TISSUES-01 PDF - Gloria High School Biology Notes

GLORIA HIGH SCHOOL GARHSISAI, VIDYAPATINAGAR, DALSINGSARAI, SAMASTIPUR BIHAR-848503 CLASS-9th BIOLOGY NOTES TISSUES CHAPTER-02 Important Topics of Tissues The following are the most impor...

GLORIA HIGH SCHOOL GARHSISAI, VIDYAPATINAGAR, DALSINGSARAI, SAMASTIPUR BIHAR-848503 CLASS-9th BIOLOGY NOTES TISSUES CHAPTER-02 Important Topics of Tissues The following are the most important topics that are covered in details.  Tissues  Plant Tissues  Animal Tissues  Meristematic tissues  Permanent tissues  Differentiation  Apical meristem  Lateral meristem  Intercalary meristem  Simple permanent tissues  Parenchyma  Collenchyma  Sclerenchyma  Complex permanent tissues  Phloem  Xylem  Epithelial Tissues  Nervous Tissue Tissues Tissues are groups of cells that work together to perform a specific function. They are the building blocks of organisms, whether plants or animals. These specialized groups of cells collaborate to carry out particular tasks essential for the organism’s survival and proper functioning. Plant Tissues In plants, tissues are categorized into two main types: meristematic tissues and permanent tissues. Meristematic tissues are responsible for growth and development, as they contain cells that continuously divide to produce new cells. On the other hand, permanent tissues consist of mature cells that have stopped dividing and perform specific functions like photosynthesis, storage, and support. Permanent tissues can be further classified into various types based on their structure and function, such as parenchyma, collenchyma, and sclerenchyma. Animal Tissues In animals, tissues also play crucial roles in maintaining the organism’s structure and function. Unlike plant cells, animal cells lack cell walls, making animal tissues more flexible. There are four primary types of animal tissues: epithelial tissue, connective tissue, muscle tissue, and nervous tissue. Epithelial tissue covers the body surfaces, lines internal organs, and forms glands. Connective tissue supports and connects different body parts, providing structural support and protection. Muscle tissue facilitates movement by contracting and relaxing, while nervous tissue enables communication between different parts of the body through electrical impulses. Understanding tissues is fundamental in comprehending the complex organization and functioning of living organisms. It allows scientists and researchers to explore how cells collaborate to perform various tasks and how disruptions in tissue function can lead to diseases and disorders. Meristematic tissues Meristematic tissues are crucial components of plant growth and development. These tissues are characterized by their rapid cell division, which leads to the formation of new cells and allows the plant to grow. Meristematic tissues are primarily found at the tips of roots and shoots, as well as in regions called meristems. These regions are responsible for the continuous growth of the plant throughout its life cycle. Permanent tissues Permanent tissues, on the other hand, are derived from meristematic tissues and serve various structural and functional roles in the plant. Unlike meristematic tissues, permanent tissues consist of cells that have undergone differentiation and specialization to perform specific functions. These tissues can be further classified into two main types: simple permanent tissues and complex permanent tissues. Simple permanent tissues are composed of similar types of cells that perform a specific function. For example, parenchyma tissue is made up of living cells and serves functions such as photosynthesis, storage, and secretion. Collenchyma tissue provides support to growing plant parts and is composed of elongated cells with thickened cell walls. Complex permanent tissues, on the other hand, consist of different types of cells that work together to perform specialized functions. Xylem and phloem are examples of complex permanent tissues. Xylem is responsible for transporting water and minerals from the roots to the rest of the plant, while phloem transports organic nutrients, such as sugars, from the leaves to other parts of the plant. Differentiation Differentiation is the process by which meristematic tissues undergo changes to become specialized permanent tissues. This process involves the activation of specific genes within the cells, leading to the development of distinct cell types with unique structures and functions. Apical meristem Apical meristems are meristematic tissues located at the tips of roots and shoots. These tissues are responsible for the primary growth of the plant, contributing to increases in height and length. Apical meristems continuously produce new cells that differentiate into various types of permanent tissues, allowing the plant to grow and develop. meristematic tissues play a vital role in plant growth and development by continuously producing new cells, while permanent tissues contribute to the plant’s structural integrity and functionality through specialized cell types and functions. Differentiation and the