Tissues | NCERT solutions | class 9 science

CHAPTER - 6

NCERT Questions

Page 69

Ans1.
A group of cells that are similar in structure and work together to do a particular function is called tissue.

Ans2.
Tissues provide structural strength, mechanical strength, show division of labour for better organisation.

Page 74

Ans1.
Parenchyma, Collenchyma, sclerenchyma.

Ans2.
Apical meristem is found at the tip of root or shoot of the plant.

Ans3.
Sclerenchyma tissue.

Ans4.
1. Sieve tubes

2. Phloem fibres

3. Companion cells

4. Phloem parenchyma

Page 78

Ans1.
Muscular tissue, Nervous tissue. Combination of both of these tissues.

Ans2.
A neuron consists of a cell body with a nucleus and cytoplasm. Each neuron has a single long part called the axon and many small, short branched parts called dendrite. An individual nerve cell is called neuron, it may be up to a metre long.

Ans3.
Three features of cardiac muscles are :-

1. They control the contraction and relaxation of the heart.

2. Cardiac muscles are cylindrical, branched and uninucleate.

3. Cardiac muscles are involuntary muscles that cannot be controlled by us.

Ans4.
1. These are connective tissues that support internal organs.

2. They fills the space inside the organs.

3. They found between skin and muscles around the blood vessels.

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