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 botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Read the following statements :
(i). In monocot root, a large number of vascular bundles are arranged in the form of a ______ around the central ____
(ii). Due to the presence of _, the endodermal cells do not allow wall to wall movement of substances between cortex and pericycle, in a primary dicot root.
(iii). The epidermis of stem of sunflower bears several unbranched _____ hair.
(iv). The central portion of a dicot stem is usually occupied by ______ comprising of thin-walled parenchymatous cells
Select the option that correctly fills the blanks in any two of them.

  1. (i) ring, pith; (ii) hypodermis

  2. (ii) Casparian strips; (iii) unicellular

  3. (i) ring, cortex; (iv) vascular bundles

  4. (iii) multicellular; (iv) pith
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Statement (iii) is correct as sunflower stems have multicellular hairs (trichomes). Statement (iv) is correct as the central portion of a dicot stem is the pith. The other statements contain errors regarding the arrangement or terminology.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root
Well developed pith is found in

  1. Monocot root and monocot stem

  2. Monocot stem and dicot root

  3. Monocot root and dicot stem

  4. Dicot root and dicot stem
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Well developed pith or parenchymatous central region is present in monocot root (maize) and dicot stem (Sunflower). Its a structure of loosely arrannged cells that embeds vascular tissue, it may store food.

So, the correct answer is 'Monocot root and dicot stem'

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Polyarch condition is found in

  1. Monocot root

  2. Dicot root

  3. Monocot stem

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

Monocot root vascular bundles are radial in arrangement. There are eight bundles each of xylem and phloem. Hence, the condition is described as polyarch. Xylem is described as exarch in monocot root. 

Monocot stem vascular bundles are conjoint, collateral and closed with endarch xylem. 
Dicot root vascular bundles are described as radial and tetrarch. There are four bundles each of xylem and phloem occurring alternately. Xylem is described as exarch. 
Dicot stem vascular bundles are eight in number, arranged in form of a broken ring. The vascular bundles are conjoint, collateral and open. Xylem is on the inner surface and phloem on the outer surface. Xylem is described as endarch. 

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Passage cells are more distinct in endodermis of

  1. Dicot stem

  2. Monocot stem

  3. Dicot root

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

Passage cells are endodermal cells of older roots, which have retained thin walls and Casparian strips rather than becoming suberized and waterproof like the other cells around them, to continue to allow some symplastic flow to the inside. 

Passage cells function to allow transfer of solutes, such as calcium and magnesium into the stele, in order to eventually reach the transpiration system.
Passage cells are more distinct in endodermis of monocot root and absent in dicot root, monocot stem and dicot stem. Thus, option D is correct.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Polyarch and exarch condition of found in

  1. Monocot stem

  2. Monocot root

  3. Dicot stem

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

Monocot root vascular bundles are radial in arrangement. There are eight bundles each of xylem and phloem. Hence, the condition is described as polyarch. Xylem is described as exarch. 

Monocot stem vascular bundles are numerous in number and the xylem is endarch. 
Dicot stem vascular bundles  are eight in number, arranged in form of a broken ring. The vascular bundles are conjoint, collateral and open. Xylem is on the inner surface and phloem on the outer surface. Xylem is described as endarch. 
Dicot root vascular bundles are described as radial and tetrarch. There are four bundles each of xylem and phloem occurring alternately. Xylem is described as exarch. 

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Eustele is characteristic of

  1. Monocots

  2. Dicots

  3. Pteridophytes

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

Eustele - In this arrangement, the primary vascular tissue consists of vascular bundles, usually in one or two rings around the pith. In addition to being found in stems, the eustele appears in the roots of monocot flowering plants. The vascular bundles in a eustele can be collateral with the phloem on only one side of the xylem or bicollateral with phloem on both sides of the xylem, as in some Solanaceae. So, eustele is the characteristic of monocots and absent in dicots, pteridophytes and bryophytes. 
Thus, the correct answer is option A.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Two cross-sections of stem and root appear similar, when viewed by naked eye. But under microscope, they can be differentiated by

  1. Exarch condition of root and stem

  2. Endarch condition of stem and root

  3. Endarch condition of root and exarch condition stem

  4. Endarch condition of stem and exarch condition of root
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Endarch is the arrangement in which the protoxylem is directed towards the centre and metaxylem elements towards the periphery. The development of the xylems in this arrangement follows the centrifugal pattern. It is the characteristics of the stem of flowering plants. 