presence of apical meristems further enhance the plant’s ability to adapt and thrive in its environment. Lateral meristem Lateral meristem is another type of meristematic tissue found along the lateral walls of the stem. Unlike apical meristems, which promote vertical growth, lateral meristems facilitate horizontal growth by increasing the girth or diameter of the stem. They contribute to the overall expansion and branching of the plant. Intercalary meristem Intercalary meristem is located between the nodes of the stem and the base of the leaf. These meristems play a key role in the process of branching, allowing the plant to grow laterally and produce new shoots or branches. Simple permanent tissues Simple permanent tissues consist of a single type of cell and typically serve structural functions within the plant. They include parenchyma, collenchyma, and sclerenchyma tissues. Parenchyma Parenchyma tissues are composed of loosely packed cells with thin cell walls and large intercellular spaces. They are living cells and play roles in support, storage, and photosynthesis. Chlorenchyma and aerenchyma are two types of parenchyma tissues. Collenchyma Collenchyma tissues are characterized by cells with irregularly thickened corners, providing flexibility and support to plant parts. They are living cells and help prevent bending or breaking of stems and leaves. Sclerenchyma Sclerenchyma tissues comprise dead cells with thickened cell walls containing lignin. These tissues provide rigidity and support to plant structures, such as stems, leaves, and seeds. Complex permanent tissues Complex permanent tissues are composed of multiple cell types working together to perform specific functions. Phloem and xylem are examples of complex permanent tissues involved in the transport of nutrients and water throughout the plant. Phloem Phloem consists of sieve tubes, companion cells, phloem parenchyma, and phloem fibers. It transports organic nutrients, such as sugars, in both directions within the plant. Phloem fibers are the only dead cells in the phloem tissue. Xylem Xylem tissue is responsible for conducting water and minerals from the roots to the rest of the plant. It consists of vessels, tracheids, xylem parenchyma, and xylem fibers. These components provide structural support and storage capabilities in addition to their transport functions. Epithelial Tissues Epithelial tissues are one of the four primary types of animal tissues, along with connective, muscular, and nervous tissues. They serve as the protective covering of both the internal and external surfaces of the body, as well as the lining of various organs, cavities, and vessels. The main functions of epithelial tissues include protection, absorption, secretion, and sensation. There are several types of epithelial tissues, each with its own structure and function: Squamous Epithelium: This type of epithelium is composed of thin, flat cells that resemble scales or flattened plates. Squamous epithelial cells are tightly packed and form a smooth, continuous layer. They are well-suited for facilitating the exchange of gases and fluids. Squamous epithelium can be further categorized into simple squamous epithelium, found in areas where filtration or diffusion occurs (such as the lining of blood vessels and air sacs in the lungs), and stratified squamous epithelium, which provides protection against mechanical and chemical stresses (such as the outer layer of the skin). Cuboidal Epithelium: Cuboidal epithelial cells are cube-shaped with a centrally located nucleus. They line the walls of small ducts and tubules in various glands and organs, including the kidney tubules and salivary glands. Cuboidal epithelium is involved in secretion, absorption, and excretion processes. When organized into glands, cuboidal epithelial cells form glandular epithelium, which secretes substances such as enzymes, hormones, and mucus. Columnar Epithelium: Columnar epithelial cells are tall and elongated, with their nuclei typically located near the basal surface. They are found in the lining of the gastrointestinal tract (e.g., stomach, small intestine, and large intestine) and parts of the respiratory and reproductive systems. Columnar epithelium is specialized for absorption, secretion, and protection. In areas where cilia are present on the surface of columnar cells, they form ciliated columnar epithelium, which helps to move mucus and particles along the respiratory tract. Transitional Epithelium: Transitional epithelial cells have a variable appearance and can change shape from cuboidal to squamous under tension. This type of epithelium is found in regions of the body subjected to stretching and recoiling, such as the urinary bladder, ureters, and urethra. Transitional epithelium allows these structures to accommodate fluctuations in volume without rupturing. Nervous Tissue Nervous tissue is a specialized type of animal tissue that forms the nervous system, which includes the brain, spinal cord, and peripheral nerves. It plays a fundamental role in coordinating and regulating bodily functions, as well as processing