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 evs identifying the plants absorption of water from the soil root system the root system

In Monotropa, the special type of root which absorbs nourishment is the 

  1. Haustoria

  2. Mycorrhizal root

  3. Clinging root

  4. Adventitious root
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  1. Haustoria is the specialized structure present in parasitic  plant or fungus that absorbs water and nutrients. For example, Cuscuta.
  2. Mycorrhizal roots are formed by the symbiotic association of plant roots and fungus and helps in nutrient absorption. For example, Monotropa.
  3. Clinging roots are many short branch like adventitious roots arise from nodes. For example, Piper betel.
  4. Adventitious roots are the roots that develop from any part of plant other than radicle. For example, banyan tree
So the correct option is 'Mycorrhizal root'.

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

The tap root system is composed of 

  1. Fibre like parts in the roots

  2. Main root and lateral roots

  3. Thread like branches attached to the base of stem

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

The taproot is the primary root which develops from the elongation of the radicle of the embryo and persists throughout the life of the plant. It forms lateral or secondary roots which further divided to form tertiary roots.

So, the correct option is 'Main root and lateral roots'

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

Lateral roots originate from

  1. Cortex

  2. Epidermis

  3. Endodermis

  4. Pericycle
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$\to$ Endodermis is followed by one or more layers of pericycle.

$\bullet$ It is believed to represent the outer boundary of the vascular strand.
$\bullet$ The cells of pericycle are their walled an parenchymatous in the young root.
$\bullet$ Pericycle is a very important layer. A part of vascular cambium is formed by pericycle.
$\bullet$ All lateral roots originate from it.
$\bullet$ It is absent in the roots of some aquatic plants and parasites.

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

Which of the following is true?

  1. Stem branches are endegenous

  2. Stem branches develop from pericycle

  3. Root branches are exogenous

  4. Root branches are endogenous
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  • The parts which arise from the cortical region or the cortex are called exogenous in origin.
  • The parts which arise from the pericycle are called endogenous origin.
  • The lateral roots or root branches originate endogenously as they originate from the pericycle.
  • So, the correct answer is 'Root branches are endogenous'
Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Root cap is formed by

  1. Dermatogen

  2. Calyptrogen

  3. Wound cambium

  4. Vascular cambium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A. Dermatogen is the primary meristem that forms the outer most layer of a plant or a plant part and forms the epidermis.

B. Calyptrogen is a specialized layer of rapidly dividing cells present at the root tips which continuously divide to form the root cap is formed. 
C. Wound cambium is formed within a masses of cells (callus) which grow over the injured surface of a wound to heal and repair that part.
D. Vascular cambium is a lateral meristem which develops within the vascular bundles to produce xylem to the inner side and phloem to the outer side and is also called fascicular cambium.
So, the correct answer is 'Calyptrogen'.

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

Root apex has a zone of slow dividing cells in the middle of rapidly dividing cells. It is

  1. Quiescent centre

  2. Sluggish centre

  3. Dormant centre

  4. Non-meristematic zone
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • The root-promeristems that contain the initials of epidermis, cortex and stele is known as Quiescent centre.
  • These cells divide less frequently as they are inactive and are present at the pole of cortex and stele.
  • The cells with QC have small dictyosomes, nuclei and nucleoli with little cytoplasm.
  • These cells also have little endoplasmic reticulum, mitochondria and contain low concentrations of RNA, DNA and protein than the other cells of the root apex.
  • So, the correct answer is 'Quiescent centre'
Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Lateral roots arise from primordia developed by division of

  1. Pericycle cells in between two protoxylem points

  2. Pericycle cells opposite protoxylem points

  3. Endodermis cells in between two protoxylem points

  4. Endodermis opposite protoxylem points
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Lateral roots arise endogenously from other roots and increase the absorptive surface of the plant. Most lateral roots are initiated some distance basipetal to the apical meristem, differentiated cells must become reprogrammed to give rise to the initial divide and enlarge in very precise patterns to organize a new organ recognizable as a root. 

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

Root hair develop from

  1. Zone of cell maturation

  2. Zone of cell elongation

  3. Zone of mature cells

  4. Zone of cell formation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The region of maturation is located at the top of the root, or closest to the plant. The end of the root is known as the root cap. A plant cell will begin in the region of cell division, and then travel to the region of elongation. In this zone, a cell will elongate and then travel to the zone of maturation. Root hair cells are outgrowths at a tip of the plant's roots. They are found only in the zone of maturation, and not the zone of elongation, possibly because any root hairs that arise are sheared off as the root elongates and moves through the soil.

So, the correct answer is 'A'.
Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Quiescent centre occurs in

  1. Shoot apex

  2. Root apex

  3. Both A and B

  4. Meristematic tissue
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The root-promeristems of higher plants have a central part called the quiescent centre.
  • The cells here divide less frequently as they are inactive and are present at the pole of cortex and stele.
  • They may consist of four cells (minimum) or can go up to 600 cells which show very low mitotic activity.
  • In closed meristem, QC is hemispherical in shape whereas, in open meristem it is disc-shaped.
  • The QC is unusual in the centre of shoots.
So, the correct answer is 'Root apex'
Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Quiescent centre is region of root apex which is

  1. Actively dividing

  2. Water absorption area

  3. Inactive cells

  4. Root hair area
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • The quiescent centre is that part of the root-promeristems that contains the initials of epidermis, cortex and stele.
  • These cells divide less frequently as they are inactive and are present at the pole of cortex and stele.
  • The cells with QC have small dictyosomes, nuclei and nucleoli. 
  • These cells also have little endoplasmic reticulum, mitochondria and contain low concentrations of RNA, DNA and protein than the other cells of the root apex.
So, the correct answer is 'Inactive cells'
Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Calyptrogen gives rise to

  1. Root

  2. Root cap

  3. Plerome

  4. Periblem
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The root apical meristem gives rise to three primary meristems- procambium, ground meristem, protoderm and the root cap
  • Calyptrogen is a specialized internal meristematic cell derived from the root apical meristem
  • They divide internally to produce a protective cap-like structure at the root tip called the root cap
  • The root cap is also known as calyptra
So, the correct answer is 'Root cap'
Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Rootlets are called as

  1. Tap root

  2. Adventitious roots

  3. Lateral roots

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

Rootlets are also called as lateral root and are defined as the small branches of roots that form from the main root and helps the plant for the absorption of water and minerals as they increase surface area.

So, the correct option is 'Lateral roots'.

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

In the transverse section of a dicot root.

  1. The protoxylem vessels are present towards the periphery and metaxylem vessels are present towards the centre

  2. The protoxylem vessels are present towards the centre and metaxylem vessels are present towards the periphery

  3. Protoxylem is completely surrounded by the metaxylem vessels

  4. Metaxylem is completely surrounded by protoxylem
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In dicot roots, the xylem arrangement is exarch, meaning the protoxylem is located towards the periphery and the metaxylem is towards the center.