ketogenic amino acids

lysine, leucine converted to acetyl CoA and then to ketones

functions of absorbed proteins

nonessential amino acid synthesis tissue synthesis synthesis of enzymes and hormones deamination transaminiation

Protein synthesis

complex, involves many systems in body requires 20 ATP per peptide bond nucleic acids needed

protein turnover/degradation

constant process since there isn't a storage for amino acids combination of synthesis and degradation

Deamination

excess AA not needed for protein synthesis are catabolized break off NH3 from carbon skeleton

Urea

made with 2 ammonia (NH3) and carbon skeletonf

feeding experiment

feed feedstuff/nutrient, compare with standard source/control, measure production response answers: will they consume it and how well do animals perform questions: nutrient utilization

Digestion experiment

feed feedstuff/nutrient, sample feed and collect feces, analysis of feed and feces, calculate apparent digestibility coefficient (same equation as percent error) answers: nutrient absorption in GI tractme

metabolism experiment

feed feedstuff/nutrient, sample feed and collect feces, analysis of feed and feces, collect urine and analyze, calculate nutrient balance ((intake-(fecal+urine))/intake) x 100 answers: nutrients retained

How many total ATP are used in glycolysis?

2 ATP

What process breaks down glycogen?

Glycogenolysis

What enzymes control glycolysis?

hexokinase, phosphofructokinase, pyruvate kinase

Which pathway is responsible for the breakdown of glucose?

glycolysis

Urea is considered a non-protein nitrogen source.

true

What is a function of the stomach during fat digestion?

produce small droplets of fat

What is acetate converted to and what can it then be used to make?

acetyl CoA; ketones

What are the 2 products of deamination of amino acids?

NH3 and carbon skeleton

Microbes can use urea by aminiating then using the NH3 and carbon skeleton to make MCO protein.

true

Where does glycolysis occur?

cytosol

where does the kreb's cycle occur?

mitochondria

Goats require fatty acids in their diet

false

What must be continuously regenerated for glycolysis to continue?

NAD

After a carbohydrate heavy meal, what would you expect insulin and glucagon to do?

insulin decreases and glucagon increases

After a carbohydrate heavy meal, what would you expect gluconeogenesis and glycogenolysis to do?

stop

glycogen synthesis/glycogenesis will occur after a carbohydrate heavy meal.

true

What would be a route that nitrogen can be recycled back to the rumen?

saliva and bloodstream

what hormone would you expect to increase fat catabolism?

epinephrine

What do carbohydrate, fat, and protein metabolism have in common?

acetyl-CoA

What enzyme produces ATP from NADH, located on the inner mitochondrial membrane?

ATP synthase

What describes the over process of fat catabolism?

B-oxidation

What is produced by the liver, stored in the gall bladder, and secreted into the duodenum to aid in fat digestion?

Bile

What is a chylomicron composed of?

triglycerides, cholesterol, phospholipids, proteins

How is butyrate produced?

2 pyruvate -> 2 acetyl-CoA -> butyrate