Class 9 Science Chapter 6 Question Answers - Tissues

Q1: What is the function of epidermis in plants?
Ans: Epidermal tissue forms a protective layer for plants and helps to protect the internal parts of plants which prevent the plant from loss of water, attack by parasitic fungi and outer injury.

Q2: What is the structure of a neuron?
Ans: Building block of a nervous tissue is a neuron. It has a thread-like structure with axon and cell body.

Q3: Where can we find apical meristem?
Ans: It is found in the growing tips of roots and stem. The length of roots and stem is increased due to the presence of apical meristem.

Q4: What do you mean by aerenchyma?
Ans: Aerenchyma is the cell with large air-filled cavities of parenchyma. It helps aquatic plants to float.

Q5: Name two types of plant tissues.
Ans:
(i) Permanent tissue
(ii) Meristematic tissue

Q6: Give the types of meristematic tissues.
Ans:
(i) Intercalary tissue — nodes
(ii) Apical tissue — tips of shoot and roots
(iii) Lateral tissue — stem sides

Q7: Name the tissues which are present in the plants at the nodes.
Ans: Intercalary tissues.

Q8: Define tracheids.
Ans: Tracheids have tapering ends and are basically elongated cells.

Q9: What is the use of tissues in multicellular organisms?
Ans: Tissue provides structural and mechanical strength as well as to allow division of labour in multicellular organisms.

Q10: Where is parenchyma tissue present?
Ans: Parenchyma tissue is present below the epidermis.

Q11: Name the tissue which is responsible for the movement of our body?
Ans: A combination of following two tissues is responsible for the movement of our body :
(i) Muscular t issue
(ii) Nervous tissue

Q12: Write the various functions of all types of epithelial tissues?
Ans: Epithelial tissues help in protection, absorption, excretion, exchange of respiratory gases and secretion.

Q13: How is ligament different from tendons?
Ans: Ligaments are elastic connective tissue which attach bone to bone to keep them in their place. Tendons are less elastic connective tissues which attach muscles to a bone.

Q14: What is the function of connective tissue?
Ans: Connective tissue connects different tissues and organs. It provides support to different parts of the body by forming packing around different organs of the body.

Q15: What will happen if ligaments are over stretched?
Ans: Sprain will occur.

Q16: What are blood platelets?
Ans: Blood platelets are minute (about 2 to 4 μm in diameter), anucleated, disc like bodies. The main function of platelets is to help in clotting of blood.

Q17: What is basement membrane?
Ans: It is very thin non-cellular membrane on which cells of epithelial tissue rest. It also separates the epithelial tissue from the underlying tissues.

Q18: Write the main functions of collenchyma?
Ans: The main functions of collenchyma are to provide mechanical support, tensile strength, elasticity and flexibility to stem, leaf stalks and leaves.

Q19: Where is chlorenchyma tissue present?
Ans: It is present in the centre of stems and roots. If it has chlorophyll then it is called chlorenchyma. It is present in green leaves.

Q20: Mention the functions of cuboidal epithelium.
Ans:
(i) Absorption
(ii) Excretion
(iii) Secretion
(iv) Mechanical support

Q21: Mention the different types of blood cells.
Ans:
(i) WBCs
(ii) RBCs
(iii) Platelets

Q22: Why does the growth of plants occur only in certain specific regions?
Ans: Growth of plants occurs only in certain specific region because the meristematic tissue is located only at these points.

Q23: Define differentiation.
Ans: The process of taking up permanent size, shape and function of cell is called differentiation.

Q24: Name the two types of tissues.
Ans:
(i) Animal tissues
(ii) Plant tissues

Q25: What is the location of stratified squamous epithelium? Also, mention its functions.
Ans: Stratified squamous epitheliums are found in the skin. They are present in layers to prevent wear and tear.