Whereas exarch is the arrangement in which the protoxylem is directed towards the periphery and metaxylem towards the centre. The development of the xylem in this arrangement follows the centripetal pattern. It is the characteristics of roots. Thus, option D is correct.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Polyarch and exarch condition is found in

  1. Monocot stem

  2. Monocot root

  3. Dicot stem

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

Monocot root vascular bundles are radial in the arrangement. There are eight types of bundles each of xylem and phloem. Thus the condition is described as the polyarch. Xylem is detailed as an exarch.

Monocot stem vascular bundles are many in number and the xylem is the endarch.

Dicot stem vascular bundles are also eight in number but arranged in the form of a broken ring. The vascular bundles are conjoint, collateral and open. Xylem is on the inner surface and phloem on the outer surface. Xylem is described as an endarch.

Dicot root vascular bundles are described as radial and tetrarch. There are four bundles each of xylem and phloem occurring alternately. Xylem is described as an exarch.

So, the correct answer is 'Monocot root'

So, the correct answer is B.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

In roots, lateral branches grow from.

  1. Epiblema

  2. Pericycle

  3. Cortex

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

A. Epiblema – root epidermis with root hairs is called epiblema

B. Pericycle – outer most part of the stele in roots and dicot stem, produces lateral branches

C. Cortex – middle of root and dicot stem internally

D. Endodermis – inner most part of the cortex

So, the correct option is ‘Pericycle'

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Passage cells occur in

  1. Monocot root

  2. Dicot root

  3. Monocot stem

  4. Aerial root
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

Endodermal cells without casparian strips or bands are called passage cells. These are present opposite to the protoxylem cells. These are found in both dicot root and monocot root.

So, the correct option is 'Monocot root & dicot root'.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

As compared to a dicot root, a monocot root has

  1. More abundant secondary xylem

  2. Many xylem bundles

  3. Inconspicuous annual rings

  4. Relatively thicker periderm
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The anatomy of dicot root differs from monocot root, in activity of pericycle, no. of xylem strands, presence of medulla, activity of conjunctive tissue.  

In dicot root, pericycle is involved in the formation of lateral roots and vascular cambiu, where as in monocot root, pericycle is involved in the formation of lateral roots. 
In dicot root 2 to 4 xylem strands are present in the stele, where as monocot root more than 4 xylem strands are present.
In dicot root, medulla is reduced, where as in monocot root medulla is well developed.
In dicot root, conjunctive tissue involved in the formation of vascular cambium, where as in monocot root, it is not involved in the formation of vascular cambium.
So, the correct option is 'Many xylem bundles'.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Out of the following, how many features belong to monocot root? 
1. Radial vascular bundles 
2. Closed vascular bundles
3. Endodermis absent
4. Pith developed
5. Polyarch condition

  1. One

  2. Two

  3. Three

  4. Four
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
When xylem and phloem within a vascular bundle are arranged in an alternate manner on different radii, then it is called Radial vascular bundles. It is true for monocot roots.
When there is no cambium present between the xylem and phloem elements, the bindle is said to be Closed vascular bundles.It is true for monocot roots.
Endodermis is very distinct in monocot root.Hence, sentence number 3 does not belong to the features of monocot root.
Pith is large and well developed in roots of monocotyledonous plants.
Monocot root comprises of more than six xylem bundles i.e. Polyarch condition.
So, the correct option is 'Four'
Multiple choice botany internal structure of root, stem and leaf internal structure of monocot root internal structure of root(dicot and monocot) anatomy of root

Which of the following is seen in a monocot root?

  1. Large pith

  2. Vascular cambium

  3. Endarch xylem

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

In monocot root, the vascular bundles are usually more than six in number. Pith is large and parenchymatous. The parenchyma of the pith become lignified and sclerenchymatous.

Multiple choice biology transport in plants diffusion transport in vascular plants types of transport

Which region of plants is considered as supply end?

  1. Root

  2. Fruit

  3. Leaf

  4. Flower
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The translocation of sugars in a plant occurs from source to sink by active loading at source or supply end and active unloading at the sink end. The source and sink are not fixed and keep on changing depending on the physiology of plant. In water transport water is always transported from roots to the aerial parts but not so in case of sugars. 

Sugars are transported from a region, where they are present in high concentration, example leaves to regions of sugar utilisation or storage parts, example storage roots or tubers or fruits etc. 
Thus, storage organs like tubers, roots, fruits etc. serve as sink end and leaves acts as supply end.