NCERT solution for class 9 science tissues ( Chapter 6)

Solution for Exercise Questions

1. Define the term ’tissue’?
Answer :

Tissue is defined as a group of cells similar in structure and function.

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

The types of elements together make up the xylem tissue, which are:
1. Vessels

2. Tracheids

3. Xylem fibres

4. Xylem parenchyma

3. How are simple tissues different from complex tissues in plants?
Answer :

Simple tissues are made up of a single type of cell that performs only one common function whereas complex tissues are made up of more than one kind of a cell that coordinate to perform one particular function.

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

Difference between parenchyma, collenchyma and sclerenchyma on the basis of their cell wall is:
Parenchyma: Cell walls are thin and made up of cellulose.

Collenchyma: Cell walls are thick at the edges due to the deposition of pectin.

Sclerenchyma: Cell walls are thick due to the deposition of lignin.

5. What are the functions of the stomata?
Answer :

Stomata are tiny pores present on the outer layer of the cells known as the epidermis. Stomata helps in the exchange of gases and transpiration.

6. Diagrammatically show the difference between the three types of muscle fibres.
Answer :

Striated muscles

Smooth muscles

Striated muscles

1.They are connected with bones

1. Found in lungs and alimentary canal.

1. Present in the heart.

2. They possess many nuclei.

3. Voluntary in nature..

3. Involuntary in nature.

3. Involuntary in nature.

2. They have 1 nucleus.

2. They have 1 nucleus.

7. What is the specific function of the cardiac muscle?
Answer :

The specific function of the cardiac muscle is to show rhythmic contraction and relaxation throughout life.

8. Differentiate between striated, un-striated and cardiac muscles on the basis of their structure and site/location in the body.
Answer :

Striated muscles

Un-striated muscles

Cardiac muscles

Long, cylindrical, non – tapering.

Long and tapering.

Cylindrical and non – tapering.

Location in the body is hands, legs and skeletal muscles

Location in the body is wall of stomach, intestine, ureter and bronchi

Location in the body is heart

They are un-branched.

They are un – branched.

They are branched.

9. Draw a labelled diagram of a neuron.
Answer :

10. Name the following.

(a) Tissue that forms the inner lining of our mouth.

(b) Tissue that connects muscle to bone in humans.

(c) Tissue that transports food in plants.

(d) Tissue that stores fat in our body.

(e) Connective tissue with a fluid matrix.

(f) Tissue present in the brain.
Answer :

(a) The epithelial tissue, Squamous epithelium.

(b) Tendon

(c) Phloem

(d) Adipose tissue

(e) Blood, it is a fluid connective tissue

(f) Nervous tissue

11. Identify the type of tissue in the following:
Skin, bark of tree, bone, lining of kidney tubule, vascular bundle.
Answer :

The type of tissue in the following are:

Skin: Striated squamous epithelial tissue

Bark of tree: Protective tissue and cork

Bone: Connective tissue

Lining of kidney tubule: Cuboidal epithelial tissue

Vascular bundle: Conducting tissue(xylem and phloem). Complex permanent tissue

12. Name the regions in which parenchyma tissue is present.
Answer :

The parenchyma is found in the pith of stems and roots. When parenchyma contains chlorophyll it is called as chlorenchyma, it is found in green leaves. Parenchyma found in aquatic plants has large air cavities which enables them to float and are hence called aerenchyma.

13. What is the role of epidermis in plants?
Answer :

The epidermis in plants forms an uninterrupted and continuous layer that has no intercellular space thereby providing protection to the parts of plant.

14. How does the cork act as a protective tissue?
Answer :

The cork act as a protective tissue because its cells are dead and the arrangement of cells is so dense, that there is no intercellular space. Deposition of suberin is observed on the walls of the cells that make them impervious to water and gases.

15. Complete the following chart.
Answer :

Solution for Intext Question

1. What is a tissue?
Answer :

A group of cells that are similar in structure and/or work together to achieve a particular function are called tissue.

2. What is the utility of tissues in multicellular organisms?
Answer :

The use of tissues in multicellular organisms is to provide structural and mechanical strength and allow division of labour.

1. Name types of simple tissues.
Answer :

The types of simple tissues are as follows:
1. Parenchyma

2. Collenchyma

3. Sclerenchyma

4. Aerenchyma

2. Where is apical meristem found?
Answer :

Apical meristem is present at the growing tips of stems and roots and increases the length of the stem and the root.

3. Which tissue makes up the husk of coconut?
Answer :

The tissue which makes up the husk of the coconut is Sclerenchymatous tissue.

4. What are the constituents of phloem?
Answer :

The phloem constitutes of the following four elements:
1.Sieve tube

2. Companion cells

3.Phloem parenchyma

4.Phloem fibres

1. Name the tissue responsible for movement of our body.
Answer :

The tissue responsible for movement of our body are:
1. Muscular tissue

2. Nervous tissue

2. What does a neuron look like?
Answer :

A neuron consists of a cell body with a nucleus and cytoplasm, from which long thin hair-like parts arise. Usually each neuron has a single long part, called the axon, and many short, branched parts called dendrites. An individual nerve cell may be up to a metre long. Many nerve fibres bound together by connective tissue make up a nerve.

3. Give three features of cardiac muscles.
Answer :

The following are 3 features of the cardiac muscles:
1. They are cylindrical in shape.

2. Striated muscle fibers.

3. They are uninucleated and branched.

4. What are the functions of areolar tissue?
Answer :

Areolar tissue are a type of connecting tissues found between the skin and muscles, around blood vessels and nerves and in the bone marrow. It fills the space inside the organs, supports internal organs and helps in repair of tissues. They support the delicate internal organs and assist in tissue repair in case of damage.