Glycolysis Flashcards
What is Glycolysis?
The breakdown of glucose to smaller molecules, producing ATP
Where does Glycolysis take place?
In the cytoplasm of cells
What are 3 chemical groups and their ends often involved in metabolism?
Aldehydes - C=0-H Carbonyl end (Acetaldehyde)
Ketone- C=O Carbonyl in middle (Acetone)
Carboxyl - C=O-OH end (e.g Acetic acid)
What kind of state can sugars and glucose sit in?
Equilibrium
What does all sugars end in?
-ose
What are the 2 types of glucose and what one is the most naturally occurring?
D and L Glucose - D is the most naturally occurring
What does each sugar have in the centre?
A chiral centre
What happens going from an open chain sugar to a cyclic one?
Water is lost and there are 2 different sugars that can be produced depending on what Hydrogen is lost
How many members does glucose have in its ring?
6 (pyranose ring)
How many members does fructose have in its ring?
5 (furganose ring)
Where is Fructose sugar most commonly found ?
In lots of fruits
Where is the carbonyl group which is attacked to form a cyclic structure positioned?
Carbon 2
What is the basic structure of an amino acid?
NH3+
|
H-C-COO-
|
R1What happens in proteins to form a peptide bond?
The amino group of one amino acid joint to the carboxyl group of its neighbour
What type of acid is common in metabolism?
Keto acids - made from metabolising fats (NOT KETOS IN BODY!)
What does Glycolysis do?
Converts glucose to pyruvate and makes 2 ATP
What are the steps of Glycolysis?
1) . Phosphorylation -(consumes 2 ATP) and traps Glucose in the cell because once it is ionised to Glucose-6-P it is unable to cross the cell membrane
2) . Isomerization - Glucose-6-P covered to Fructose-6-P
3) . Phosphorylation - (consumes 2 ATP) and forms a hexose diphosphate that can be split into two phosphorylated 3-carbon compounds
4) Cleavage and Isomerisation - Forms 2 phosphorylated 3-carbon compounds, then allows dihydroxyacetone-P to be converted to glyceraldehyde-3-P which can be metabolised
5). Oxidative phosphorylation - Glyceraldehyde-3-P is
simultaneously oxidized and
phosphorylated
Hydrogen and electrons from
glyceraldehyde-3-P are
passed to nicotinamide
adenine dinucleotide (NAD+)
6). Transfer of phosphate
- ATP production;
2 molecules of ATP/molecule of glucose consumed
7) . Molecular arrangement
- Phosphate group moved from one position to another (isomerisation)
8) . Dehydration
- Favours transfer of phosphate to ATP
9) . Transfer of Phophate
- ATP production; 2 molecules of ATP/molecule of glucose consumed
What is the full name for NAD?
Nicotinamide Adenine Dinucleotide
How do we get from NAD+ to NADH and vice versa?
NAD+ –Reduce–> NADH
(Oxidative agent)
NADH –Oxidise–> NAD+
(Reducing agent)
Where does the nicotinamide part of NAD+ come from?
Vitamin B3 (Niacin)
How do we get Vitamin B3 and what conditions are cause by a lack of it?
Needs to be provided in our. diets
Lack of Niacin causes. Pellagra - sensitivity to sunlight, dermatitis, alopecia, glossitis, weakness, ataxia
What happens to NAD+ during aerobic conditions?
NAD+ is regenerated because NADH passes the electrons and the hydrogen atoms which is receives from glyceraldehyde-3-P through the Electron Transfer Chain which combines three with molecular oxygen and water
What happens to NAD+ during anaerobic conditions?
Without molecular oxygen NADH builds up and because NAD+ cannot be regenerated glycolysis is halted if this continues
So NADH is re-oxidised by reducing pyruvate to Lactate
What builds up making muscles ache?
Acid from metabolism NOT from Lactate
