Lec 13 and 14: Cellular Respiration I and II Flashcards
explain the diffference between metabolism, catabolism and anabolism
metabolism: all the chemical reactions in the body
catabolism: beaking down complex molecules
Anabolism: (endergonic) building of complex molecules
metabolism is the balance between the energy inputs and outputs of anabolism and catabolism
in what type of reactions is ATP used and made?
ATP is used in anabolic reactions
can be made in catabolic reactions
how is catabolism and anabolism coupled by ATP?
- catabolic reactions transfer energy from moleciles to ATP (releasing heat)
- these are simple molecules such as glucose, amino acids, glycerol and fatty acids.
- anabolic reactions transfer energy from ATP to complex molecules (releasing heat)
- these are molecules such as starch, proteins and lipids
cycle starts again
In starvation catabolism drops, explain what happens to the rate of anabolic processes
drop in catabolism means a drop in the break down of complex molecules
that provide energy for the production of ATP
therefore resulting in less amount of energy from ATP being provided
for the building of complex molecules (anabolic reactions)
rate of anabolic processes lowers
In liver cells (metabolises poisons) does anabolism or catabolism predominate?
catabolism
In a pancreatic cell producing digestive enzymes does anabolism or catabolism predominate
anabolism
What are the bodies main ways of storing energy
stores energy in nutrients
molecules such as glycogen (in liver) and triglycerides (in adipose tissue) store energy
why is ATP a good energy source for cells?
- contains high energy phospahte bond
- which can be released easily and quickly
what is oxidation
removal of electrons or hydrogen
/
addition of oxygen
decreasing potential energy
does oxidation or reduction take place in dehydrogenation reactions?
oxidation
what is NAD?
give the eqaution for the reduction of NAD
nicotinamide adenine dinucleotide
a derivative of the B vitamin niacin
what is FAD?
give the eqaution for the reduction of FAD
flavin adenine dinucleotide
derivative of the B vitamin riboflavin
how does phosphorylation (addition of P group) affect potential energy?
increases a molecules potential energy
what is subtrate level phosphorylation?
where does it occur
Transferring high-energy phosphate group from an intermediate directly to ADP
(occurs in the cytosol)
what is oxidative phosphorlyation?
where does it occur?
Remove electrons and pass them through electron transport chain to oxygen
occurs in the inner mitochondrial membrane
where is the only place Photophosphorylation takes place?
Only in chlorophyll-containing plant cells
what type of cell converts fructose to glucose
intestinal epithelial cells
what type of cells convert fructose and galactose to glucose?
hepatocytes
how does glucose move into the cells of the Gi tract?
by co transport
what is insulin and what is its function?
Insulin is a hormone
made by the pancreas
that allows your body to use glucose from carbohydrates in the food
for energy or to store glucose for future use.
Insulin helps keeps your blood sugar level from getting too high (hyperglycemia) or too low (hypoglycemia).
what happens in glycolysis?
steps 1-5
- Splits 6-carbon glucose into two 3-carbon molecules of pyruvic acid
- Consumes 2 ATP but generates 4
- Glucose –> Glucose 6-phosphate
(hexokinase, uses ATP and produces ADP + H+)
- Gluocse 6-phosphate –> Fructose 6-phosphate
(isomerase)
- Fructose 6-phosphate –> Fructose 1,6-biphosphate
(phosphofructase, uses ATP ad produces ADP + H+)
4a. Fructose 1,6-biphosphate –> Glyceraldehyde 3-phosphate
(aldolase)
4b. Fructose 1,6-biphosphate –> dihydroxyacetone phosphate
(aldolase)
- Glyceraldehyde 3-phosphate –> dihydroxy acetone phosphate
(triosephosphate isomerase)
what is the key regulator of glycolysis?
Phosphofructokinase
PFK
when are phosofructokinase levels high?
when ADP levels are high
how do ADP levels affect glycolysis
high ADP levels
indicate high phoshofructokinase acitivity
so high rate of glycolysis
/
low ADP levels
glucose is shunted away from glycolysis
to the glycogen storage pathway
what is Tarui disease?
where there is a lack of PFK
results in exercise intolerance, with pain, cramps and, occasionally, myoglobinuria (acute muscle breakdown leading to rust-colored urine).
A partial deficiency of phosphofructokinase in the red blood cells results in the breakdown of those cells and an increase in blood levels of bilirubin (a chemical found in red blood cells)