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

Consider the following statements: (a) Vessels are composed of row of cells, cylindrical tubes with wide ends and long in size. (b) Vascular bundle in which cambium is present is called open bundle. (c) Annual rings do not occur in monocot trees growing on sea-shores. Which of the above statements is/are incorrect?

  1. Only (a)

  2. Only (b)

  3. Only (c)

  4. All of these

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement (c) is incorrect. Annual rings do not occur in dicot trees, growing on sea-shores because there is little climatic variation.

Multiple choice

Which of the following types of adventitious root modifications is found in Dahlia?

  1. Tuberous roots

  2. Fasciculated roots

  3. Nodulose roots

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

Dahlia has fasciculated roots, which are characterized by a cluster of swollen tuberous roots arising from the base of the stem. Unlike single tuberous roots (like in sweet potato), fasciculated roots form a bunch-like structure. This is a specialized adventitious root modification for food storage.

Multiple choice

In plant roots, the casparian strip is correctly described by which of the following?

  1. It is located in the walls between endodermal cells and cortex cells.

  2. It provides energy for the active transport of minerals into the vascular bundle from the cortex.

  3. It ensures that all minerals are absorbed from the soil in equal amounts.

  4. It ensures that all water and dissolved substances must pass through a cell before entering the vascular bundle.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The Casparian strip is a waterproof band made of suberin around endodermal cells. It blocks the apoplastic pathway, forcing all water and dissolved minerals to pass THROUGH the cytoplasm of endodermal cells (symplastic pathway) before entering the vascular bundle. This provides selective control over nutrient uptake.

Multiple choice

Which of the following meristems is responsible for extrastelar secondary growth in dictyledonous stem?

  1. Interfascicular cambium

  2. Intercalary meristem

  3. Phellogen

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

Phellogen (cork cambium) is the meristem responsible for extrastelar secondary growth - it produces cork (phellem) outward and secondary cortex (phelloderm) inward. Interfascicular cambium is intrastelar, intercalary meristem is for primary growth at internodes, and intrafascicular cambium is part of the vascular cambium within the vascular bundle.

Multiple choice

Which of the following pairs of plants show modification of axillary buds into tendrils and hooks respectively? I. Hugonia II. Duranta III. Passiflora IV. Dioscorea

  1. I and II

  2. II and III

  3. III and I

  4. IV and I
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Passiflora (passion flower) has tendrils modified from axillary buds for climbing, while Hugonia has hooks modified from axillary buds. Duranta and Dioscorea are not paired correctly in the other options. This is an example of how axillary buds can modify into different climbing structures in different plants.

Multiple choice

Resin duct of a gymnospermous stem is an example of

  1. big vacuole

  2. intercellular space

  3. lysigenous cavity

  4. schizogenous cavity
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Schizogenous cavity is formed either by the separation of neighbouring cell or by disintegration of cells, e.g. resin ducts of gymnosperms.

Multiple choice

Which of the following statements is true for primary xylem in a dicot root showing extensive secondary growth?

  1. It is retained in the centre of the axis.

  2. It gets crushed.

  3. It gets surrounded by primary phloem.

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During extensive secondary growth in dicot roots, the primary xylem remains in the center of the axis and is NOT crushed. Secondary vascular tissues are formed around it, but the central primary xylem persists. This is distinct from primary phloem which gets crushed during secondary growth.

Multiple choice

Secondary phloem remains functional generally

  1. for one year

  2. for less than one year

  3. for more than one year

  4. for as long as the plant lives
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Secondary phloem is formed by vascular cambium during secondary growth in vascular plant. Generally, it remains functional for one year but in some plants more than one year, e.g. Tilia and Salix.

Multiple choice

Match List I (type of tissues/structures) with List II (characterstic features of the tissue) and select the correct answer using codes given below the lists.

 
List I List II
A. Hydrathodes (1) Balloon-like protusions into tracheary elements developed from xylem parenchyma
B. Collenchyma (2) Mechanical tissue that consists of living cells walls rich in pectin and hemicellulose
C. Periblem (3) Occur on leaf tips responsible for guttation
D. Tyloses (4) Meristematic tissue responsible for the development of cortex

  1. A – 2, B – 3, C – 4, D – 1

  2. B – 3, B – 2, C – 1, D – 4

  3. A – 2, B – 3, C – 1, D – 4

  4. A – 3, B – 2, C – 4, D – 1
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The correct matching is: Hydrathodes - (3) leaf tips responsible for guttation; Collenchyma - (2) mechanical tissue with living cells and pectin-rich walls; Periblem - (4) meristem for cortex development (periblem is the ground meristem); Tyloses - (1) balloon-like xylem parenchyma protrusions into tracheary elements.

Multiple choice

Haustorial roots are present in

  1. Zeamays

  2. Cactus

  3. Cuscuta

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

Haustorial roots, also known as sucking roots, found in parasitic plants like cuscuta, are the adventitious roots which enter the most host plant developing contact with xylem and phloem, and suck food and water from them.

Multiple choice

Match the following:

 
A. Meristem i. Photosynthesis, storage
B. Parenchyma ii. Mechanical support
C. Collenchyma iii. Actively dividing cells
D. Sclerenchyma iv. Stomata
E. Epidermal tissue v. Sclereids

  1. A – i, B – iii, C – v, D – ii, E – iv

  2. A – iii, B – i, C – ii, D – v, E – iv

  3. A – ii, B – iv, C – v, D – i, E – iii

  4. A – v, B – iv, C – iii, D – ii, E – i
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A. Meristem               iii. Actively dividing cells B. Parenchyma         i. Photosynthesis, storage C. Collenchyma        ii. Mechanical support D. Sclerenchyma      v. Sclereids E. Epidermal tissue  iv. Stomata

Multiple choice

Which of the following pairs are incorrectly matched?

a. Growth of roots towards the earth - Positive hydrotropism b. Bending of roots towards water - Positive hydrotropism c. Growth of pollen towards the ovule - Positive phototropism d. Winding of tendrills towards the support - Negative thigmotropism

  1. Only a and b

  2. Only a and c

  3. Only b and c

  4. Only c and d

  5. Only b and d
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct option. Growth of pollen towards the ovule - Chemotropism Winding of tendrills towards the support - Positive thigmotropism This is a wrong option as 'b' is correctly matched.  Bending of roots towards water - Positive hydrotropism Winding of tendrills towards the support - Positive thigmotropism

Multiple choice

The growth of pollen tube towards ovule is an example of

  1. phototropism

  2. hydrotropism

  3. chemotropism

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

Tropism means movement in response to stimuli. Plants show movement in response to stimuli.  Chemotropism is the movement of plants in response to chemicals. It can be away or towards chemicals, e.g. growth of pollen tubes towards ovules in response to some chemical substances that are secreted by ovules to attract pollen tubes.

Multiple choice

What is the main storage product of brown algae?

  1. Chrysolaminarin

  2. Fucoxanthin

  3. Laminarin

  4. Phycoerythrin

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

The molecule laminarin is a storage glucan found in brown algae. It is used as a carbohydrate food reserve in the same way that chrysolaminarin is used by phytoplankton. It is created by photosynthesis and is made up of Beta-1,3-(D)-glucan with Beta- 1,6-glucan linkage. This structure is quite similar to the structure of chrysolaminarin.