Glycolysis Flashcards
1
Q
How does glucose enter the cell
A
- carrier proteins: glucose transporters
- uses insulin to help with this in tissue cells, by binding to receptors on cells, insulin lets GLUT4 molecules come
2
Q
1)
A
- glucose enters the cell through glut4 molecules
- kinase enzyme adds PO4 to lock glucose in, and form g6p
- costs 1 ATP
3
Q
2)
A
- conversion of g6p to f6p
- conversion from aldose sugar to ketose sugar
- phospho isomerase=enzyme
4
Q
3)
A
- f6p gains another phosphate
to produce f-1,6-bp - enzyme pfk is a major regulator
- costs 1 ATP
5
Q
4)
A
- cleaving
- f-1,6 is split into half
- 6C- 2 3Cs
- produces g3p and DHAP
- enzyme: aldolase
6
Q
5)
A
- converting DHAP to g3p
- enzyme: triose phosphate isomerase
7
Q
How many ATP have been lost in the energy investment stage?
How many ATP have been gained?
A
lost: 2 ATP (1,3)
gained: 0 ATP
8
Q
6)
A
- oxidize g3p
- electrons go to nad+ to become nadh, reducing nad+
- g3p gains a phosphate to become 1,3-bpg
9
Q
7)
A
- substrate level phosphorylation
- 1,3-bpg has a po4 removed
- adp converted to atp
- po4 is moved directly by enzymes
- produces 3-pg
- gain of 2 atp
10
Q
steps 8) and 9)
A
- movement of po4 group, to make it more accessible
- 3-pg — 2-pg — pep
11
Q
Differences between step 8) and 9)
A
In step 8, 3PG is converted to its isomer 2PG
In step 9, 2-PG loses a molecule of water becoming PEP
12
Q
10)
A
- substrate level phosphorylation
- PEP has a po4 removed
- ADP is converted to ATP
- PO4 is moved directly by enzymes
- production of pyruvate or pyruvic acid
- gain of 2 atp
13
Q
energy yield in anaerobic glycolysis
A
- 4 atp created
- net gain of 2 atp
- 2 nadh’s carrying electrons
- no o2 required
- 1 nad+
14
Q
which steps of glycolysis are irreversible?
A
1,3,10 (possibly 7)
15
Q
how many times does energy harvesting occur?
A
twice
