What are some of the assumptions we make in the respiratory balance sheet? Are these valid enough to be applied to living systems? State comparisons between aerobic respiration and fermentation corresponding to respiration?
Answers
How is the energy released and stored during oxidation of compounds in respiration?
A.1. The energy released is directly collected in ATP in the form of chemical bonds. ADP + IP + energy → ATP This bond is broken and utilized whenever required ATP → ADP + IP + energy
Q.2. What is ‘Energy Currency’. Name the substance in animals and plants that act as an energy currency.
A.2. Energy is required by every cell to function. Energy currency releases and stores energy as and when required in the cell. In both plants and animals, ATP is known as the energy currency.
Q.3. In man and yeast, when does anaerobic respiration take place?
A.3. In man, it occurs when there is a lack of oxygen during cellular respiration, hence pyruvic acid is reduced to lactic acid by the lactate dehydrogenase. In yeasts also it occurs in the absence of oxygen.
Q.4. On oxidation, which of these releases more energy? Organize them in an arranging order.
a) 1gm of fat
b) 1gm of protein
c) 1gm of glucose
d) 0.5gm of protein + 0.5gm of glucose
A.4. 1gm of fat releases most energy. The following is the ascending order: 1gm of glucose < 0.5 gm of protein + 0.5gm of glucose < 1gm of protein < 1gm of fat.
Q.5. Fo-F1 particles are involved in the synthesis of?
A.5. They are both present in the inner mitochondrial membrane and are involved in the synthesis of ATP which is the energy currency of the cell.
Q.6. What is the product of the following?
a) Aerobic glycolysis in skeletal muscle
b) Anaerobic fermentation in yeast
A.6.
a) Pyruvic acid.
b) C2H5OH + CO2
Q.7. Where is the electron transport system – ETS is located in mitochondria of a cell?
A.7. Inter membrane space – It is the site of oxidative phosphorylation.
Short Answer Type Questions
Q.1. Why is a person fed with glucose or a fruit juice instead of a cheese sandwich that might give more energy, when a person is feeling dizzy?
A.1. Glucose gives instant energy as it is absorbed and reaches the blood. Cheese sandwich, however, requires time to digest and absorb. As sick people need an immediate energy supply, they are fed with glucose or given fruit juice.
Q.2. Aerobic respiration has more efficiency. Justify.
A.2. In this process, a single molecule of glucose can yield up to 36 ATP molecules. In anaerobic respiration or fermentation, there are only 2 molecules of ATP from every molecule of glucose, which in comparison is lesser than aerobic respiration. Hence aerobic respiration is more efficient.
Q.3. The final product of glycolysis is pyruvic acid. Write the three metabolic fates of the pyruvic acid in anaerobic and aerobic conditions as seen in the diagram below.