Class Nine Science Chapter 6 NCERT Solutions
Chapter 6: Tissues
Intext Questions (Page No. 69)
1. What is tissue?
Ans. A group of cells that is similar in structure and/or work together to achieve a particular function forms a tissue.
2. What is the utility of tissues in multicellular organisms?
Ans. There is a division of labour in multicellular organisms. Different functions like digestion, respiration, excretion, etc., is taken up by different groups of cells/tissue. Tissues carry out one particular function and hence, do it efficiently. They are specialised for that particular function.
For example, xylem is specialised to conduct water and minerals.
Intext Questions (Page No. 74)
1. Name types of simple tissues.
Ans. (i) Parenchyma (ii) Collenchyma (iii) Sclerenchyma.
2. Where is apical meristem found?
Ans. It is present at growing tips of stems and roots of plants.
3. Which tissue makes up the husk of coconut?
Ans. Sclerenchyma tissue.
4. What are the constituents of phloem?
Ans. Phloem is made up of four types of elements :
(i) Sieve tubes (ii) Companion cells
(iii) Phloem fibres (iv) Phloem parenchyma
Intext Questions (Page No. 78)
1. Name the tissue responsible for movement in our body.
Ans. Muscular tissue.
2. What does a neuron look like?
Ans. A neuron consists of a flat and broad cell body (also called cyton) with a nucleus and cytoplasm from which long thin hair-like parts called dendrites to arise. Usually, each neuron has a single long part (called the axon) and many short, branched parts called dendrites.
3. Give three features of cardiac muscles.
Ans. Features of cardiac muscles :
(i) Muscles are involuntary.
(ii) Show rhythmic contraction and relaxation.
(iii) Cells are cylindrical, branched and uninucleated.
4. What is the function of areolar tissue?
Ans. It fills the space inside the organs and thus supports them. It also helps in the repair of tissues.
NCERT TEXTBOOK EXERCISES (Page 79)
1. Define the term “tissue”.
Ans. A tissue is a group or collection of similar or dissimilar cells that perform or help to perform a common function and have a common origin.
2. How many types of elements together make up the xylem tissue? Name them.
Ans. Four types of elements together make up Xylem tissue. They are:
(i) Tracheids (ii) Vessels
(iii) Xylem parenchyma (iv) Xylem fibres.
3. How are simple tissues different from complex tissues in plants?
Differentiate between simple tissues and complex tissues.