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)

Monocot characteristics are

  1. Fibrous root system, parallel-veined leaves, trimerous flowers and two cotyledons

  2. Fibrous root system, parallel-veined leaves, trimerous flowers and one cotyledon

  3. Fibrous root system, reticulate veined leaves, trimerous flowers and one cotyledon

  4. Tap root system, parallel venation, trimerous flowers and one cotyledon
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Monocot plants, as the name suggests have only one cotyledon. these plants have characteristic features like fibrous root system because the radicle is short-lived, thus replaced by adventitious roots. They also have parallel-veined leaves and trimerous flowers.

So the correct answer is 'Fibrous root system, parallel-veined leaves, trimerous flowers, and one cotyledon'.

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)

Oil cavities of Citrus are

  1. Lysigenous

  2. Schizogeneous

  3. Schizolysigneous

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

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. The secretory cavities in Eucalyptus, Citrus and Gossypium are good examples.

So, the correct answer is 'Lysigenous.'

Multiple choice properties of enzyme enzyme properties enzymes biomolecules: chemical constituents of living cells biology

Tyloses

  1. Are ballon-like swelling of xylem parenchyma cells in the lumen of vessels

  2. Are found in heartwood

  3. Make heartwood functional

  4. Both (A) and (B)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Tyloses are outgrowths on parenchyma cells of xylem vessels of secondary heartwood. When the plant is stressed by drought or infection, tyloses will fall from the sides of the cells and "dam" up the vascular tissue to prevent further damage to the plant. 
So the correct option is 'Are ballon-like swelling of xylem parenchyma cells in the lumen of vessels'.
Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

Mature anther contains

  1. One wall layer, two microsporangia

  2. Two wall layers, one microsporangium

  3. Four wall layers and four microsporangia

  4. Two wall layers, four microsporangia
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Structure of anther contains four wall layers:-

i)Epidermis, endothecium and middle layer that function as a protective layer.
ii)Inner most layer tapetum provide nutrition to the pollen.
iii)It contains four microsporangia two in each lobe which give rise to microspore mother cell.
So the correct option is 'Four wall layers and four microsporangia'.

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

Intine layer of pollen grain is made up of

  1. Inner cellulose, outer pectin

  2. Outer cellulose, inner pectin

  3. Only with cellulose

  4. Only with pectin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  • Pollen grains are a mass of microspores in a seeded plant which appears in the form of fine dust. 
  • Each pollen grain is a minute body with varying shape and structure which are formed in the anthers of angiosperms.
  • It consists of two layers:-
1) Intine or inside layer is a thin and continuous layer made of cellulose or hemicellulose and pectin.
2) Exine or outer layer a highly decay-resistant chemical called sporopollenin.

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

The pollen grain is related to the embryosac as

  1. Male gametophyte is to the egg

  2. Male gametophyte is to the female gametophyte

  3. Sperm is to the egg

  4. Sperm is to the female gametophyte
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  1. The pollen grain is the male gametophyte that produces two mature male gametes vegetative and generative cell.
  2. Embryo sac is the female gametophyte that contains a thin sac within the nucellus that contains egg which is female gamete.
As male and female gamete fuse to form the egg, in same way pollen grain and embryosac related with each other to hold them.
So the correct option is 'Male gametophyte is to the female gametophyte'.

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

Exine of pollen grains is composed of 

  1. Pectocellulose

  2. Lignocellulose

  3. Sporopollenin

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

Most of the pollen grains consists of three distinct parts. The central cytoplasmic part is the source of nuclei responsible for fertilization. The other parts constituting the wall of the grains are an inner layer, the intine, and an outer layer, the exine. the outer and the most durable layer, the exine, is very resistant to disintegration. The constituents of the exine have been termed as the sporopollenin.

So, the correct option is 'Sporopollenin'. 

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

The study of mature outer morphology of pollen grains is known as

  1. Polynology

  2. Palynology

  3. Andrology

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

The study of the mature outer morphology of pollen grains and other spores is known as palynology mainly includes pollen that is found in archaeological and geological deposits. These are used for radiocarbon dating and helps to study the ancient climate and environment by knowing the type of plant that grows at that time.

So, the correct option is 'Palynology'

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

Which of the following event mainly affected in the absence of generative cell within pollen-grain?

  1. Entry of pollen-tube inside the embryo sac

  2. Double fertilization

  3. Growth of pollen-tube inside the style

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

The generative cell in a pollen grain divides to form two male gametes, which are essential for double fertilization (one fertilizes the egg cell, the other fuses with the central cell). Without the generative cell, double fertilization cannot occur.

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

The carrier of male gametes in seed plants is

  1. Water

  2. Air

  3. Pollen grains

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

Seed plants are referred to angiosperms, in which seeds are present and are covered. They have male and female gametes that are responsible for fertilization. The male gametes are produced in larger numbers than the female gametes. These male gametes are the carrier of pollen grains while female gametes are the carrier of eggs or ovules. In pollination, the pollen grains are carried through wind, water or insects to the stigma of another flower.

So, the correct option is 'Water, Air, Insects, and Pollen grains'.

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

The male gametes of angiosperms are

  1. Uniflagellate

  2. Biflagellate

  3. Non-motile as there is no flagellated stage in the life cycle of angiosperms

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

The male gametes of angiosperms consist of two sperm cells within a pollen grain or a pollen tube. They are derived from a single generative cell, which is formed as the smaller cell by unequal cell division in the microspore after meiosis. The gametes formed will be non-motile as there is no flagellated stage in the life cycle of angiosperms.

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

Outermost layer of the pollen is formed from ..........

  1. Pectocellulose

  2. Lignocellulose

  3. Sporopollenin

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

Sporopollenin is major component of the tough outer walls called as exine of plant spores and pollen grains. It is chemically very stable and is usually well preserved in soils and sediments. The exine layer is often intricately sculptured in species-specific patterns, allowing material recovered from lake sediments to provide useful information to palynologists about plant and fungal populations in the past. The chemical composition of sporopollenin is not exactly known, due to its unusual chemical stability and resistance to degradation by enzymes and strong chemical reagents.