Metabolism Flashcards
Metabolism defenition
Sum of all reactions (catabolic and anabolic) in living things with the use of enzymes
Anabolism definition + 3 examples
Synthesis of simple molecules forming more complex molecules e.g. protein synthesis, DNA synthesis, condensation reactions
Catabolism definition + 3 examples
Breakdown of complex molecules into simpler molecules by hydrolysis e.g. digestion of food, cell respiration, hydrolysis reactions
What does ATP stand for?
Adenosine triphosphate
What biochemical processes use ATP?
B - Biosynthesis of macromolecules
A - Active transport
N - Nerve transmission
G - Growth and repair
M - Movement (muscle contraction)
E - Emission of light (bioluminescence)
Structure of ATP
Same structure as a nucleotide with two more phosphates bonded to original phosphate
How does ATP release energy?
ATP breaks bond with third phosphate to release energy, and it becomes adenosine diphosphate.
Is ATP solube or insoluble in water?
Solube, which aids with transportation
Breathing definition
Air moving in and out of lungs
Ventilation definition
Mechanisms which allow air to move in and out of lungs
Respiration
Breakdown of carbohydrates to release energy
What are the differences between aerobic and anaerobic respiration?
Anaerobic occurs in cytoplasm, aerobic in mitochondria.
Aerobic requires oxygen, anaerobic does not.
Anaerobic respiration equation in mammals (chemical and word)
Glucose –> lactic acid
C6H12O6 –> 2C3H6O3
Anaerobic respiration equation in yeast and bacteria (chemical and word)
Glucose –> Ethanol + CO2
C6H12O6 –> 2C2H5OH + 2CO2
What are carrier molecules and what are their functions?
FAD and NAD+ are carrier molecules
Organic molecules which can pick up and drop off electrons and protons.
Function is to act as oxidising or reducing agent in the process of cellular respiration
Equation for reduction of NAD+
NAD+ + 2H+ –> NADH + H+
Equation for reduction of FAD
FAD + 2H+ –> FADH2
What are the four stages of respiration, briefly outlining what they do and where they take place?
1) Glycolysis - forms pyruvate from glucose, takes place in cytoplasm
2) Link reaction - forms Acetyl CoA from pyruvate, takes place across mitochondrial membrane
3) Krebs cycle - forms CO2, ATP, reduced FAD and NAD etc. from Acetyl CoA, takes place in mitochondrial matrix
4) Electron transport chain - forms H2O and ATP, takes place in inner mitochondrial membrane
What are the 3 stages of glycolysis for one glucose moleucle?
1) 6C sugar is phosphorylated, which uses two ATP which turn into ADP. It ends up being Fructose 1, 6- bisphosphate
2) Fructose 1, 6- bisphosphate goes through lysis and splits into triose phosphate
3) Both triose phosphate are oxidised by NAD+ and two ATP are produced for each triose phoshate. The funal product is 2x pyruvate
What are the 3 stages of link reaction for one glucose moleucle?
1) Pyruvate passes through mitochondrial membrane by a carrier protein and goes through decarboxylation (loses a CO2)
2) It is then oxidised by NAD+
3) Coenzyme A bonds with the molecule and Acetyl CoA is the final product
WHOLE PROCESS HAPPENS TWICE BECAUSE 2 PYRUVATE ARE FORMED FROM ONE 6C SUGAR
What are the 4 stages of the Kreb’s cycle for one glucose moleucle?
1) CoA is removed from 2C Acetyl and Acetyl bonds with Oxaloacetate (end product) to form 6C citrate
2) 6C citrate is decarboxylated and oxidised by NAD+ and forms a 5C molecule
3) 5C molecule is decarboxylated and oxidised by NAD+ to form a 4C molecule
4) 4C molecule is oxidised twice by NAD+ and FAD to form 4C oxaloacetate. ATP is also formed in this step
WHOLE PROCESS HAPPENS TWICE BECAUSE 2 ACETYL COA ARE FORMED FROM ONE 6C SUGAR
What are each step in Kreb’s cycle controlled by?
Specific enzymes for each step
What are the 5 stages of the Oxidative phosphorylation cycle for one glucose moleucle?
1) NADH and FADH2 have protons (H+) removed by dehydrogenase enzyme. H atoms then split into protons and electrons
2) e- move along electron transport chain, moved by proteins called electron carriers. e- lose energy at each carrier
3) Energy lost from e- is used to pump H+ from mitochondrial matrix to intermembrane space, making a H+ gradient with higher conc. In interm space. (electrochemical gradient)
4) H+ move down EC gradient into matrix via ATP synthase. This produces ATP from ADP - CALLED CHEMIOSMOSIS
5) H+ from chemiosmosis (and all other stages), e- from ETC and O2 from bloodstream combine to form water - which is known as final electron acceptor
What is the net ATP production in aerobic and anaerobic respiration?
Aerobic - 36
Anaerobic - 2
