6. Tissues Class 9 Science Chapter 6 NCERT Solutions (CBSE)
CBSE Class 9 Science Chapter 6 : Tissues – Full NCERT Textbook Solutions
Chapter 6 :Tissues
Internal Question :
1. What is a tissue?
Answer : Tissue is a group of cells similar in structure and function.
2. What is the utility of tissues in multi-cellular organisms?
Answer : The utility of tissues in multi-cellular organisms is the division of labour. Tissues group similar cells to perform a specific function efficiently, ensuring the organism's overall survival and proper functioning.
Internal Question :
1. Name types of simple tissues.
Answer : The types of simple tissues in plants are parenchyma, collenchyma and sclerenchyma.
2. Where is apical meristem found?
Answer : Apical meristem is found at the tips of roots and stems in plants, where it is responsible for primary growth.
3. Which tissue makes up the husk of coconut ?
Answer: The husk of coconut is made up of sclerenchyma tissue. This tissue consists of dead cells with thick cell walls, which provide strength and toughness to the coconut husk.
4. What are the constituents of phloem ?
Answer: Phloem is made up of four main elements: sieve tubes, companion cells, phloem parenchyma and phloem fibres. These work together to transport food (mainly sugars) from leaves to different parts of the plant.
Internal Question :
1. Name the tissue responsible for movement in our body.
Answer : The tissue responsible for movement in our body is muscular 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. These parts help the neuron to receive and transmit messages in the body.
3. Give three features of cardiac muscles.
Answer : Cardiac muscles have the following features:
(i) They are involuntary muscles and work without our control.
(ii) Their cells are cylindrical, branched and connected to each other.
(iii) They contract and relax continuously without getting tired.
4. What are the functions of areolar tissue?
Answer : The functions of areolar tissue are:
(i) It fills the space inside organs.
(ii) It helps in repair of tissues.
(iii) It supports internal organs and helps in packing them.
Exercises of Chapter 6 :Tissues
1. Define the term “tissue”.
Answer : A tissue is a group of similar cells along with intercellular substance that work together to perform a specific function.
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. They are: (i) Tracheids (ii) Vessels (iii) Xylem parenchyma (iv) Xylem fibres
3. How are simple tissues different from complex tissues in plants?
Answer : The difference between Simple and Complex Tissues in Plants:
|
Simple Tissues |
Complex Tissues |
|
Made up of only one type of cells |
Made up of more than one type of cells |
|
Cells are similar in structure and function |
Cells are different in structure and function |
|
Mainly help in support and storage |
Mainly help in transport of water, minerals and food |
|
Examples: Parenchyma, Collenchyma, Sclerenchyma |
Examples: Xylem, Phloe |
4. Differentiate between parenchyma, collenchyma and sclerenchyma on the basis of their cell wall.
Answer : The differentiation on the basis of their cell wall is :
|
Tissue |
Cell Wall |
|
Parenchyma |
Thin cell wall (made of cellulose). |
|
Collenchyma |
Cell wall is thick at the corners (due to pectin and cellulose). |
|
Sclerenchyma |
Very thick cell wall (due to lignin), making it hard and stiff. |
5. What are the functions of the stomata?
Answer : The functions of stomata are:
(i) They help in the exchange of gases (oxygen and carbon dioxide).
(ii) They help in transpiration (loss of water vapor from the plant surface).
6. Diagrammatically show the difference between the three types of muscle fibres.
Answer :
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 without getting tired, which helps to pump blood to all parts of the body.
8. Differentiate between striated, unstriated and cardiac muscles on the basis of their structure and site/location in the body.
Answer : The difference between Striated, Unstriated and Cardiac Muscles:
|
Muscle Type |
Structure |
Site/Location in Body |
|
Striated Muscles |
Long, cylindrical and unbranched fibres with clear striations (light and dark bands), multinucleate |
Found attached to bones (like in arms and legs) |
|
Unstriated Muscles |
Spindle-shaped cells without striations, single nucleus |
Present in walls of internal organs like stomach, intestine, blood vessels |
|
Cardiac Muscles |
Cylindrical, branched fibres with striations and single nucleus |
Found only in the walls of the heart |
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 tissue that forms the inner lining of our mouth is called epithelial tissue (squamous epithelium).
(b) The tissue that connects muscle to bone in humans is called tendon.
(c) The tissue that transports food in plants is called phloem.
(d) The tissue that stores fat in our body is called adipose tissue.
(e) The connective tissue with a fluid matrix is called blood.
(f) The tissue present in the brain is called 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:
(i) Skin → Epithelial tissue
(ii) Bark of tree → Protective tissue (cork)
(iii) Bone → Connective tissue
(iv) Lining of kidney tubule → Epithelial tissue (cuboidal epithelium)
(v) Vascular bundle → Complex permanent tissue (xylem and phloem)
12. Name the regions in which parenchyma tissue is present.
Answer : Parenchyma tissue is present in the soft parts of plants such as the cortex and pith of stems and roots, mesophyll of leaves, and in fruits.
13. What is the role of epidermis in plants?
Answer : The role of epidermis in plants is to provide protection against water loss, mechanical injury, and invasion by parasites or fungi. It also helps in exchange of gases through stomata and absorption of water (in roots).
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 without intercellular spaces. Their walls contain suberin, which makes them waterproof and prevents loss of water, entry of harmful substances and protects the plant from injury and infection.
15. Complete the following chart:
Answer:
Posted 4 months ago