Biology · Science General

Botany and Plant Science

4,989 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 stem internal structure of monocots internal structure of stem(dicot and monocot)

The lacunae in the vascular bundles of monocot stem is

  1. A mucilage canal

  2. Protoxylem lacuna

  3. Lysigenous cavity

  4. Both B and C
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The first xylem formed is called as protoxylem. Protoxylem is later torn apart and a cavity is formed. The entire protoxylem is dissolved hence, such cavity is called as lysigenous cavity. The protoxylem shows an empty space, called as 'lacuna'. 

This type of intercellular space arises through dissolution of entire cells, which are therefore called as lysigenous intercellular spaces. These cavities of intercellular spaces store up water, gases and essential oils in them. The examples are commonly found in water plants and many monocotyledonous plants.

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

Transverse section of a material exhibits conjoint collateral endarch and closed bundles scattered in a ground tissue, what should be the material?

  1. Monocot root

  2. Dicot root

  3. Monocot stem

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

Monocot stem vascular bundles are found irregularly scattered in the ground tissue. 

Towards the periphery, the bundles are smaller in size while towards the centre, they are larger in size. The smaller bundles are younger, while the larger ones are older. Hence, the arrangement is described as endarch. 
Each vascular bundle has a covering called bundle sheath formed by a single layer of sclerenchyma cells. The vascular bundle encloses both xylem and phloem. Xylem is found towards the inner surface and phloem towards the outer surface. Cambium is absent. Hence the vascular bundles are described as conjoint, collateral and closed. 
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, open and tetrarch. There are four bundles each of xylem and phloem occurring alternately. Xylem is described as exarch. 
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. 

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

T.S. of a material exhibits conjoint collateral endarch and closed bundles scattered in a ground tissue. What should be the material?

  1. Monocot root

  2. Dicot root

  3. Monocot stem

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

Monocot stem vascular bundles are found irregularly scattered in the ground tissue. Towards the periphery, the bundles are smaller in size while towards the centre, they are larger in size. The smaller bundles are younger, while the larger ones are older. Hence, the arrangement is described as endarch. 

Each vascular bundle has a covering called bundle sheath formed by a single layer of sclerenchyma cells. The vascular bundle encloses both xylem and phloem. Xylem is found towards the inner surface and phloem towards the outer surface. Cambium is absent. Hence the vascular bundles are described as conjoint, collateral and closed. 
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, open and tetrarch. There are four bundles each of xylem and phloem occurring alternately. Xylem is described as exarch. 
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. 

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

Atactostele is found in

  1. Dicot stem

  2. Monocot stem

  3. Dicot root

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

Monocot stems, in which the stele consists of many vascular bundles in a complex arrangement, are said to have an atactostele. 

Atacostele is atype of eustele, found in monocots, in which the vascular tissue in the stem exists as scattered bundles. Thus, option B is correct. 

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

Stem of date palm increases in girth due to activity of:

  1. Intercalary meristem

  2. Apical meristem

  3. Lateral meristem

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

Date palm is a monocot and lack lateral meristem; the meristem present along the sides causing the increase in girth of the plant. 

Apical meristem is present at the tips of root and shoot and give rise to primary permanent tissue systems. The apical meristem causes increase in height of the date palm from growing tips. The apical meristem is modified to form temporary meristem which serves the function of lateral meristem, divide and produce new cells. Enlargement of these peripheral cells cause increase in girth of the date palm. 
The apical meristem, which is separated from apices due to formation of permanent tissues in between, is termed as intercalary meristem; it is internodal in position and carries out localized growth. 
Thus, the correct answer is option (B).

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

Lysigenous cavity and 'Y'-shaped xylem occurs in

  1. Dicot stem

  2. Monocot root

  3. Monocot stem

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

Lysigenous intercellular spaces is type of intercellular space arises through dissolution of entire cells, which are therefore called as lysigenous cavity. These cavities of intercellular spaces store up water, gases and essential oils in them. The examples are commonly found in water plants and many monocotyledonous stems. The secretory cavities in Eucalyptus, Citrus and Gossypium are good examples. In monocot stem the vascular bundle encloses both xylem and phloem. Xylem is found towards the inner surface and phloem towards the outer surface. Cambium is absent. Hence, the vascular bundles are described as conjoint, collateral and closed. In the xylem, there are two metaxylem and two protoxylem vessels arranged in the shape of Y. 

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

Endodermis is not differentiated in which of the following 

  1. Monocot root

  2. Dicot root

  3. Monocot stem

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

In monocot stem, cortex is not differentiated into hypodermis, general cortex and endodermis. In the place of cortex a large, wide region is present called Ground tissue is present. It is parenchymatous, stores water and food materials. In this vascular bundles are present scatteredly.

