Roots

1. The main function of root hairs is: (BPSC 64th Prelims)
   a) Reproduction
   b) Photosynthesis
   c) Absorption of water and minerals
   d) Transpiration
   Answer: c
   Explanation: Root hairs increase surface area and absorb water and dissolved minerals from the soil.

2. Tap root system is generally found in: (UPSC Prelims 2013)
   a) Monocots
   b) Dicots
   c) Gymnosperms
   d) Algae
   Answer: b
   Explanation: Dicotyledonous plants have a tap root system that grows deep into the soil.

3. Which of the following is a modified root for storage? (BPSC 66th Prelims)
   a) Carrot
   b) Onion
   c) Potato
   d) Ginger
   Answer: a
   Explanation: Carrot is a tap root modified for storage of food.

4. Roots develop from which part of the embryo? (BPSC 60–62nd Prelims)
   a) Cotyledon
   b) Plumule
   c) Radicle
   d) Epicotyl
   Answer: c
   Explanation: The radicle is the embryonic root that develops into the root system.

5. Adventitious roots are found in: (UPPSC 2016)
   a) Mango
   b) Mustard
   c) Grass
   d) Pea
   Answer: c
   Explanation: In grasses and other monocots, adventitious roots arise from parts other than the radicle.

6. Which of the following plants shows pneumatophores? (BPSC 65th Prelims)
   a) Banyan
   b) Mango
   c) Rhizophora
   d) Wheat
   Answer: c
   Explanation: Rhizophora (a mangrove) has pneumatophores that help in gaseous exchange in swampy conditions.

7. Which type of root modification is seen in prop roots of banyan? (BPSC 67th Prelims)
   a) Mechanical support
   b) Food storage
   c) Respiration
   d) Photosynthesis
   Answer: a
   Explanation: Prop roots of banyan tree provide mechanical support by growing from branches to the ground.

8. Fibrous roots arise from: (UPSC Prelims 2011)
   a) Plumule
   b) Radicle
   c) Base of the stem
   d) Epicotyl
   Answer: c
   Explanation: In fibrous root systems (monocots), roots emerge from the base of the stem.

9. The root cap is absent in: (BPSC 63rd Prelims)
   a) Banyan
   b) Mustard
   c) Hydrilla
   d) Pea
   Answer: c
   Explanation: Aquatic plants like Hydrilla lack root caps and instead have root pockets.

10. In which plant are stilt roots seen? (BPSC 68th Prelims)
    a) Maize
    b) Mango
    c) Mustard
    d) Banyan
    Answer: a
    Explanation: Maize develops stilt roots from lower nodes for additional support.

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NCERT-Based Questions (Q11–30)

1. Which part of the plant anchors it firmly in the soil?
   a) Stem
   b) Leaves
   c) Roots
   d) Flowers
   Answer: c
   Explanation: Roots anchor the plant and absorb water and minerals from the soil.

2. Which root system is characteristic of monocots?
   a) Tap root system
   b) Fibrous root system
   c) Lateral root system
   d) Adventitious root system
   Answer: b
   Explanation: Monocots have fibrous root systems, which consist of thin, branched roots.

3. In which plant is the root modified for nitrogen fixation?
   a) Mustard
   b) Soybean
   c) Carrot
   d) Potato
   Answer: b
   Explanation: Soybean roots have nodules containing nitrogen-fixing bacteria (Rhizobium).

4. The region of root involved in the absorption of water is:
   a) Region of meristematic activity
   b) Region of elongation
   c) Region of maturation
   d) Root cap
   Answer: c
   Explanation: Root hairs present in the region of maturation absorb water and minerals.

5. Which part of the root protects the tip from injury?
   a) Root hair
   b) Root cap
   c) Root cortex
   d) Pericycle
   Answer: b
   Explanation: Root cap protects the delicate meristematic tissue at the root tip.

6. Which root modification helps in respiration?
   a) Prop root
   b) Pneumatophore
   c) Conical root
   d) Fusiform root
   Answer: b
   Explanation: Pneumatophores are aerial roots that allow respiration in waterlogged soils.

