Biology

Plant Transport and Physiology

2,012 Questions

Access a comprehensive set of questions on plant transport mechanisms and physiological adaptations. Topics include water movement, translocation of food, and plant responses to external stimuli. These biology questions are essential for medical entrance exams and other science competitive tests.

Xylem and phloem transportTranspiration and evaporationPlant adaptationsGeotropic and phototropic responsesWater absorption by rootsRespiration in roots

Plant Transport and Physiology Questions

Multiple choice

Which of the following statements is/are false?

a. The opening and closing of stomatal pores is controlled by the guard cells. b. Green plants take carbon dioxide from air for photosynthesis. c. Cytoplasm is the site of photosynthesis in the cell of a leaf.

  1. Only a

  2. Only a and b

  3. Only b

  4. Only b and c

  5. Only c
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is the correct option as this statement is false. Chloroplast is the site of photosynthesis in the cell of a leaf.

Multiple choice

Which of the following statements are correct about C4 plants?

A. CO2 fixation occurs twice. B. PEP acts as CO2 acceptor in bundle sheath. C. Leaf anatomy is of Kranz type. D. They require 18 ATP for synthesis of one molecule of glucose.

  1. A and B

  2. A and C

  3. B and C

  4. B and D

  5. C and D
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This option is correct because in C4 plants, CO2 fixation occurs twice, once in mesophyll cells to form oxaloacetic acid and another in bundle sheath cells to form 3-phosphoglyceric acid. Kranz-type leaf anatomy is found in C4 plants.

Multiple choice

Match the following:

 
1. Roots A. are responsible for reproduction.
2. Leaves B. bears branches, leaves, fruits and flowers.
3. Flowers C. are the food factories of the plant.
4. Stem D. fix the plant to the soil and absorb water and minerals from the soil.

  1. 1 - A, 2 - C, 3 - D, 4 - B

  2. 1 - C, 2 - A, 3 - B, 4 - D

  3. 1 - C, 2 - B, 3 - A, 4 - D

  4. 1 - D, 2 - C, 3 - A, 4 - B

  5. 1 - A, 2 - B, 3 - C, 4 - D
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is a correct answer because roots  fix the plant to the soil and absorb water and minerals from the soil, leaves are food factory of the plant, flowers are responsible for the reproduction, and stem bears branches, leaves fruits and flowers.

Multiple choice

What does climacteric mean?

  1. Sudden increase in respiration during fruit ripening

  2. Sudden premature fall of all the fruits

  3. Shedding of flowers before anthesis

  4. Climax vegetation

  5. Sudden increase in the rate of photosynthesis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Climacteric refers to the sudden increase in respiration during fruit ripening.

Multiple choice

Why does a plant cell not burst when it is placed in a hypotonic solution?

  1. Due to the presence of cell wall

  2. Due to the presence of cytoplasm

  3. Due to the presence of plasma membrane

  4. Due to the presence of large vacuoles
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cell walls permit the cells of plants, fungi and bacteria to withstand very dilute (hypotonic) external media without bursting. In such media, the cells tend to take up water by osmosis.

Multiple choice

If a plant cell is placed in deionised water, the water potential of that cell becomes

  1. more positive because the pressure potential becomes more positive

  2. more positive because the osmotic potential becomes more negative

  3. more negative because the pressure potential becomes more negative

  4. less negative because the pressure potential becomes more positive
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When a plant cell is placed in deionised water, water enters by osmosis, increasing turgor pressure. The cell wall resists expansion, creating positive pressure potential. Osmotic potential becomes slightly more negative due to dilution. The net water potential becomes less negative because the positive pressure potential increase outweighs the osmotic change. This is the classic turgor pressure development in plant cells.

Multiple choice

How does a plant accumulate ions from the soil, which has a lower concentration than that in the plant?

  1. It applies pressure to push ions outside the cell.

  2. It applies pressure to push ions into the cell.

  3. It expends energy to transport ions against the concentration gradient.

  4. Its roots grow around soil particles trapping the ions in a cell.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Active transport moves ions from low concentration in soil to high concentration in plant cells, requiring energy expenditure. This is the opposite of passive diffusion which follows concentration gradients. Options A and B incorrectly suggest pressure mechanisms, while D describes a physical trapping process unrelated to ion uptake.

Multiple choice

Nitrogen is utilized by plants for

  1. reproduction

  2. photosynthesis

  3. transpiration

  4. growth & development

  5. excretion
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Nitrogen is utilized by plants for protein synthesis, which is essential for growth and development of the plants.

Multiple choice

Which of the following statements is/are correct?

a. All the gaseous exchange takes place in leaves through stomata for the purpose of photosynthesis. b. The plant closes the stomata when it does not need carbon dioxide for photosynthesis as large amount of oxygen is lost through them. c. The opening and closing of stomatal pore is a function of guard cells.

  1. only a

  2. only b

  3. only c

  4. a and b

  5. a, b and c
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the correct answer. The opening and closing of stomatal pore is a function of guard cells.

Multiple choice

Which of the following statements is/are correct?

a. Xylem vessel is a non-living tube which runs like a drainpipe through the plant. b. Tracheids are long, thin, spindle-shaped cells which are the only water-conducting tissues in all plants. c. Xylem translocates food and hormones in plants.

  1. a only

  2. b only

  3. c only

  4. a and b

  5. a, b and c
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct answer. Xylem vessel is a non-living tube which runs like a drainpipe through the plant.