Selina Concise Solutions for ICSE Class 9 Biology Chapter 3 Tissues Plant And Animal Tissues

Exercise 1

Question A:
Answer: 1. (c) Parenchyma
2. (a) Fibrous connective tissue
3. (a) Meristem- Actively dividing cells
These answers identify the primary types of tissues found in plants and animals based on their specific functions. For example, meristematic tissues are responsible for the continuous growth of a plant throughout its life.
Teacher's Tip: Think of "Meristem" like a "Merry-go-round" that never stops spinning or "dividing."
Exam Tip: Always write the option letter and the text together to avoid any confusion for the examiner.

Question B.1:
Answer: (a) Apical or terminal meristematic tissue
(b) Protective tissue
(c) Columnar epithelium (Epithelial tissue)
(d) Ligament (Connective tissue)
(e) Conducting tissue
(f) Sclerenchyma (Supporting tissue)
These names represent the specialized roles that different groups of cells play within an organism. Identifying them correctly is the first step toward understanding how complex life forms manage different biological processes.
Teacher's Tip: Use the word "Conducting" to remember tissues that move things, like a conductor moves a train.
Exam Tip: If the question asks to "name the tissue," providing the general type (e.g., Connective tissue) along with the specific name (e.g., Ligament) is best.

Question B.2:
Answer: Sclerenchyma composed of long, narrow and thick cells, which have become dead, forms the least specialized tissue in plants. This tissue forms the walls and boundaries of plant cells and provides strength to tissue plant parts.
This tissue acts as the structural support for the plant, much like a skeleton does for humans. Because the cells are dead and have thick walls, they provide a very rigid and tough protective layer.
Teacher's Tip: Think of the hard shell of a walnut; that is made of sclerenchyma!
Exam Tip: Mentioning that sclerenchyma cells are "dead" at maturity is a key point for scoring full marks.

Question B.3:
Answer: (a) Tissue
(b) Permanent tissue cells
(c) Cambium
These terms are essential for describing how plants grow and mature. Cambium, for instance, is the layer in a tree trunk that allows it to grow wider each year.
Teacher's Tip: Remember: Meristematic cells eventually "settle down" and become Permanent tissue.
Exam Tip: When providing scientific terms, double-check your spelling to ensure no marks are lost on technical words.

Question B.4:
Answer: (a) Tips of roots
(b) Nose
(c) Lining of mouth
(d) Veins of leaves
(e) Lining of trachea
(f) Bones
Knowing the location of tissues helps us understand why they are shaped the way they are. For example, the lining of the mouth must be thin and moist, while bones must be hard and dense for support.
Teacher's Tip: Root "Tips" are where the "Action" is—that's where the plant grows into the soil.
Exam Tip: When asked for a location, be specific (e.g., "Tips of roots" instead of just "Roots").

Question B.5:
Answer: (a) Squamous epithelium
(b) Cuboidal epithelium
(c) Neuron
(d) Ciliated columnar epithelium
Animal tissues are categorized by their shape and structure, which dictates their function. A "Neuron," or nerve cell, is specialized to carry electrical signals, while epithelium covers and protects surfaces.
Teacher's Tip: "Squamous" sounds like "Squashed"—these are flat, thin cells!
Exam Tip: Identify epithelial tissues by their shapes (cube-shaped = cuboidal, column-shaped = columnar).

Question C.1:
Answer: Ciliated columnar epithelium is found in the lining of trachea. This epithelium has thread-like projections called cilia at their free ends. The cilia constantly keep lashing and move the materials which enter this organ.
The cilia act like tiny brushes that sweep away dust and mucus to keep our breathing passages clean. This continuous movement helps protect our lungs from irritation and infection.
Teacher's Tip: Think of cilia as the "broom bristles" of your windpipe.
Exam Tip: Always describe the function (moving materials) alongside the structure (thread-like projections).

Question C.2:
Answer: Nervous tissue or neurons are specialized group of cells. This tissue is concerned with perception and responses of animals. The nervous tissue constitutes the nervous system, which is an organ system. It controls and coordinates all the systems of the body.
Nervous tissue acts as the communication network for the body, sending and receiving signals from the brain. It is what allows us to feel pain, see light, and move our muscles instantly.
Teacher's Tip: Imagine the nervous system as the "internet" of your body, connecting everything together.
Exam Tip: Use the words "control" and "coordinate" together to describe the function of nervous tissue perfectly.

Question C.3:
Answer: 1. Muscular tissue (Cardiac muscles)
2. Epithelial tissue (Lining of blood vessels of the heart)
3. Connective tissue (Fluid connective tissue in the form of red blood corpuscles)
The heart is a complex organ made of multiple tissue types working together to pump blood. While muscles do the actual pumping, connective tissues transport the vital nutrients throughout the body.
Teacher's Tip: The heart is "Muscle with a Mission"—it never gets tired because of its unique cardiac tissue.
Exam Tip: When listing tissues in an organ, mention the specific name (like Cardiac) for a complete answer.

Question C.4:
Answer: A tissue is a group of similar cells from the same origin that together carry out a specific function. An egg is a zygote or a cell but a cluster of eggs cannot be considered as a tissue as it does not form an organ like a tissue. Instead it gives rise to a new individual organism if gets fertilised.
To be a tissue, cells must be connected and work as one unit for a single purpose. A group of eggs are separate individuals, not part of a larger structure like a muscle or skin layer.
Teacher's Tip: Remember: Cells make Tissues, Tissues make Organs. Eggs skip the "Tissue" step and go straight to "Organism."
Exam Tip: Include the definition of tissue in your explanation to justify why a cluster of eggs doesn't count.

