Biochemistry Basics Flashcards
Name three pathways involved in glucose metabolism
Glycolysis- catabolic
Gluconeogenesis- anabolic
Pentose phosphate pathway- catabolic
What are the end products of glycolysis and gluconeogenesis
Glycolysis: glucose -> pyruvate
Gluconeogenesis: pyruvate -> glucose
(Not exact reversals)
What makes the three main steps of glycolysis irreversible?
How does gluconeogenesis overcome this?
The three main steps of glycolysis involve large energy changes (-ΔG)
Gluconeogenesis overcomes this through different enzymes.
What do the enzymes hexokinase, phosphofructokinase-1 and pyruvate kinase contribute to glycolysis?
Hexokinase- catalyses phosphorylation of glucose to glucose-6-phosphate, uses ATP.
Phosphofructokinase-1- catalyses the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate.
Pyruvate kinase- catalyses the transfer of a phosphate group from phosphoenolpyruvate to ADP, yielding one molecule of pyruvate.
Fatty acids can be oxidised to form what?
This product then enters the citric acid cycle via?
Fatty acids can be oxidised to acetyl coA and enter the citric acid cycle via β-oxidation.
How many amino acids are there in total?
What are the five different groups these amino acids fit within?
There are twenty amino acids in total.
The groups are: non-polar aliphatic, polar uncharged, aromatic, positively charged, negatively charged.
Name the seven non-polar aliphatic amino acids.
Glycine, Leucine, Isoleucine, Valine, Proline, Alanine and Methionine.
Name the five polar uncharged amino acids.
Serine, Threonine, Cysteine, Glutamine and Asparagine.
Name the three aromatic amino acids.
Phenylalanine, Tyrosine, Tryptophan.
Name the three positively charged amino acids.
Lysine, Arginine and Histidine
Name the two negatively charged amino acids.
Glutamic acid and aspartic acid.
Name the nine essential amino acids.
Histidine, Valine, Leucine, Methionine, Isoleucine, Lysine, Tryptophan, Phenylalanine and Threonine.
What is the difference between deoxyribonucleotides and ribonucleotides.
Deoxyribonucleotides have a hydrogen atom bonded to the C2 of the Pentose rather than a hydroxyl group.
What are the two types of nucleotide biosynthesis?
De novo synthesis- begins with precursors: amino acids, ribose-5-phosphate, CO2 and NH3
Salvage pathways- recycle free bases and nucleosides released from nucleic acid breakdown.
What does de novo synthesis require?
PRPP
