Chapter 18 Flashcards
what is glucose and where is it made
glucose is a hexose (six carbon sugar)
made in photosynthesis
where does glycolysis occur and is it an anerobic or aerobic process
in the cytoplasm of a cell
anaerobic process so does not need oxygen
what is the end product of glycolysis
the glucose (six carbon sugar) is broken down into two pyruvate molecules (three carbon)
ATP and NAD is also released
four main stages to glycolysis
1)PHOSPHORYLATION- 2 molecules of ATP is required. 2 phosphates from the ATP attach to the glucose molecule forming hexose biphosphate
2)LYSIS- destabilizes the molecule which splits it into 2 triose phosphate molecules
3)PHOSPHORYLATION- another phosphate group is added to the triose phosphates which forms 2 triose biphosphates. (the phosphate groups come from free organic phosphates in the cytoplasm)
4)DEHYDROGENATION AND FORMATION- two triose biphosphate molecules are oxidized by removing hydrogen atoms to form two pyruvate molecules. NAD coenzymes accept the removed hydrogens (they are reduced so form NAD)
how is four ATP produced at the end of glycolysis
from the triose biphosphates at the end. this is an example of substrate level phosphorylation.
what happens to the ATP molecules at the end of glycolysis
its used to prime the next glycolysis. so net yield of ATP is two (4-2=2)
where does the link reaction happen
in the mitochondria’s matrix
what is the links reactions full name
oxidative decarboxylation
how does pyruvate enter the cell
through the mitochondrial matrix by active transport (carrier proteins)
what are the products of the link reaction and what do they do
Acetyl CoA- delivers the acetyl group to the next stage (Krebs cycle)
Co2- diffuse away or be removed as metabolic waste
NADH- used in oxidative phosphorylation to synthesize ATP
what do coenzymes do
transfer protons, electrons and functional groups between the reactions
example of two coenzymes
NAD and FAD
