GSEB Class 9 Science Solutions Chapter 6 Tissues

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Question 1. What is a tissue?
Answer: A collection of cells that have a similar structure or perform the same particular job together forms a tissue.
In simple words: A tissue is a group of cells that look similar and work together to do one specific job.

Exam Tip: Remember to include both structural similarity and functional coordination in your definition of a tissue to score full marks.

 

Question 2. What is the utility of tissues in multicellular organisms?
Answer: Multicellular organisms exhibit a division of work. In these organisms, various cell types are specialized to create tissues that carry out a particular function. This assists in performing different functions more effectively because each tissue is designed for a specific task.
In simple words: Tissues in multicellular organisms help different cells specialize in specific jobs, making the body work much more effectively and completing tasks efficiently.

Exam Tip: Focus on "division of labor" and "efficiency" as key terms when explaining the utility of tissues in complex organisms.

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Question 3. Name types of simple tissues.
Answer: In plants, there are three main kinds of simple tissues: Parenchyma, Collenchyma, and Sclerenchyma.
In simple words: The basic types of plant tissues are Parenchyma, Collenchyma, and Sclerenchyma.

Exam Tip: When asked to name types, make sure to list all relevant categories mentioned in the context, such as the three simple plant tissues.

 

Question 4. Where is apical meristem found?
Answer: The apical meristem is located at the very end of a plant's root and shoot.
In simple words: You can find apical meristem at the tips of plant roots and shoots.

Exam Tip: Remember that "apical" refers to the apex or tip, which helps recall its location at the growing ends of plants.

 

Question 5. Which tissue makes up the husk of coconut?
Answer: The outer protective layer of a coconut is formed by sclerenchymatous tissue.
In simple words: Sclerenchymatous tissue creates the tough husk of a coconut.

Exam Tip: Associate sclerenchyma with hard, protective structures in plants, like fruit husks or seed coats.

 

Question 6. What are the constituents of phloem?
Answer: Phloem consists of four main kinds of parts:
(a) sieve tubes
(b) companion cells
(c) phloem parenchyma
(d) phloem fibres.
In simple words: Phloem is made of four things: sieve tubes, companion cells, phloem parenchyma, and phloem fibres.

Exam Tip: Be sure to list all four components of phloem accurately, as missing any might result in lost marks.

 

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Question 7. Name the tissue responsible for movement in our body.
Answer: In our bodies, muscular tissue helps with all kinds of movement.
In simple words: Muscular tissue is what allows our body to move.

Exam Tip: Remember that muscular tissue is composed of muscle cells designed for contraction, which drives movement.

 

Question 8. What does a neuron look like?
Answer: A neuron is the basic part of our nervous system. Each neuron possesses three main sections: dendrites, a cell body, and an axon.
In simple words: A neuron is the main cell of the nervous system, having dendrites, a cell body, and an axon.

Exam Tip: When describing a neuron, always mention its three key structural components: dendrites, cell body, and axon.

 

Question 9. Give three features of cardiac muscles.
Answer: The three main features of cardiac muscles are:

• They appear striped, are shaped like cylinders, branch out, and contain a single nucleus.
• These muscles work automatically, meaning they do not move according to our conscious decision.
• They continuously contract and relax in a steady, repetitive pattern.

In simple words: Cardiac muscles are striped, cylindrical, branched, have one nucleus, work without us thinking about it, and beat rhythmically.

Exam Tip: Focus on involuntary nature, striations, and rhythmic action as the main distinguishing features of cardiac muscle.

 

Question 10. What are the functions of areolar tissue?
Answer: Areolar connective tissue is found between the skin and muscles, around blood vessels and nerves, and in the bone marrow. Its functions are to:

• It fills the empty spaces within organs.
• It provides support to the body's inner organs.
• It aids in fixing damaged tissues.

In simple words: Areolar tissue fills gaps, supports organs, and helps repair damaged parts of the body.

Exam Tip: Remember areolar tissue's role as a "packaging tissue" that holds structures in place and assists with repair.

In-Text Activities Solved

(Textbook Page 69)

 

Activity 6.1
Answer:

• The onion in Jar 1 grew longer roots because its root tips allow them to continue extending.
• No, the roots stopped growing once their tips were removed (as seen in the onion placed in jar 2).
• The apical meristem, which helps roots grow, is found at the tips. Therefore, roots cannot grow if their tips are removed.

In simple words: The onion in Jar 1 grew roots because its tips were there; the onion in Jar 2 did not grow roots because its tips were removed, proving that apical meristem at the tips is needed for root growth.