sensory information, generating responses, and maintaining homeostasis. The main components of nervous tissue are neurons and neuroglial cells (or glial cells), which work together to transmit electrical signals throughout the body and provide support and protection to neurons. Neurons: Neurons, also known as nerve cells, are the functional units of the nervous system. They are specialized for transmitting electrical impulses, or action potentials, over long distances. Neurons consist of three main parts: a. Cell Body (Soma): The cell body contains the nucleus and other organelles essential for the neuron’s metabolic activities. b. Axon: The axon is a long, slender projection that extends from the cell body and conducts electrical impulses away from the cell body to other neurons, muscles, or glands. c. Axon Terminals: At the end of the axon, specialized structures called axon terminals or synaptic terminals transmit signals to other neurons or target cells through synapses, which are junctions between neurons. Neurons can be classified based on their structure and function into sensory neurons, motor neurons, and interneurons. Sensory neurons transmit sensory information from sensory receptors (such as those for touch, temperature, and pain) to the central nervous system (CNS), while motor neurons convey signals from the CNS to muscles and glands to initiate responses. Interneurons, or association neurons, integrate and process information within the CNS. Neuroglial Cells (Glial Cells): Neuroglial cells, or glial cells, are non-neuronal cells that provide structural support, insulation, and nourishment to neurons. They also play critical roles in maintaining the chemical environment of neurons and modulating synaptic transmission. Glial cells include several types, such as astrocytes, oligodendrocytes, microglia, and Schwann cells, each with distinct functions and properties. Overall, nervous tissue is essential for regulating body functions, processing sensory input, coordinating motor responses, and enabling complex cognitive processes such as learning and memory. Dysfunction or damage to nervous tissue can lead to various neurological disorders and impairments in sensory, motor, and cognitive functions.  NCERT SOLUTION OF “TISSUES”. CHAPTER-02 (BIOLOGY) 1. What is a tissue? Solution: A tissue is defined as a cluster of cells that are similar in structure and work together to perform a particular function. These cells are organized to carry out specific tasks within an organism, such as providing support, enabling movement, or transporting nutrients. Tissues are the building blocks of organs and play a crucial role in the overall functioning of living organisms. 2. What is the utility of tissues in multicellular organisms? Solution: In multicellular organisms, tissues provide structural and mechanical strength, allowing the organism to maintain its shape and withstand various forces. Tissues enable the division of labor, where different types of tissues perform specialized functions. This specialization allows for more efficient and effective functioning of the organism, as each tissue type can focus on a specific task, such as movement, nutrient 3. Name the types of simple tissues. Solution: The types of simple tissues are as follows: 1. Parenchyma 2. Collenchyma 3. Sclerenchyma 4. Where is apical meristem found? Solution: In plants, apical meristem is typically found at:  The tip of the shoot  Root of the plant 5. Which tissue makes up the husk of a coconut? Solution: Sclerenchymatous tissue is a type of permanent tissue found in plants, including in the husk of the coconut. This tissue provides structural support and makes the plant parts stiff and hard. The cells of sclerenchyma tissue are dead at maturity, and their cell walls are heavily thickened with lignin, a substance that strengthens the cell walls and makes them resistant to bending and stretching. This characteristic helps in providing mechanical support and protection to the plant. 6. What are the constituents of phloem? Solution: The phloem constitutes of the following four elements, they are: 1. Sieve tube 2. Companion cells 3. Phloem parenchyma 4. Phloem fibres 7. Name the tissue responsible for movement of our body. Solution: Two tissues jointly are responsible for the movement of our body, namely: 1. Muscular tissue 2. Nervous tissue 8. What does a neuron look like? Solution: A neuron, or nerve cell, is composed of a cell body containing a nucleus and cytoplasm. It features a unique structure with a long, thin extension known as an axon, which transmits electrical signals to other cells or neurons. Neurons possess several shorter, branched structures called dendrites, which receive signals from other neurons and convey them towards the cell body. Neurons are remarkable for their varied sizes; some axons can extend up to a meter in length, facilitating communication across considerable distances within the body’s nervous system. 9. Give three features of cardiac muscles. Solution: Cardiac muscles are specialized tissues designed to pump blood throughout the body. They exhibit several distinct features:  Cylindrical Shape: Cardiac muscle cells are cylindrical in shape.  