Biochem Flashcards
What is the deltaG (free energy) in an exergonic and an endergonic reaction and which can occur spontaneously?
Exergonic: -ve (can occur spontaneously)
Endergonic: +ve
Where are steroid hormones synthesised?
Smooth ER
Where are polypeptides synthesised?
Rough ER
What does the golgi apparatus do?
Distributes materials from the ER and modifies proteins
What is a eukaryote and a prokaryote?
Eukaryote = a normal cell Prokaryote = single organism without a well defined nucleus
(YOUkaryote = what you are)
What is included in a nucleoside and a nucleotide?
Nucleotide = phosphate + base + sugar Nucleoside = base + sugar
(NucleoSide = Sugar)
What are the 3 types of RNA and their purpose?
rRNA = ribosomal RNA (combines with proteins to form ribosomes) tRNA = transfer RNA (collects amino acids and transports them to the ribosomes) mRNA = messenger RNA (carries DNA code to ribosomes for translation)
What RNA subunit type synthesises all mRNA?
Pol II
What are transcription factors?
Turn on and off genes during translation to RNA/proteins
Which areas of a gene and coding and non-coding?
Coding = exons Non-coding = introns
What provides the energy for protein synthesis?
GTP
What are enzymes called with and without a cofactor?
Without = apoenzymes With = holoenzymes (cofactor = nonprotein compound required for the enzymes activity)
(WHOLEoenzyme = with)
What effect do competitive and non-competitive binding have upon the Vmax and Km?
Competitive: Vmax constant, Km varies
Non-Competitive: Km constant, Vmax varies
How does glucose enter cells?
By facilitated diffusion through GLUT
What is the difference between catabolism and anabolism?
Anabolism = requires energy Catabolism = produces energy (breakdown of molecules)
What enzyme phosphorylates glucose?
Hexokinase
Where are GLUT1, 2, 3 and 4 found?
GLUT1: RBCs
GLUT2: GI tract
GLUT3: neurones
GLUT4: muscle cells
Describe the citric acid cycle
Acetyl CoA Citrate Isocitrate (=>CO2, NAD=>NADH+H) Alpha-ketoglutarate (=>CO2, NAD=>NADH+H) Succinyl CoA (GDP=>GTP) Succinate (FAD=>FADH2) Fumarate (H2O=>) Malate (NAD=>NADH+H) Oxaloacetate
What are the products of each citric acid cycle?
3NADH+H
1FADH2
2CO2
1GTP (ATP)
Which enzyme of the TCA cycle is not in the matrix of the mitochondria?
Succinate dehydrogenase (on inner mitochondrial membrane) (Succinate => fumarate)
How is ADP converted to ATP?
Flow of electrons back across the mitochondrial membrane into the mitochondria drives phosphorylation through ATPsynthase (FiFoATPase)
What is the total amount of ATP produced from internal respiration?
30-32
What is the electron carrier during oxidative phosphorylation?
Oxygen
