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 dicot stem internal structure of stem(dicot and monocot) anatomy of stem

Fascicular cambium is the cambium of vascular bundle of

  1. Monocot stem

  2. Dicot stem

  3. Monocot leaf

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

Intrafascicular cambium is present between xylem and phloem in dicot stem. It is also termed as fascicular cambium. This meristematic area spreads laterally from each bundle and eventually becomes continuous, forming a complete vascular cambium.

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

Two cross-sections of stem and root appear simple, 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 of 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.

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

In dicot stems, vascular cambium is formed from ________.

  1. Procambium

  2. Cambium

  3. Promeristem

  4. Protoderm
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • The vascular cambium makes up the growth layer in the stems and roots of many plants (in dicots- buttercups etc) 
  • They are unspecialized cylindrical meristematic cells that divide to form secondary vascular tissues.
  • The vascular cambium is derived from the procambium which is present in the vascular bundles and the interfascicular parenchyma cells which are present between the vascular bundles
  • So, the correct answer is 'Procambium'
Multiple choice botany internal structure of root, stem and leaf internal structure of dicot stem internal structure of stem(dicot and monocot) anatomy of stem

Oldest part of phloem in a dicot stem is situated just.

  1. Outside vascular cambium

  2. Inner to primary cortex

  3. Inner to vascular cambium

  4. Between periderm and primary cortex
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In dicot stem during secondary growth, the oldest part of xylem situated towards outer to the medulla and oldest phloem is situated just towards inner to the primary cortex.

So, the correct option is ‘Inner to primary cortex’.

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

The endarch condition is characteristic of

  1. Root

  2. Stem

  3. Leaves

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

A. Root – protoxylem is towards the pericycle and metaxylem is towards the medulla. It is called Exarch.

B. Stem – protoxylem is towards the medulla and metaxylem is towards the pericycle. It is called Endarch.

C. Leaves – the position of protoxylem and metaxylem is not specified.

D. Petiole – the position of protoxylem and metaxylem is not specified.

So, the correct option is ‘stem’.

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

In dicot stem, the pericycle is?

  1. Single layered

  2. Multilayered

  3. Two layered

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

Pericycle is the outer most part of the stele. In dicot, stem pericycle is, sclerenchymatous, discontinuous, multilayered and present in the form of patches over the vascular bundles.

So, the correct option is ‘Multilayered’.

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

A T.S. of dicot stem shows

  1. Vascular bundles arranged in a ring

  2. Scattered vascular bundles

  3. Closed vascular bundles

  4. Radial vascular bundles
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A.Vascular bundles arranged in a ring – found in T.s. of dicot stem

B.Scattered vascular bundles – found in T.s.of monocot stem

C.Closed vascular bundles – found in T.s.of monocot stem

D.Radial vascular bundles – found in T.s.of dicot and monocot roots.

So, the correct option is ‘Vascular bundles arranged in a ring’.

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

Inner-most layer of cortex is

  1. Pericycle

  2. Endodermis

  3. Cutinised

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

A.Pericycle – outer most part of the stele in roots and dicot stem.

B.Endodermis – innermost part of cortex in roots and dicot stem.

C. Cutinised – The outer walls of stem epidermal cells are cutinized i.e.covered by the cuticle.

D.Suberised – The walls of cork cells are suberized i.e. made up of suberin.

So, the correct option is ‘Endodermis’.

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

Common features between lenticels and hydathodes are

  1. Allow exchange of gases

  2. Always remain closed

  3. There is no regulation of their opening and closing

  4. They occur on the same organ of the plant
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The large sized, slightly raised spots present on the surface of cork, in old dicot stems are called Lenticels. These are involved in the exchange of gases.

The small pores, present on the epidermis of grass leaves are called Hydathodes. In this guard cells are immovable. They perform guttation.

So, the correct option is ‘There is no regulation of their opening and closing’.

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

Fascicular cambium of dicot stems is?

