5. Energy Transfers EQs
暂无描述。系统推荐的高质量记忆内容，适合每天坚持背诵学习。
卡片预览 (24 张)
Give the function of a mitochondrian (1 mark)
Produce ATP for respiration
The mitochondria in muscles contain many cristae. Explain the advantage of this (2 marks)
• large surface area • more enzymes for ATP production
Explain why converting pyruvate to ethanol is important in allowing the continued production of ATP in anaerobic respiration (2 marks)
• Allows NAD to be re-formed • so more glucose can be converted into pyruvate
Give two ways in which anaerobic respiration of glucose in yeast is similar to anaerobic respiration of glucose in a muscle cell (2 marks)
• ATP formed • Pyruvate formed
Give two ways in which anaerobic respiration of glucose in yeast is different to anaerobic respiration of glucose in a muscle cell (2 marks)
• Yeast = ethanol Muscle = lactic acid • CO2 released by yeast, not muscle
In anaerobic respiration, what is the net yield of ATP molecules per molecule of glucose? (1 mark)
2
Describe how NAD is regenerated in anaerobic resp in yeast cells (1 mark)
reduced NAD is oxidised
Explain why most of the energy is provided by anaerobic respiration rather than aerobic? (2 marks)
• high respiration rate • so unable to supply enough oxygen to muscles
The athlete continues to breathe deeply for several minutes after the race ends. Explain why this is necessary (2 marks)
• oxidise lactate into pyruvate • by aerobic respiration
Explain why some muscles become fatigued when insufficient oxygen is available (2 marks)
• increased conc of lactate • lowers pH
Without oxygen, less ATP is produced by respiration. Explain why (2 marks)
• only glycolysis can take place • only produces 2 ATP
When glucose is respired what happens to the energy which is not incorporated into ATP? (1 mark)
released as heat
Describe how acetylcoenzyme A is formed in the link reaction (2 marks)
1.Oxidation of pyruvate and carbon dioxide released; 2.Addition of coenzyme A.
In link reaction pryruvate is converted to a substance with 2 carbon atoms. Describe what happens in this process (2 marks)
• decarboxylation • acetyl coenzyme A produced
Apart from respiration, give three uses of ATP in a liver cell (3 marks)
• Cell division • Active transport • Phagocytosis
Aerobic respiration produces more ATP per molecule of glucose than anaerobic respiration. Explain why. (2 marks)
• Oxygen is final electron acceptor • In aerobic respiration oxidative phosphorylation • In anaerobic respiration only glycolysis occurs which only produces 2 ATP
Explain the purpose of the strip of filter paper in the potassium hydroxide solution in a respirometer (1 mark)
to increase surface area for carbon dioxide absorption
The level of liquid in the right-hand side of the manometer went down during the experiment. Explain why. (2 marks)
• oxygen is used and carbon dioxide emitted is absorbed; • so decrease in volume
What measurements are needed to calculate the rate of oxygen uptake by the snails in mm3 g –1 h –1 ? (3 marks)
• change of level of (manometer) liquid over time; • mass of snails; • time interval;
Describe the role of oxygen in aerobic respiration (2 marks)
• final acceptor for hydrogen: • to form water;
Describe how ATP is made in mitochondria? (6 marks)
• ATP and reduced NAD produced in Krebs cycle • Electrons produced from reduced NAD • Electrons pass along electron transport chain • Releasing energy for ADP + Pi • Protons move into intermembrane space • By ATP synthase
Explain why oxygen is needed for the production of ATP on the cristae of the mitochondrion (3 marks)
• ATP formed as electrons pass along transport chain • Oxygen is terminal electron acceptor to form water • However if no oxygen then electrons cannot be accepted
Describe the part played by the inner membrane of a mitochondrion in producing ATP (3 marks)
• Electrons transferred down electron transport chain • Provide energy to take protons into space between membranes; • Protons pass back, through membrane into matrix through ATP synthase; • Energy used to combine ADP and phosphate to produce ATP;
In photosynthesis, which chemicals are needed for the light-dependent reaction? (1 mark)
NADP, ADP, Pi and water;