7. Carrot is an example of which type of root modification?
   a) Conical
   b) Tuberous
   c) Fusiform
   d) Napiform
   Answer: a
   Explanation: Carrot is a conical root — wide at the top and tapering towards the bottom.

8. Roots that grow from any part other than the radicle are called:
   a) Lateral roots
   b) Adventitious roots
   c) Tap roots
   d) Primary roots
   Answer: b
   Explanation: Roots arising from stems or leaves are called adventitious roots.

9. The root system in dicots is:
   a) Fibrous
   b) Tap root
   c) Adventitious
   d) All of the above
   Answer: b
   Explanation: Dicotyledons typically possess a tap root system.

10. The innermost layer of the root cortex is:
    a) Epidermis
    b) Endodermis
    c) Pericycle
    d) Stele
    Answer: b
    Explanation: Endodermis is the innermost layer of cortex, controlling movement into vascular tissues.

11. Lateral roots arise from:
    a) Epidermis
    b) Cortex
    c) Pericycle
    d) Endodermis
    Answer: c
    Explanation: Lateral roots originate from the pericycle, just inside the endodermis.

12. Which layer in roots regulates the flow of water into the xylem?
    a) Cortex
    b) Endodermis
    c) Pericycle
    d) Epidermis
    Answer: b
    Explanation: Endodermis acts as a selective barrier for water and nutrients entering the vascular cylinder.

13. Which element is essential for root development?
    a) Nitrogen
    b) Potassium
    c) Phosphorus
    d) Calcium
    Answer: c
    Explanation: Phosphorus is essential for strong root growth and energy transfer.

14. Roots that store food are called:
    a) Adventitious roots
    b) Modified roots
    c) Epiphytic roots
    d) Tuberous roots
    Answer: b
    Explanation: Modified roots store nutrients and are found in plants like carrot and beetroot.

15. Sweet potato is a modified:
    a) Root
    b) Stem
    c) Leaf
    d) Fruit
    Answer: a
    Explanation: Sweet potato is a tuberous root modified for food storage.

16. Which of the following roots gives rise to a symbiotic relationship with fungi?
    a) Tap root
    b) Fibrous root
    c) Mycorrhizal root
    d) Prop root
    Answer: c
    Explanation: Mycorrhizae are symbiotic associations between fungal hyphae and plant roots.

17. The process of root elongation occurs in:
    a) Region of elongation
    b) Root cap
    c) Region of maturation
    d) Region of cell division
    Answer: a
    Explanation: The region just behind the root cap where cells elongate is called the elongation region.

18. Which plant shows fasciculated root?
    a) Asparagus
    b) Beet
    c) Maize
    d) Pea
    Answer: a
    Explanation: Fasciculated roots are clustered tuberous roots, seen in Asparagus and Dahlia.

19. Which root type gives additional support to tall plants?
    a) Tap root
    b) Lateral root
    c) Prop root
    d) Primary root
    Answer: c
    Explanation: Prop roots grow from branches and support heavy plants like the banyan tree.

20. In which plant are nodulated roots used for nitrogen fixation?
    a) Pea
    b) Wheat
    c) Rice
    d) Maize
    Answer: a
    Explanation: Pea plants have root nodules that fix atmospheric nitrogen through symbiosis with Rhizobium.

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Predicted/Reference Book-Based Questions (Q31–50)

1. Epiphytic roots help in:
   a) Absorbing minerals
   b) Fixing nitrogen
   c) Photosynthesis
   d) Absorbing moisture from air
   Answer: d
   Explanation: Epiphytic roots (as in orchids) absorb moisture from the atmosphere using spongy tissue called velamen.

2. What type of roots are present in wheat?
   a) Tap root
   b) Fibrous root
   c) Tuberous root
   d) Adventitious root
   Answer: b
   Explanation: Wheat, a monocot, has fibrous roots.

