Biology

Plant Transport and Physiology

1,834 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

How do plants get energy?

  1. From water in their roots

  2. From using sunlight to make food

  3. From absorbing minerals

  4. From breaking down food from other organisms
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Plants are autotrophs that use photosynthesis to convert sunlight, water, and carbon dioxide into glucose, which provides them with energy.

Multiple choice need of water transport in plants biology

Choose the wrongly matched pair w.r.t. pathway of water absorption.


Apoplast pathway Symplast pathway
$(1)$ Involves intercellular spaces and cell wall Involves interconnected protoplasts
$(2)$ Water movement by cytoplasmic streaming Water movement by mass flow
$(3)$ Fast water movement Slow water movement
$(4)$ Occurs in epidermis and cortex Occurs in endodermis

  1. 1

  2. 2

  3. 3

  4. 4
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Answer is 2.
In symplast - Water movement by cytoplasmic streaming.
In apoplast-Water movement by mass flow. 
Multiple choice need of water transport in plants biology

Select the incorrect statements
(a) Older dying leaves export most of their mineral content to younger leaves
(b) Sulphur and calcium are frequently remobilised from senescing parts
(c) lons are absorbed from the soil by both passive and active transport
(d) A $C _3$ plant loses only half as much water as a $C _4$ plant for the same amount of $CO _2$ fixed

  1. (a), (b) and (c)

  2. Only (a) and (c)

  3. Only (b) and (d)

  4. All except (c)
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice need of water transport in plants biology

Aquaporins are transport channels, which

(I) Are found in both plants and animals
(II) Allow for faster water movement between the cells than osmosis
(III) Allow water molecules to pass during transpiration
(IV) Do not open during drought stress

  1. III and IV

  2. Only II

  3. Only III

  4. I and II
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Aquaporins are integral membrane proteins that form pores in the membrane of biological cells, mainly facilitating transport of water between cells. The cell membranes of a variety of different bacteria, fungi, animal and plant cells contain aquaporins through which water can flow more rapidly into and out of the cells than by diffusing through the phospholipid bilayer.  


so the correct option is " I and II'.

Multiple choice need of water transport in plants biology

In plants water moves from ________________.

  1. Less negative to more negative gradient

  2. More negative to less negative gradient

  3. Similar gradient

  4. Zero gradient
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Water potential moves from a region of higher water potential (less negative) to a region of lower water potential (more negative).

Multiple choice need of water transport in plants biology

Which of the following part of a plant absorbs water from the soil?

  1. Stem

  2. Root hairs

  3. Leaves

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Stems and leaves are a part of the shoot which is present away from the soil .

Root hair are present on the surface of roots which are responsible for the absorption of water and minerals from the soil.
So the correct answer is ' Root hairs'.

Multiple choice need of water transport in plants biology

The movement of water from one cell of the cortex to the adjacent one in roots is due to _________________.

  1. Water potential gradient

  2. Accumulation of inorganic salts in the cells

  3. Accumulation of organic compounds in the cell

  4. Chemical gradient
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Accumulation of solutes in the cells caused the cell to take up water from the surroundings. This is seen when the water is absorbed into the roots from the soil. This is due to the development of chemical gradient (both inorganic and organic solutes may develop a chemical gradient).

When we are considering the movement of water from one cell of the cortex to the adjacent one in the root, it is due to the development of water potential gradient which forces the water to move from one cell to the other.
So the correct answer is ' Water potential gradient'.

Multiple choice need of water transport in plants biology

Water absorption through roots can be increased by keeping the plants

  1. In the shade

  2. In dim light

  3. Under the fan

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Water absorption can be increased by increasing Transpiration which can be increased by

1. Increasing the intensity of light
2. Increasing the wind speed.
Hence if kept under the fan, the water absorption increases.
So the correct answer is 'Under the fan'.

Multiple choice need of water transport in plants biology

The root-hairs are suited for absorbing water from the soil because

  1. Root-hairs have a large surface area

  2. Roots have a semi-permeable membrane

  3. Roots contain a solution of higher concentration than the surrounding water.

  4. All the three
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Root hairs are adapted for water absorption through a large surface area, the presence of a semi-permeable membrane, and a high internal solute concentration that creates an osmotic gradient.

Multiple choice need of water transport in plants biology


The mineral ions absorbed by roots reach the leaves through sieve elements

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sieve elements are used to transport organic compounds made during photosynthesis in plants. Sieve elements are the major conducting cells in the phloem. But sieve elements don't transfer the mineral ions absorbed by roots to the leaves

So the given statement is false

Multiple choice biology the fundamental unit of life introduction to cell what are the living organisms made of organisation of the organism cell membrane and cell wall cell wall cell division in embryo development

Roots will absorb water when external medium will be

  1. Hypotonic

  2. Hypertonic

  3. Isotonic

  4. Concentrated
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Osmosis happens along a concentration gradient. If outside medium is hypotonic, it means that relatively more of water is present outside the cells in the surrounding medium and water will flow inside the root hair cells.

Multiple choice evs seeds and seeds interdependencies among organisms hunting plant interdependence between plants and animals

Mycorrhiza is a symbiotic associated of fungus with root system which helps in
A. absorption of water
B. mineral nutrition
C. translocation
D. gaseous exchange.

  1. Only A

  2. Only B

  3. Both A and B

  4. Both B and C
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The roots of some higher plants are associated with fungal mycelia. Such an association is called mycorrhiza. It represents a mutualistic(symbiotic) association between the root system of higher plants and fundal hyphae. The fungal hyphae form a network around the young root and invade the root cells. The external hyphae greatly increase the surface area for absorption of minerals and water from a much larger volume of soil that perhaps the roots alone cannot do.
So, the correct answer is 'Both A and B'.
Multiple choice senescence senescence and death plant growth plant growth and development biology

During senescence of a plant.

  1. The plant displays sequential senescence of the leave

  2. Metabolites like carbohydrates, proteins etc. Are transported from young leaves to the aging leaves

  3. Metabolites like carbohydrates, proteins etc. Are transported out of the aging leaves to the young leaves

  4. Secondary plant products accumulate in the tissues are organs during aging
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice senescence senescence and death plant growth plant growth and development biology

When a plant undergoes senescence, the nutrients may be ____________.

  1. Accumulated

  2. Bound to cell wall

  3. Translocated

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When a plant part undergoes senescence, nutrient resources(minerals and carbohydrates) shift away or are translocated from the senescened part to other parts. In leaves at the time of senescene we observe loss of chlorophyll, RNA and protein, transport of nutrients and then abscission.