Biology · Science General

Botany and Plant Science

5,038 Questions

Botany and plant science delve into the biological study of plant life, covering structural anatomy, physiological processes, and reproductive mechanisms. Key topics include inflorescence patterns, root modifications, and seed development, which are vital for biology sections in medical entrance exams. This collection of practice questions helps solidify understanding of complex plant functions.

Plant ReproductionPlant AnatomyRoot ModificationsInflorescence PatternsPlant Morphology

Botany and Plant Science Questions

Multiple choice biology movement and locomotion in living organisms movements in plants coordination in plants tropic and nastic movements in plants

Sensation of phototropism is perceived by

  1. Root tip

  2. Shoot tip

  3. Axillary bud

  4. Node
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The area of the plant which perceives a stimulus is called as perceptive region. Tip of the shoot is the perceptive region for the sensation of phototropism. The area of the plant which shows the response is called as responsive region. 
Thus, the correct answer is option B.
Multiple choice biology movement and locomotion in living organisms movements in plants coordination in plants tropic and nastic movements in plants

Tendrils exhibit/twining of tendrils is due to

  1. Thigmotropism

  2. Seismonasty

  3. Heliotropism

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

The movement of plant part in response to contact with a solid touch is called as thigmotropism. The twining movements due to support seen in tendrils and twiners is an example of thigmotropism. Seismonasty is the nastic response of a plant to touch or vibration. Dropping of leaves of Mimosa pudica upon touching is due to seismonasty. Heliotropism is a growth movement or bending of stem in the direction of the light. It is also called as solar tracking. Diageotropism is plant part response to the gravity such that it grows horizontal to the gravity.

Thus, the correct answer is option A.

Multiple choice biology movement and locomotion in living organisms movements in plants coordination in plants tropic and nastic movements in plants

Stems are positively geotropic while roots are negatively geotropic.

  1. True

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

Geotropism means growth in response to the gravitational force. Stems grow away from ground (ie in opposite direction in which the gravitational force is exerted), while roots grow toward the ground. Therefore, stems are negatively geotropic, which roots are positively geotropic.

Multiple choice biology movement and locomotion in living organisms movements in plants coordination in plants tropic and nastic movements in plants

Movements in Mimosa pudica are due to turgor changes in

  1. Pulvinus and pulvinnules

  2. Pinna and pinnules

  3. Leaf and leaflets

  4. Petiole and rachis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Turgor movement is a reversible change in position of a plant part due to a change in turgidity of cells. It is mostly caused by contact. Mimosa pudica shows dropping of leaves upon touching. In this sensitive plant, the pulvinus and pulvinnules are responsible for the folding of the leaves. In this, turgor changes occur in thin walled cells of pulvinus present on lower side and pulvinnules present on upper side. This results in folding of pinnules and pinnae comes together causing drooping of the compound leaves.

Thus, the correct answer is option A.

Multiple choice biology identifying the plants absorption of water from the soil root system the root system

Primary roots and its branches constitutes to

  1. Adventitious root system

  2. Tap root system

  3. Fibrous roots

  4. Seminal roots
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A. Adventitious roots are the roots which are produced from other plant parts like stems, leaves etc.

B. Taproot system is the root system where the root develops from the radicle producing primary roots and its branches secondary roots. Here the radicle persists.
C. Fibrous roots are the roots which are short and appear as a bunch when the radicle is absent.
D. Seminal roots are temporary roots which are present during ungerminated caryopsis.
So, the correct answer is 'Tap root system'.

Multiple choice movement in plants living world of plants - plant physiology biology

Some flowers (e.g., Oxalis) open in the morning and close during evening.

because of

  1. Photonasty

  2. Phototropism

  3. Phototaxis

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

Photonasty - the tendency in certain plant species to respond to light by developing sufficient cellular force or growth on one side of an axis to change the form or position of the axis, as in the opening and closing of the flowers of four-o'-clocks.

Multiple choice movement in plants living world of plants - plant physiology biology

Desmodium gyrans shows movement of leaflets. This type of movement

is 

  1. Nastic movement

  2. Curvature movement

  3. Movement of variation

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

Desmodium gyrans is also called as 'Indian telegraph plant' which is a dancing plant. The movement in this plant is called as movement of variation. It is not categorized into nastic or curvature movements.

Multiple choice movement in plants living world of plants - plant physiology biology

Opening of a flower and drooping of a bud are examples of

  1. Nyctinasty

  2. Hypnoasty

  3. Seismonasty

  4. Moment of curvature
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

If the movement of curvature exhibited by plant organs is due to some external stimuli (caused by light, temperature, gravity, foreign bodies, etc), it is called induced movement of curvature. There are several spontaneous movements of curvature like Nastic movements, nutation, etc. Opening of sunflower is due to the light radiation of the sun. So it is an example of photonastic movement. Seismonasty is induced by movement by touch, shock, rain, wind, etc. Example: the leaves of plants Mimosa pudica and M.spegazzinii. All these are included in movement of curvature.

Multiple choice movement in plants living world of plants - plant physiology biology

Opening of floral buds into flowers is a type of 

  1. Autonomic movement of variation

  2. Paratonic movement of growth

  3. Autonomic movement of growth

  4. Autonomic movement of locomotion
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Growth movements are brought about by the unequal growth in different regions of the same organ. If shoot growth occurs at a faster rate alternately on right and left sides of the axis, resulting in a zig-zag axis, the movement is said to be nutation. When the leaves mature in growth and the flower buds open, more rapid growth occurs on the upper surface. This results in unfolding of coiled leaves and opening of the flowers. These are categorised under autonomic movement of growth.

Multiple choice movement in plants living world of plants - plant physiology biology

Circinate vernation in leaves is caused due to

  1. Epinasty

  2. Hyponasty

  3. Apostrophe

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

Vernation is the formation of new leaves or fronds. Circinate vernation is the manner in which a fern frond emerges. As the fern frond is formed, it is tightly curled so that the tender growing tip of the frond is protected within a coil. At this stage it is called a crozier or fiddlehead. As the lower parts of  the frond expand and toughen up, they begin to photosynthesize, supporting the further growth and expansion of the frond. In case of many fronds, long hairs or scales provide additional protection to the growing tips before they are fully uncoiled. Circinate vernation may also be observed in the extension of leaflets, in the compound leaves of Cycads.