Exam Tip: When explaining experiments, clearly state the observation, compare the results, and provide the scientific reason for the difference.

(Textbook Page 70)

 

Activity 6.2
Answer:

• No, not all cells have the same basic structure.
• Around eight distinct cell types are visible.
• Different kinds of cells exist because they fulfill various roles within plants.

Meristematic cells divide quickly to create new cells, some of which change to perform a particular job and become part of a permanent tissue. The cells created in this way carry out specific tasks, for instance: parenchymatous cells assist in storing food and photosynthesis; collenchymatous and sclerenchymatous cells offer structural help to different areas of the plant; xylem and phloem respectively transport water and food to various parts of the plant. So, many cell types are necessary to perform the diverse plant functions effectively.
In simple words: Not all plant cells are the same; they specialize. Meristematic cells divide to make new cells, which then become specialized to do different jobs like storing food, providing support, or moving water and food around the plant.

Exam Tip: Emphasize the concept of cell differentiation and specialization as the reason for diverse cell types and their efficient functions in plants.

 

Activity 6.3
Answer: We can see that the plant's outer layer consists of a single sheet of nearly rectangular, tightly packed cells. This particular layer is known as the epidermis. Tiny pores, called stomata, can be seen on the leaf's epidermis. The appearance observed will be as shown next.
In simple words: We observe the epidermis as the outer layer of tightly packed cells with small pores called stomata, which will appear as shown in the diagram.

Guard cells and epidermal cells: (a) lateral view, (b) surface view

Exam Tip: When describing microscopic observations, be precise about cell shape, arrangement, and specific structures like stomata.

Gujarat Board Class 9 Science Tissues Textbook Questions and Answers

 

Question 1. Define the term "tissue".
Answer: A collection of cells that have a similar structure or work together to achieve a specific job forms a tissue.
In simple words: A tissue is a group of cells that are alike and work together to do one job.

Exam Tip: Always include both 'similar cells' and 'specific function' in your definition of a tissue.

 

Question 2. How many types of elements together make up the xylem tissue? Name them.
Answer: Xylem is made up of four main parts:
(a) tracheids
(b) vessels
(c) xylem parenchyma
(d) xylem fibres.
In simple words: Xylem tissue contains four kinds of elements: tracheids, vessels, xylem parenchyma, and xylem fibres.

Exam Tip: Clearly list all four components of xylem and ensure correct spelling to avoid losing marks.

 

Question 3. How are simple tissues different from complex tissues in plants?
Answer: Simple tissues are composed of just one type of cell. These include three main kinds: parenchyma, collenchyma, and sclerenchyma. Complex tissues, on the other hand, are formed from more than one cell type. The transport tissues, known as xylem and phloem, are examples of complex tissues.
In simple words: Simple tissues use only one cell type (like parenchyma), while complex tissues use many cell types (like xylem and phloem).

Exam Tip: Highlight the number of cell types (one vs. multiple) as the primary distinction and provide examples for each.

 

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

In simple words: Parenchyma has thin cellulose walls, collenchyma has thicker cellulose walls at corners, and sclerenchyma has very thick walls due to lignin.

Exam Tip: When differentiating, use clear, concise points for each category and focus specifically on the requested basis, which is the cell wall in this case.

 

Question 5. What are the functions of the stomata?
Answer: Stomata perform the following functions in the plants:

• They allow gases, such as carbon dioxide and oxygen, to move in and out from the atmosphere.
• They also release water as vapor through a process known as transpiration.

In simple words: Stomata help plants breathe by exchanging gases and also release excess water into the air.

Exam Tip: Clearly state both gas exchange and transpiration as the two primary functions of stomata.

 

Question 6. Diagrammatically show the difference between the three types of muscle fibres.
Answer: See the diagram below for a visual representation of the three types of muscle fibres.
In simple words: The diagram illustrates the visual differences among skeletal, smooth, and cardiac muscle tissues.

Muscle tissue: (a) skeletal (striated) muscle tissue (b) smooth muscle tissue (c) cardiac muscle tissue

Exam Tip: For diagrams, ensure labels are accurate and clear, and highlight key distinguishing features such as striations, branching, and nucleus position.

 

Question 7. What is the specific function of the cardiac muscle?
Answer: Cardiac muscles are the specific muscles found in the heart, and they perform rhythmic contractions and relaxations continuously throughout a person's life.
In simple words: Cardiac muscles make the heart beat rhythmically and automatically for a person's entire life.

