Class 9th Science Chapter-6 Exercises

Exercises – Chapter 6: Tissues

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Question 1

Define the term “tissue”.

Answer:
A tissue is a group of similar cells having a common origin that work together to perform a specific function.

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Question 2

How many types of elements together make up the xylem tissue? Name them.

Answer:
Xylem tissue is made up of four types of elements:

1. Tracheids

2. Vessels

3. Xylem fibres

4. Xylem parenchyma

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Question 3

How are simple tissues different from complex tissues in plants?

Answer:

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Question 4

Differentiate between parenchyma, collenchyma and sclerenchyma on the basis of their cell wall.

Answer:

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Question 5

What are the functions of the stomata?

Answer:
Functions of stomata:

1. Exchange of gases (O₂ and CO₂)

2. Transpiration (loss of water vapour)

3. Regulation of water balance in plants

Question 6

Diagrammatically show the difference between the three types of muscle fibres.

Answer (what to draw in exam):

• Striated muscle:
  Long, cylindrical fibres with alternate light and dark bands, many nuclei.

• Unstriated muscle:
  Spindle-shaped fibres, no striations, single nucleus.

• Cardiac muscle:
  Branched fibres with striations, single nucleus, connected by intercalated discs.

Question 7

What is the specific function of the cardiac muscle?

Answer:
The cardiac muscle contracts rhythmically and continuously to pump blood throughout the body.

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Question 8

Differentiate between striated, unstriated and cardiac muscles on the basis of their structure and site/location in the body.

Answer:

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Question 9

Draw a labelled diagram of a neuron.

Answer (what to draw):

• Dendrites

• Cell body (cyton)

• Nucleus

• Axon

• Axon terminal

(Draw a neat neuron and label all parts clearly.)

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Question 10

Name the following:

(a) Tissue that forms the inner lining of our mouth
→ Squamous epithelium

(b) Tissue that connects muscle to bone in humans
→ Tendon

(c) Tissue that transports food in plants
→ Phloem

(d) Tissue that stores fat in our body
→ Adipose tissue

(e) Connective tissue with a fluid matrix
→ Blood

(f) Tissue present in the brain
→ Nervous tissue

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Question 11

Identify the type of tissue in the following:

Question 12

Name the regions in which parenchyma tissue is present.

Answer:
Parenchyma tissue is present in:

• Cortex and pith of stems and roots

• Mesophyll of leaves

• Fleshy parts of fruits

• Seeds and endosperm

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Question 13

What is the role of epidermis in plants?

Answer:
The epidermis forms the outer protective layer of plants. Its main roles are:

• Protection from mechanical injury and infection

• Prevention of water loss by cuticle

• Gas exchange through stomata

• Absorption of water and minerals in roots (root hairs)

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Question 14

How does the cork act as a protective tissue?

Answer:
Cork acts as a protective tissue because:

• Its cells are dead and tightly packed

• Cell walls are coated with suberin, which makes them impermeable to water and gases

• It protects the plant from water loss, pathogens, and mechanical damage

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Question 15

Complete the following chart: