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 leaf - external morphology morphology of leaf structure of a leaf the leaf

Common features between lenticels and hydrathodes are

  1. Both 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 plant
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Lenticels and hydathodes both lack guard cells and hence, their openings are not regulated. Hydathodes are openings at end of vascular supply to leaves and are involved in the process of guttation, which is loss of water in liquid form. Lenticels are lens shaped openings in big woody trunks of trees for gaseous exchange.

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Leaf primordium grows into adult lamina by means of

  1. Marginal meristem

  2. Lateral meristem

  3. First apical and then, marginal meristem

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

Plants have three types of meristems, the apical meristem, the intercalary meristem and the lateral meristem. Leaves are derived from shoot apical meristem which swells to form undifferentiated leaf primordium which divides into two systems that develop leaf blades and leaf sheaths. The growth of leaf blades occurs due to cells division but is mainly from cell elongation. The flattened blade form is derived from the marginal meristem present at the margins of leaf axis. Meristem present at the sides and causes increase in girth of the plant is termed as lateral meristem and is not involved in leaf formation.
Therefore, the correct answer is option C.

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Identify the plant, if veins are appearing parallel on leaves.

  1. The plant is a dicot

  2. The plant is a monocot

  3. The plant is a gymnosperm

  4. The plant is an angiosperm

  5. The plant is a bryophyte
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

If the veins on the the leaf run parallel to each other throughout the leaf, it is known as parallel venation. It is a feature of monocotyledonous plant. This type of veins are found in grasses.

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Ground tissue gives rise to

  1. Cuticle

  2. Epidermis

  3. Mesophyll

  4. Phloem

  5. Xylem
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ground tissue system comprises of simple permanent tissues like parenchyma, collenchyma and sclerenchyma. In leaves, the ground tissue consists of thin-walled chloroplast containing cells known as palisade mesophyll cells. 

So, the correct answer is 'Mesophyll cells'.

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Monocot leaf can be distinguished from the dicot

  1. Stomata is equally distributed on both lower and upper epidermis

  2. Palisade cells on both upper and lower sides

  3. Several veins of nearly uniform size

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
 Monocot leaf  Dicot leaf
 (i) The monocot leaf is of isobilateral symmetry.  The dicot leaf is of dorsiventral  symmetry.
 (ii) The bullifom cells are present on the upper epidermis.   The bulliform cells are absent.
 (iii) Stomata are equally distributed on both surfaces.   Stomata are present more in lower  surface and few on upper surface.
 (iv) In mesophyll cells, only spongy parenchyma is present with small intercellular spaces.  Mesophyll cells are made up of  palisade parenchyma and spongy  parenchyma with large intercellular  spaces.
 (v) Bundle sheath is made up of parenchyma and just above and below sclerenchymatous cells are found.  Bundle sheath is made up of  parenchyma and just above and below  the parenchymatous or  collenchymatous cells are found.
Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Presence of sheathing leaf base and ligule are characteristic of

  1. Cycas leaf

  2. Fern leaf

  3. Banana leaf

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

A ligule is an outgrowth present at the junction of leaf sheath and lamina in grass leaf. It occurs at the end of petiole at the leaf base. It is a strap-shaped extension of the corolla. It is a membranous appendages. Grass leaf also has sheathing leaf base. 

Thus, the correct answer is 'Grass leaf.'

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Largest number of chloroplasts in the leaf is in.

  1. Spongy tissue

  2. Palisade tissue

  3. Guard cells

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

A. Spongy tissue – parenchyma with less number of chloroplast.

B. Palisade tissue – parenchyma with more number of chloroplast.

C. Guard tissue – modified epidermal cells with chloroplast, present in the stomata.

D. Bundle sheath – Thick walled parenchymatous sheath present around the vascular bundles in leaves.

So, the correct option is ‘Palisade tissue’.

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Petiole part of the leaf is also known as

  1. Epipodium

  2. Mesopodium

  3. Hypopodium

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

The foliage leaf consists of three parts, namely leaf base, petiole and lamina. The leaf base is also called as hypopodium. The petiole part of the leaf is also called as mesopodium. The lamina part of the leaf is called as epipodium.

Thus, the correct answer is 'Mesopodium.'

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Leaf base is sheathing in

  1. Wheat

  2. Maize

  3. Grass

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

In grasses and many monocots, the leaf base (petiole) is broad and surrounds the stem as an envelope. Such a leaf base is known as sheathing leaf base. In grasses such as wheat, maize and grass, the sheathing leaf base protects the intercalary meristem. Hence, the plants belonging to family Poaceae have sheathing leaf base.

So, the correct answer is 'All of the above'.

Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Plastochron is

  1. Period between two successive leaf primordia

  2. Distance between two successive leaf primordia

  3. Region of origin of root branch

  4. Region of origin of stem branch
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • Plastochron is the time interval between the two successive events during the growth of plants.
  • As in the case, when the shoot tip of a plant grows new leaves are produced at regular time intervals.
  • This time interval between the beginning of leaf growth at 2 consecutive nodes in a growing shoot apex by keeping the temperature constant is called Plastochron.
  • So, the correct answer is 'Period between two successive leaf primordia'
Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Period between initiation of two successive leaves or nodes is

  1. Plastochron

  2. Diurnal cyclicity

  3. Internode

  4. Allelopathy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • When the shoot tip of a plant grows new leaves which are produced at regular time intervals.
  • This time interval between the beginning leaf growth at 2 consecutive nodes in a growing shoot apex by keeping the temperature constant is called plastochron.
  • So, the correct answer is 'Plastochron'
Multiple choice botany leaf - external morphology morphology of leaf structure of a leaf the leaf

Which one of the following statements is not correct?

  1. In Capparis, aphylla, stipules become modified into spines

  2. In Nerium, sunken stomata are present on both upper and lower epidermis and lower epidermis

  3. In Asparagus roots store water

  4. In the needle of Pinus roxburghii, sclerenchymatous hypodermis is present
Reveal answer Fill a bubble to check yourself
A Correct answer