Class 9 Science

Tissue

Exercise Question Answer

Question 1: Define the term tissue.

Answer: A group of cells which is meant to perform a specific function is called tissue.

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

Answer: Xylem is composed of these elements: tracheids, xylem vessel, xylem parenchyma and xylem fibre.

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

Answer: Simple tissues are composed of similar cells, while complex tissues are composed of different types of cells.

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

Answer:

ParenchymaCollenchymaSclerenchyma
Cell wall is thin.Cells wall is thickened at corners.Cell wall is thickened all around.

Question 5: What are the functions of the stomata?

Answer: Functions of stomata are as follows: exchange of gase, and transpiration

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

Answer:

Striated Muscle Smooth Muscle Cardiac Muscle

Question 7: What is the specific function of the cardiac muscle?

Answer: Cardiac muscles facilitate contraction and relaxation of heart; which results in pumping action of the heart.

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

Answer:

Striated MusclesUnstriated MusclesCardiac Muscles
Unbranched fibres; with striations.Unbranched fibres; with striations.Branched fibres with striations.
Present in voluntary organs.Present in involuntary organs.Present in the heart.

Question 9: Draw a labelled diagram of a neuron.

Answer

neuron

Question 10: Name the following:

  1. Tissue that forms the inner lining of our mouth.
  2. Tissue that connects muscle to bone in humans.
  3. Tissue that transports food in plants.
  4. Tissue that stores fat in our body.
  5. Connective tissue with a fluid matrix.
  6. Tissue present in the brain.

Answer: (a)Simple epithelium, (b) Tendon, (c) Phloem, (d) Adipose tissue, (e) Blood, (f) Nervous tissue

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

Answer: Skin: Epithelium, Bark of tree: Epidermis, Bone: Connective tissue, Lining of kidney tubule: Cuboidal Epithelium, Vascular bundle: Complex plant tissue

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

Answer: Parenchyma is present in mesophyll of leaves, fruits, flowers and young stem.

Question 13: What is the role of epidermis in plants?

Answer: Epidermis in plants provides protective covering to the underlying tissues. In xerophytes, epidermis has a waxy coating which prevents water loss.

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

Answer: Cork forms an impervious layer over underlying tissues. Cork prevents entry of water to the underlying tissue.

In Text Questions

Question 1: What is a tissue?

Answer: A group of cells which is meant to serve a special function is called tissue.

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

Answer: Tissues facilitate division of labour. Different tissues are responsible for different functions, which is important for the functioning of a multicellular organism.

Question 3: Name types of simple tissues.

Answer: Simple tissues are as follows:

  1. Parenchyma
  2. Collenchyma
  3. Sclerenchyma

Question 4: Where is apical meristem found?

Answer: Apical meristem is found at root apex, shoot apex, leaf buds, etc.

Question 5: Which tissue makes up the husk of coconut?

Answer: Sclerenchyma

Question 6: What are the constituents of phloem?

Answer: Phloem is composed of sieve tubes, companion cells, phloem fibres and phloem parenchyma.

Question 7: Name the tissue responsible for movement in our body.

Answer: Muscular tissue

Question 8: What does a neuron look like?

Answer: Neuron looks like a star-shaped cell with a tail.

Question 9: Give three features of cardiac muscle.

Answer: Three features of cardiac muscle are as follows:

  1. Cells are branched fibres.
  2. Striations are present on cells.
  3. Cells are capable of continuous contraction and relaxation.

Matter in Our Surroundings

Anything that has both mass and volume is called matter. You can also say that anything which has mass and which occupies space is called matter.

Is Matter Around Us Pure?

Elements and compounds are pure substances. All other substances are mixtures which means they are not pure substances.

Atoms and Molecules

Read about law of conservation of mass, law of constant proportions and Dalton's atomic theory.

Structure of Atoms

Atom is made of three particles; electron, proton and neutron. These particles are called fundamental particles of an atom or sub atomic particles.

Cell: The Fundamental Unit of Life

A cell is capable of independent existence and can carry out all the functions which are necessary for a living being.

Tissue

A groups of cells which is meant for a specific task is called tissue. Tissues are the first step towards division of labour in complex organisms.

Diversity in Living Organisms

Without proper classification, it would be impossible to study millions of organisms which exist on this earth.

Motion

If an object changes its position with respect to a reference point with elapse of time, the object is said to be in motion.

Force & Laws of Motion

Force has numerous effects. Force can set a stationary body in motion. Force can stop a moving body.

Gravitation

Earth attracts everything towards it by an unseen force of attraction. This force of attraction is known as gravitation or gravitation pull.

Work & Energy

When force is exerted on an object and object is displaced, work is said to be done. It means work is the product of force and displacement.

Sound

Sound is a type of energy. Sound travels in the form of wave from one place to another.

Why Do We Fall Ill

Health is a state of physical, mental and social well being. A condition in which the affected person is unable to carry out normal activities is termed as disease.

Natural Resources

Resources which are obtained from nature are called natural resources. Examples: Air, water, soil, wood, etc.

Improvement in Food Production

Food security is said to exist when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life.