3. Which root modification helps in mechanical support in sugarcane?
   a) Tuberous root
   b) Prop root
   c) Stilt root
   d) Pneumatophore
   Answer: c
   Explanation: Stilt roots grow obliquely and provide support, common in sugarcane and maize.

4. Which root develops from a cut stem or leaf?
   a) Tap root
   b) Adventitious root
   c) Fibrous root
   d) Lateral root
   Answer: b
   Explanation: Roots developing from parts other than radicle are adventitious.

5. The tissue present at the tip of roots for continuous growth is:
   a) Collenchyma
   b) Parenchyma
   c) Meristematic tissue
   d) Xylem
   Answer: c
   Explanation: Apical meristem at the root tip helps in primary growth.

6. The Casparian strip is present in:
   a) Pericycle
   b) Cortex
   c) Endodermis
   d) Epidermis
   Answer: c
   Explanation: Casparian strips in endodermis prevent uncontrolled water movement across cell walls.

7. Prop roots arise from:
   a) Main stem
   b) Branches
   c) Leaves
   d) Root hairs
   Answer: b
   Explanation: In banyan tree, prop roots grow downward from branches to provide support.

8. In monocots, the root system is:
   a) Deep and tapering
   b) Fibrous and shallow
   c) Taproot with root hairs
   d) Fused
   Answer: b
   Explanation: Monocots have fibrous, shallow root systems spreading laterally.

9. In legumes, the function of nodules is to:
   a) Absorb water
   b) Fix carbon
   c) Store food
   d) Fix nitrogen
   Answer: d
   Explanation: Legume root nodules contain Rhizobium bacteria that fix atmospheric nitrogen.

10. Modified roots for respiration are seen in:
    a) Dahlia
    b) Orchid
    c) Mangroves
    d) Pea
    Answer: c
    Explanation: Mangroves like Rhizophora grow pneumatophores for gaseous exchange.

11. Root hair develops from:
    a) Endodermis
    b) Pericycle
    c) Epidermis
    d) Cortex
    Answer: c
    Explanation: Root hairs are unicellular extensions of epidermal cells that absorb water.

12. Which of the following helps in vegetative propagation via roots?
    a) Rose
    b) Mango
    c) Guava
    d) Sweet potato
    Answer: d
    Explanation: Sweet potato reproduces vegetatively through tuberous roots.

13. The plant Tinospora (Giloy) shows:
    a) Pneumatophores
    b) Epiphytic roots
    c) Hanging roots
    d) Climbing roots
    Answer: d
    Explanation: Giloy has climbing roots that help it to twine around support.

14. Root pressure is caused by:
    a) Osmosis
    b) Transpiration
    c) Photosynthesis
    d) Respiration
    Answer: a
    Explanation: Osmosis causes water to enter the root xylem, generating root pressure.

15. Nodule-forming bacteria enter the plant root through:
    a) Stomata
    b) Root cap
    c) Root hairs
    d) Cortex
    Answer: c
    Explanation: Rhizobium enters the root through root hairs to form nodules.

16. Which layer is involved in lateral root formation?
    a) Pericycle
    b) Endodermis
    c) Epidermis
    d) Xylem
    Answer: a
    Explanation: Lateral roots arise from the pericycle in dicot plants.

17. Which plant has napiform root?
    a) Carrot
    b) Turnip
    c) Sweet potato
    d) Asparagus
    Answer: b
    Explanation: Turnip has napiform roots — spherical with a tapering end.

18. The absorption of minerals is carried out mainly by:
    a) Cortex
    b) Root cap
    c) Root hairs
    d) Pericycle
    Answer: c
    Explanation: Root hairs absorb minerals and water from the soil.

19. The function of pericycle includes:
    a) Absorption
    b) Protection
    c) Lateral root formation
    d) Photosynthesis
    Answer: c
    Explanation: Pericycle is the origin point for lateral roots in dicots.

20. Which structure helps in penetration of roots into the soil?
    a) Root cap
    b) Root hair
    c) Meristem
    d) Phloem
    Answer: a
    Explanation: Root cap covers and protects the growing tip as it penetrates soil.