Biochem 1 - homeostasis Flashcards
How long do glycogen stores last
12-24 hours
What is the energy for ATP synthesis derived from
Oxidation of glucose, long chain fatty acids and amino acids
What can the brain use as fuel
Glucose and ketone bodies
Hormones that cause increased blood glucose
Glucagon, catecholamines, cortisol, growth hormone
-> glycogenolysis and gluconeogenesis
Hormones that caused reduced blood glucose
Insulin -> glycolysis and glycogen/fat synthesis
How does glucose enter cells
Facilitated diffusion down conc gradient
Gluts
Glut 1
rbcs, muscle, brain, kidney, colon, placenta, foetal tissue
High affinity
Glut 2
Liver, pancreatic beta cells
Low affinity
Glut 3
Brain
High affinity
Glut 4
Skeletal muscle, adipose tissue (insulin sensitive)
Fairly high affinity
Immediate effects of insulin
Increase rate of glucose uptake in muscle/adipocytes
Modulate activity of enzymes of glucose metabolism
Occur in minutes
Long term effects of insulin
Increased expression of liver enzymes that synthesise glycogen
Increase expression of enzymes that synthesise TGs
Inhibit lipolysis in adipose tissue
Functions as a growth factor for fibroblasts
Occur over several hours
Where does Pentose phosphate pathway branch from glycolysis
G-6-P
Products of pentose phosphate pathway
Ribose phosphate - for RNA/DNA synthesis
NADPH
Which tissues are rich in PPP enzymes
Tissues involved in biosynthesis - liver and adipose tissue