  1. Apical meristem

  2. Primary meristem

  3. Secondary meristem

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

A.Apical meristem – meristem present in the apices of plant parts, found in all higher plants.

B.Primary meristem – meristem formed from embryonic tissues or promeristem. eg:Fascicular cambium – found in dicotyledons

C.Secondary meristem – meristem formed by the dedifferentiation of permanent tissues. eg:Inter fascicular cambium, cork cambium- found in dicotyledons

D.Intercalary meristem – meristem present in between permanent tissues, found in monocotyledons

So, the correct option is ‘Primary meristem’.     

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

A narrow layer of thin-walled cells found between phloem$/$ bark and wood of a dicot is?

  1. Cork cambium

  2. Vascular cambium

  3. Endodermis

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

In dicotyledonous stems of temperate trees, during secondary growth, vascular cambial ring(narrow layer of thin-walled cells) produces secondary phloem towards outer side and secondary xylem or wood towards inner side.

So, the correct option is ‘vascular cambium’.

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

In dicot stem, xylem is

  1. Polyarch

  2. Monoarch

  3. Endarch

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

A.Polyarch – stele with many xylem strands, is found in monocot roots.

B.Monoarch – stele with one xylem strand, is found in Trapa.

C.Endarch – protoxylem is present towards the centre, and metaxylem is present towards the periphery, is found in dicot and monocot stems.

D.Exarch – protoxylem is towards the periphery, metaxylem is towards the centre, is found in dicot and monocot roots.

So, the correct option is ‘Endarch’.

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

Laticiferous glands occur in plant part

  1. Cortex

  2. Vascular bundle

  3. Epidermis

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

Latex is a milky white secretory material. It is secreted by a special tissue  called are Laticiferous tissues. These are found in the plants growing in tropical deciduous forests. These are present in two types, namely latex cells and latex vessels. Latex is used in the manufacture of rubber. In the plants

laticiferous glands are connected to cortex. 
So, the correct option is 'Cortex'.

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

Inner darker, harder portion of secondary xylem that cannot conduct water in older dicot stem is called?

  1. Alburnum

  2. Bast

  3. Duramen

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

A-The outer light coloured, functional secondary xylem or wood, takes up in the conduction of water of sap is called sapwood or alburnum.

B.Bast - secondary phloem formed during secondary growth from vascular cambium towards its outer side.
C. Duramen - The central or inner dark coloured non-functional wood or secondary xylem, not takes part in the conduction of water is called Duramen or Heartwood.
D.Wood - secondary xylem formed during secondary growth from vascular cambium towards its inner side.

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

You are given a fairly old piece of dicot stem and a dicot root. Which of the following anatomical structures will you use to distinguish between the two.

  1. Secondary phloem

  2. Protoxylem

  3. Cortical cells

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

The anatomy of dicot root and dicot stem differ in many characters. In dicot, root epidermis contains root hairs, whereas in epidermis contains trichomes, cuticle and stomata. In dicot, root cortex shows general cortex and endodermis, whereas in dicot stem cortex shows hypodermis, general cortex and endodermis.

In dicot, root hypodermis is absent whereas, in dicot stem, hypodermis is present.

In dicot root endodermis shows Casparian bands, whereas in dicot stem endodermis contains starch grains in its cells.

In dicot root pericycle is parenchymatous, take part in the lateral formation and secondary growth, whereas in dicot stem, pericycle is discontinuous, sclerenchymatous, present in the form of patches over the vascular bundles.

In dicot root, vascular bundles are radial, whereas in dicot stem vascular bundles are collateral, conjoint, open

In dicot, root xylem is exarch, whereas in dicot stem xylem is endarch.

In dicot, root medulla is reduced, whereas in dicot stem is xylem is endarch.

In dicot root, conjunctive tissue is present, whereas, in dicot stem, medullary rays are present.

So, the correct option is ‘Protoxylem’