Determine whether each phrase describes glucokinase, hexokinase isozymes I–III, or all hexokinase isozymes. Note: Assume that the kinetic behavior of hexokinase isozymes in vivo is similar to in vitro. Glucokinase (hexokinase IV) Hexokinase I, II, or III All hexokinase isozymes (I–IV)

B) It is not sensitive to inhibition by glucose-6-phoaphate(remians active even when glucose is abundant and is not effected by allosteric inhibition.)

C) Subcellular localisation is regulated by fructose-6-phosphate (when fructose -6-phosphate concentration is high causes localisation of hexokinase IV to nucleus as it is inhibited by high Fructose-6-phosphate concentration and releases into cytosol when glucose concntration is high)

2. Hexokinase I II or III :

A)Present in tissues that sense blood glucose levels.

B) When blood glucose levels fall below normal range maintains maximum velocity. ( since it has high affinity for glucose and low glucose concentration favors low Km for hexokinase I II III) .

okpalawalter8 okpalawalter8 · Answer 2 · 2021-12-22T10:52:08+01:00

Answer:

Glucokinase (Hexokinase IV):

- Subcellular localization is regulated by frutose 6-phosphate

- present in tissues that sense blood glucose levels

- not sensitive to inhibition by glucose 6-phosphate

- plays an important role in liver regulation of blood glucose level

Hexokinase I, II, or III

- when blood glucose levels fall below normal range, maintains maximum velocity

- when blood glucose is low, will cause cells to trap glucose by phosphorytation

- wil be saturated by normal blood glucose concentrations

All hexokinase isozymes (I-IV)

- will phosphorylate several hexoses including glucose