Chapter 14 – Respiration In Plants

The ultimate electron acceptor of respiration in an aerobic organisms is:

• a.Cytochrome
• b.Oxygen
• c.Hydrogen
• d.Glucose

Phosphorylation of glucose during glycolysis is catalysed by

• a.Phosphoglucomutase
• b.Phosphoglucoisomerase
• c.Hexokinase
• d.Phosphorylase

Pyruvic acid, the key product of glycolysis can have many metabolic fates. Under aerobic condition it forms

• a.Lactic acid
• b.CO2 + H2O
• c.Acetyl CoA + CO2
• d.Ethanol + CO2

Electron Transport System (ETS) is located in mitochondrial

• a.Outer membrane
• b.Inter membrane space
• c.Inner membrane
• d.Matrix

Which of the following exhibits the highest rate of respiration?

• a.Growing shoot apex
• b.Germinating seed
• c.Root tip
• d.Leaf bud

Mitochondria are called powerhouses of the cell. Which of the following observations support this statement?

• a.Mitochondria synthesise ATP
• b.Mitochondria have a double membrane
• c.The enzymes of the Krebs cycle are found in mitochondria.
• d.Mitochondria are found in almost all plants and animal cells.

The end product of oxidative phosphorylation is

• a.NADH
• b.Oxygen
• c.ADP
• d.ATP+H2O

Match the following and choose the correct option from those given below. Column I Column II A. Molecular oxygen i. α - Ketoglutaric acid B. Electron acceptor ii. hydrogen acceptor C. Pyruvate dehydrogenase iii. cytochrome C D. Decarboxylation iv. acetyl Co A Options

• a.A-ii, B-iii, C-iv, D-i
• b.A-iii, B-iv, C-ii, D-i
• c.A-ii, B-i, C-iii, D-iv
• d.A-iv, B-iii, C-i, D-ii RESPIRATION IN PLANTS 79

Why is respiratory pathway referred to as an amphibolic pathway? Explain.

We commonly call ATP as the energy currency of the cell. Can you think of some other energy carriers present in a cell? Name any two.

ATP produced during glycolysis is a result of substrate level phosphorylation. Explain.

Do you know any step in the TCA cycle where there is substrate level phosphorylation. Which one?

A process is occurring throughout the day, in ‘X’ organism. Cells are participating in this process. During this process ATP, CO2 and water are evolved. It is not a light dependent process.

• a.Name the process.
• b.Is it a catabolic or an anabolic process?
• c.What could be the raw material of this process?

When a substrate is being metabolized, why does not all the energy that released in one step. It is released in multiple steps.What is the advantage of step-wise release?

Respiration requires O2.. How did the first cells on the earth manage to survive in an atmosphere that lacked O2?

It is known that red muscle fibres in animals can work for longer periods of time continuously. How is this possible?

The energy yield in terms of ATP is higher in aerobic respiration than during anaerobic respiration. Explain.

RuBP carboxylase, PEP carboxylase, Pyruvate dehydrogenase, ATPase, cytochrome oxidase, Hexokinase, Lactate dehydrogenase. Select/choose enzymes from the list above which are involved in

• a.Photosynthesis
• b.Respiration
• c.Both in photosynthesis and respiration

How does a tree trunk exchange gases with the environment although it lacks stomata?

Write any two energy yielding reactions of glycolysis.

Name the site (s) of pyruvate synthesis. Also, write the chemical reaction wherein pyruvic acid dehydrogenase acts as a catalyst.

Mention the important series of events of aerobic respiration that occur in the matrix of the mitochondrion and in the inner membrane of the mitochondrion.

Respiratory pathway is believed to be a catabolic pathway. However, nature of TCA cycle is amphibolic. Explain.