Exam Tip: The key phrases for cardiac muscle function are "rhythmic contraction and relaxation" and "throughout life" (involuntary, continuous action).

 

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

In simple words: Striated muscles are long, cylindrical, voluntary, and found in limbs; unstriated muscles are spindle-shaped, involuntary, and in internal organs; cardiac muscles are cylindrical, branched, involuntary, and found only in the heart.

Exam Tip: When differentiating, create a clear table with consistent criteria (structure, location) for each muscle type and focus on their unique characteristics.

 

Question 9. Draw a labelled diagram of a neuron. Answer: Nucleus
Answer: The diagram below illustrates the structure of a neuron with its key components, including the nucleus.
In simple words: The diagram displays a neuron, showing its main parts like the nucleus, dendrites, cell body, and axon.

Structure of Neuron

Exam Tip: When drawing, accurately label all major parts of the neuron, including the nucleus, dendrites, cell body, and axon, to ensure full credit.

 

Question 10. Name the following.
(a) Tissue that forms the inner lining of our mouth.
(b) Tissue that connects muscle to bone in humerus.
(c) Tissue that transports food in plants.
(d) Tissue that stores fat in our body.
(e) Connective tissue with a fluid matrix.
(f) Tissue present in the brain.
Answer:
(a) Squamous epithelium
(b) Tendon
(c) Phloem
(d) Adipose tissue
(e) Blood
(f) Nervous tissue
In simple words: The answers are squamous epithelium for mouth lining, tendon for muscle-to-bone connection, phloem for plant food transport, adipose for fat storage, blood as fluid connective tissue, and nervous tissue in the brain.

Exam Tip: For "Name the following" questions, provide concise and accurate single-word or short phrase answers for each part.

 

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

• Skin: Epithelial tissue (Stratified squamous epithelium)
• Bark of tree: Cork
• Bone: Connective tissue (skeletal tissue)
• Lining of kidney tubule: Cuboidal epithelium
• Vascular bundle: Complex permanent tissue

In simple words: The tissues are: skin-epithelial, bark-cork, bone-connective, kidney lining-cuboidal epithelium, and vascular bundle-complex permanent tissue.

Exam Tip: Be precise with your tissue identification, specifying the sub-type where appropriate (e.g., "stratified squamous epithelium" for skin).

 

Question 12. Name the regions in which parenchyma tissue is present.
Answer: Parenchyma tissue can be found in the mesophyll layer of leaves, and also in the cortex and central pith of stems and roots.
In simple words: Parenchyma is found in leaf mesophyll, and in the cortex and pith of plant stems and roots.

Exam Tip: List all relevant anatomical locations where parenchyma is typically found for a comprehensive answer.

 

Question 13. What is the role of epidermis in plants?
Answer: The epidermis is the outermost layer of cells that covers an organism. It usually consists of a single cell layer and offers protection. In some plants found in dry environments, the epidermis can be thicker or often produce a waxy, water-resistant coating called cutin (a chemical with water-repellent qualities) to stop water from escaping. The stomata, found on the epidermis of leaves, assist in exchanging gases and releasing water vapor through transpiration. Root epidermal cells have root hairs that significantly expand the roots' total surface area for soaking up water.
In simple words: The epidermis protects the plant, prevents water loss (especially with cutin), allows gas exchange through stomata, and root hairs help absorb water.

Exam Tip: When discussing the epidermis, cover its protective role, adaptations for dry habitats, and specialized structures like stomata and root hairs for a complete explanation.

 

Question 14. How does the cork act as a protective tissue?
Answer: Cork cells are dead and tightly packed together, lacking any gaps between them. Their walls contain a chemical named suberin, which prevents gases and water from passing through. These qualities enable cork to function as a protective tissue.
In simple words: Cork cells are dead and tightly packed, with suberin in their walls, making them waterproof and gasproof, thus protecting the plant.

Exam Tip: Key points for cork's protection are its dead, compact cells, lack of intercellular spaces, and the presence of suberin making it impermeable.

 

Question 15. Complete the table:
Answer: Permanent tissues are categorized into two main types: Simple tissues, which include Parenchyma, Collenchyma, and Sclerenchyma; and Complex tissues, which consist of Xylem and Phloem.
In simple words: Permanent tissues are divided into simple (Parenchyma, Collenchyma, Sclerenchyma) and complex (Xylem, Phloem) types.

Exam Tip: Ensure you accurately list all the specific tissue types under their correct categories (simple vs. complex permanent tissues).