So, the correct option is ‘monocot stem’

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

Fibrovascular bundles or vascular bundles covered by sclerenchymatous sheath are found in

  1. Monocot leaf

  2. Monoct stem

  3. Monocot root

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

A.Monocot leaf – vascular bundles are covered by parenchymatous bundle sheath.

B. Monocot stem – vascular bundles are covered by sclerenchymatous fibres. So these are called fibrovascular bundles.

C. Monocot root – there is no any covering around the vascular bundles.

D. Dicot stem – there is no any covering around the vascular bundles.

So, the correct option is ‘Monocot stem’.

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

Phloem parenchyma is absent in

  1. Dicot root

  2. Dicot leaf

  3. Monocot stem

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

A.Dicot root – phloem parenchyma is present.

B.Dicot leaf – Phloem parenchyma is present.

C.Monocot stem – phloem parenchyma is absent.

D.Dicot stem – Phloem parenchyma is present.

So, the correct answer is 'Monocot stem'.

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

A T.S. shows conjoint, collateral, endarch and closed bundles scattered in a ground tissue. It is?

  1. Dicot stem

  2. Monocot stem

  3. Dicot root

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

A.Dicot stem – collateral, conjoint, endarch, open vascular bundles present in the form of rings.

B.Monocot stem – collateral, cojoint, endarch, closed vascular bundles present in the form of scattered manner in a ground tissue.

C.Dicot root – radial vascular bundles are present.

D.Monocot root – radial vascular bundles are present.

So, the correct option is ‘Monocot stem’.

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

Which of these characters does$/$ do not apply to vascular bundle of monocot stem?
I. Conjoint
II. Endarch protoxylem
III. Open
IV. Phloem parenchyma is absent.

  1. I and II only

  2. II and III

  3. III and IV

  4. III

  5. I and IV only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

I.Conjoint – applicable – because xylem and phloem are present side by side in the vascular bundles.

II.Endarch protoxylem – applicable – because protoxylem is present towards medulla side and metaxylem is present towards the pericycle side.

III.Open – not applicable – because, cambium is absent between the xylem and phloem in the vascular bundles.

IV.Phloem parenchyma is absent – applicable – in the phloem of monocots phloem parenchyma is not present.

So, the correct option is ‘III’

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

Monocot stem has

  1. Bicollateral closed vascular bundles

  2. Bicollateral open vascular bundles

  3. Collateral open vascular bundles

  4. Collateral closed vascular bundles
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A.Bicollateral closed vascular bundles – Not present in any plants

B.Bicollateral open vascular bundles – found in the stems of Cucurbitaceae members

C.Collateral open vascular bundles – found in the dicotyledonous stems.

D.Collateral closed vascular bundles – found in the monocotyledonous stems.

So, the correct option is ‘Collateral closed vascular bundles’.

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

A structure absent in monocot is

  1. Sieve tubes

  2. Stomata

  3. Cambium

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

In monocot stem, epidermis, hypodermis, ground tissue, and vascular bundles are present. General cortex, endodermis, pericycle, medulla, medullary are absent. In the phloem, phloem parenchyma is also absent. Xylem and phloem are present on same radii, and also present side by side. So they are also called Collateral and Conjoint vascular bundles. In the vascular bundles, cambium is absent between xylem and phloem, So these are closed vascular bundles. In the xylem, protoxylem is towards the centre, and metaxylem is towards the periphery. So, it is an endarch xylem. 

So, the correct option is 'Pith or cambium'.

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

Which one is false about monocot stem?
I. Vascular bundles is scattered, cojoint, close, surrounded by sclerenchymatous bundle sheath and cavity.
II. Hypodermis is scelerenchymatous.
III. Peripheral vascular bundles is smaller than centrally placed ones.
IV. Ground tissue is differentiated into cortex, pericycle, pith, etc.
V. Homogeneous parenchymatous ground.

  1. I, III, IV

  2. III, IV

  3. IV

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

The monocot stem shows the following characteristics: 

I. Vascular bundles are scattered in the ground tissue, conjoint, collateral and they are surrounded by the sclerenchymatous layer of bundle sheath. They have a lysigenous cavity formed by the breakdown of inner protoxylem vessels and parenchyma.
II. The hypodermis is made up of sclerenchymatous cells.
III. The peripheral vascular bundles are smaller in size and are more than the central vascular bundles.
IV. Ground tissue is not differentiated into cortex, pericycle, pith etc.
V. Ground tissue is homogeneous and is made of parenchymatous cells.
Hence, the correct answer is 'Ground tissue is differentiated into cortex, pericycle, pith etc.'