Question C.5:
Answer: 1. Striated muscles: Provide the force for locomotion and all voluntary movements of the body. These muscles are found in the limbs.
2. Unstriated muscles: Provide movements for the passage of food in the intestines. These muscles are found in iris of the eye, lining of blood vessels, urinary bladder, etc.
3. Cardiac muscles: Provide rhythmic contraction and relaxation movements. These muscles are found only in the heart.
These three muscle types allow for different kinds of movement, from walking to digesting food. Cardiac muscle is special because it works automatically and never stops for your entire life.
Teacher's Tip: "Striated" means "Striped"—these are the muscles you use for sports and running.
Exam Tip: Distinguish between "voluntary" (things you choose to do) and "involuntary" (things your body does on its own).

Question D.1:
Answer: (a) Cell and tissue
Cell: A cell is the structural and functional unit of all living beings. E.g. epithelial cell
Tissue: A tissue is a group of similar cells which perform a specific function. E.g. nervous tissue

(b) Organ and organism
Organ: Several tissues together contribute to specific functions inside the body and constitute an organ. E.g. stomach
Organism: Several organ systems together constitute the organism. E.g. human being

(c) Organ and organelle
Organ: Several tissues together contribute to specific functions inside the body and constitute an organ. E.g. stomach
Organelle: Parts of the cell that have a definite function in the cell. E.g. mitochondria

(d) Organ and organ system
Organ: Several tissues together contribute to specific functions inside the body and constitute an organ. E.g. stomach
Organ system: Many organs act together to perform a specific life process and constitute an organ system. E.g. digestive system
This hierarchy shows how life is built from the smallest parts (organelles and cells) up to the whole living being. Every level depends on the one below it to function correctly.
Teacher's Tip: Think of it as a ladder: Cell -> Tissue -> Organ -> Organ System -> Organism.
Exam Tip: Always provide an "E.g." (example) for both sides of the comparison to show you understand the hierarchy.

Question D.2:
Answer: (a) Parenchyma and Collenchyma
Parenchyma: (i) Consists of large thin-walled living cells with a single large vacuole. (ii) Intercellular spaces may or may not be present.
Collenchyma: (i) Consists of elongated cells having thickening in their cell walls. (ii) Intercellular spaces are totally absent.

(b) Meristematic tissue and Permanent tissue
Meristematic tissue: (i) Have the capacity to divide. (ii) Do not have intercellular spaces.
Permanent tissue: (i) Have lost the capacity to divide. (ii) Have large intercellular spaces.

(c) Sclerenchyma and Parenchyma
Sclerenchyma: (i) Consist of dead cells. (ii) Have thick cell walls.
Parenchyma: (i) Consist of living cells. (ii) Have thin cell walls.

(d) Cells of involuntary muscle and voluntary muscle
Involuntary muscle: (i) Small and spindle-shaped. (ii) Uninucleate. (iii) Lack stripes or striations. (iv) Found in the walls of the intestine and lining of blood vessels.
Voluntary muscle: (i) Long and cylindrical. (ii) Multinucleate. (iii) Show stripes or striations. (iv) Found in the arms, legs, face and neck.

(e) Fibres of voluntary muscle and cardiac muscle
Voluntary muscle: (i) Long and cylindrical. (ii) Multinucleate. (iii) Under the control of one’s own will or volition. (iv) Found in the arms, legs, face and neck.
Cardiac muscle: (i) Short and branched. (ii) Uninucleate. (iii) Not under the control of one’s own will or volition. (iv) Found in the heart.
Distinguishing between these tissues helps us identify their specific adaptations for survival. For example, voluntary muscles are built for power, while cardiac muscles are built for endurance and constant movement.
Teacher's Tip: "Spindle-shaped" means the cells are thin at the ends and thick in the middle, like a grain of rice.
Exam Tip: For "Distinguish Between" questions, use a comparison of at least two points for every pair.

Question E.1:
Answer: (a) The given diagram is of the phloem tissue because the cells show cellular contents unlike the xylem tissue which contains hollow cells without any cellular contents.
(b)
1 - Sieve cell
2 - Phloem parenchyma cell
3 - Companion cell
4 - Sieve plate
(c) The phloem is a food-conducting tissue and is likely to be found in the leaves and stem of plants to carry the food manufactured in the leaves to various parts of the plant.
(d)
1 - Sieve cells: Help in the transport of food from leaves to storage organs and other parts of the plant.
2 - Phloem parenchyma cells: Storage of starch, fat and other organic food material.
3 - Companion cells: Help in the functioning of the sieve tube cells.
4 - Sieve plate: Perforations in the sieve plates allow water and dissolved organic solutes to flow along the sieve tube.
Phloem is essential for moving sugar, the plant's food, from where it is made in the leaves to where it is needed for growth. Each component of the phloem has a specific job, such as helping with movement or providing storage.
Teacher's Tip: Think: "Phloem" starts with the 'F' sound, just like "Food." Phloem carries food!
Exam Tip: Be ready to label the "Companion cell" as it is usually found right next to the "Sieve cell."

Question E.2:
Answer: (a) The given diagram shows a nerve cell or neuron.
(b)
1 - Dendrites/Dendrons
2 - Axon
3 - Nucleus
4 - Cyton/Perikaryon
5 - Neurolemma
6 - Axon endings
(c) The nerve cell is likely to be found in the nervous system of the human body. The function of the nerve cell is to transmit messages from one part of the body to another. It is associated with perception and responses of animals.
A neuron is the longest cell in the body and acts like a biological electrical wire. Its unique branched structure allows it to connect to many other cells and relay information instantly.
Teacher's Tip: Imagine the "Axon" as a long tail that carries signals away from the main cell body.
Exam Tip: Labeling the direction of the signal (from Dendrites to Axon endings) can show extra understanding.