Biology Multiple Choice Questions on “Transportation in Plants”.
1. Vascular bundle is composed of _________
a) xylem
b) phloem
c) both xylem and phloem
d) cambium
Answer: c
Clarification: Vascular bundle is mainly composed of xylem and phloem. There is presence of intra-vascular cambium and inter-vascular cambium in between them in different stages of their life cycle.
2. Which kind of transport is present in xylem?
a) No transport
b) Unidirectional
c) Bidirectional
d) Multidirectional
Answer: b
Clarification: Xylem transports water and minerals in a particular direction from roots to leaves via stem. The movement of phloem is usually bidirectional and sometimes multidirectional.
3. Cytoplasmic streaming is a form of active transport for short distances.
a) True
b) False
Answer: a
Clarification: Cytoplasmic streaming aids active transport of substances for short distances. It is a type of symplastic movement and observed in cells of Hydrilla and Tradescantia.
4. Mineral Nutrients are taken up by ________
a) leaves
b) stems
c) branches
d) roots
Answer: d
Clarification: Mineral nutrients are taken up by roots from the soil. It is then passed to the leaves via stem the sink organs such as branches, fruit, seed, embryo etc.
5. Minerals are re-exported by __________
a) leaves
b) stems
c) branches
d) roots
Answer: a
Clarification: Minerals are obtained from the soil by the roots reach the leaves. From the leaves, they are then distributed to different sinks as per requirement of the organs.
6. Who is the Father of Plant Physiology?
a) Stephan Hales
b) Schwendener
c) Melvin Calvin
d) Lipmann
Answer: c
Clarification: Stephan Hales is the Father of Plant Physiology. Schwendener was the first to propose stomatal movements are due to turgor changes in the guard cells. Melvin Calvin received Nobel Prize in 1961 for mapping the pathway of carbon assimilation in photosynthesis. Lipmann is known as the father of ATP Cycle.
7. The theory proposed to explain the mechanism of stomatal movement?
a) The starch-sugar interconversion theory
b) Theory of photosynthesis in guard cell
c) Theory of glycolate metabolism
d) Active potassium transport ion concept
Answer: a
Clarification: Steward in 1964 proposed a modified scheme of inter-conversion of starch and sugar for stomatal movement. Theory of photosynthesis in guard cells was given by Von Mohl in 1856 and proposed that chloroplasts in the guard cells photosynthesize leading to production of sugar. Theory of glycolate metabolism was given by Zelitch in 1963 and he proposed that production of glycolic acid in the guard cells is a necessary factor in stomatal opening. Active Potassium Pump theory was given by Fujino. Levitt & Rashke in 1975 supported the theory of the K+ ion transport active mechanism requires ATP.
8. Plants lose water mainly by the process of _____
a) Guttation
b) Exudation
c) Transpiration
d) Evaporation
Answer: c
Clarification: Transpiration is the major cause of water loss in plants. Evaporation is the second main reason while guttation and exudation are removal of extra water from the plant.
9. Root system in a plant develops well when __________
a) deficiency of copper
b) absorption of water increases
c) deficiency of auxin
d) deficiency of ABA
Answer: b
Clarification: Root system in a plant develops well when absorption of water increases. Deficiency of copper of leads to necrosis. Deficiency of auxin leads to excess differentiation of xylem. Deficiency of ABA leads to non-closure of stomata even during water stress conditions.
10. Water entering roots through diffusion is a ____________
a) endosmosis
b) osmosis
c) passive absorption
d) active absorption
Answer: c
Clarification: Water entering roots through diffusion is a passive absorption. Osmosis requires a presence of semi-permeable membrane which is absent in case of roots and soil. Endosmosis is the process of entry of water inside the guard cells when the DPD inside the cell is higher than the surrounding medium.