Striated Muscle Fibers: Like skeletal muscles, cardiac muscle fibers have a striped appearance due to the arrangement of contractile proteins.  Uninucleated and Branched: Each cardiac muscle cell has a single nucleus and often branches to connect with neighboring cells.  Involuntary Nature: Contractions of cardiac muscles are involuntary, meaning they occur without conscious control, ensuring continuous pumping of blood throughout the body. 10. What is areolar tissue? Solution: Areolar tissue is a type of connective tissue commonly found in animals.  Location: Areolar tissue is located between the skin and muscles, around blood vessels and nerves, and within organs such as the bone marrow.  Function: It fills the spaces inside organs, providing support to delicate structures and facilitating tissue repair in case of damage.  Structure: Areolar tissue is characterized by its loose arrangement of collagen and elastin fibers, which give it flexibility and resilience. Page: 78 1. Define the term ’tissue’. Solution: A tissue is a group of cells that are similar in structure and work together to perform a specific function in an organism. These cells are organized to perform specialized tasks that contribute to the overall function and health of the organism. Tissues can be found in plants and animals, where they play essential roles in maintaining structure, providing support, and facilitating various physiological processes necessary for survival. 2. How many types of elements together make up the xylem tissue? Name them. Solution: The xylem tissue in plants is composed of four main elements:  Vessels: These are elongated cells aligned end-to-end, forming continuous tubes for water and mineral transport.   Tracheids: Similar to vessels but narrower and with tapered ends, tracheids also transport water and provide structural support.  Xylem Fibers: These cells are long and slender, providing mechanical support to the plant.  Xylem Parenchyma: These are living cells that store starch, oils, and other substances, and also facilitate lateral movement of water and nutrients. 3. How are simple tissues different from complex tissues in plants? Solution: The following are the differences:  Simple tissues: These are composed of a single type of cell that performs a specific function. Examples include parenchyma, collenchyma, and sclerenchyma in plants, each serving roles like storage, support, or protection.  Complex tissues: These involve multiple types of cells working together to perform specialized functions. For instance, xylem and phloem in plants coordinate to transport water, nutrients, and organic substances throughout the plant. 4. Differentiate between parenchyma, collenchyma and sclerenchyma on the basis of their cell wall. Solution: The following are the differences between different tissues based on cell wall: Parenchyma:  Cell walls are thin and primarily made up of cellulose.  These tissues are often involved in functions like photosynthesis, storage, and secretion. Collenchyma:  Cell walls are thicker at the corners due to the deposition of pectin.  They provide flexible structural support to young parts of the plant, such as stems and petioles. Sclerenchyma:  Cell walls are very thick due to the deposition of lignin, making them rigid and strong.  These tissues provide mechanical support and protection to mature parts of the plant, such as the seed coats and vascular bundles. 5. What are the functions of the stomata? Solution: Stomata are small pores found on the outer layer (epidermis) of leaves and stems of plants. They play several important roles:   Gas Exchange: Stomata allow for the exchange of gases, such as oxygen and carbon dioxide, between the plant and its environment. This process is crucial for photosynthesis (uptake of carbon dioxide) and respiration (release of oxygen).  Transpiration: Stomata also regulate the process of transpiration, where water vapor exits the plant through these pores. This helps in cooling the plant and maintaining its internal water balance. 6. Show the difference between the three types of muscle fibres diagrammatically. Solution: There are three types of muscle fibres, they are: 1. Cardiac muscles  Present in the heart.  Involuntary in nature.  They have 1 nucleus.  The muscle fibers are branched. 2. Smooth muscles  Found in lungs and alimentary canal.  Involuntary in nature.  They have 1 nucleus.  They are spindle-shaped. 3. Striated muscles  They are connected with bones  Voluntary in nature.  They are long and cylindrical muscle fibers.  They possess many nuclei.  Striated muscles are unbranched. 7. What is the specific function of the cardiac muscle? Solution: Cardiac muscles are characterized by their branched and cylindrical shape. They are uninucleated and function involuntarily, meaning they contract and relax rhythmically throughout an individual’s lifetime. These muscles are essential for maintaining the continuous pumping action of the heart, which circulates blood throughout the body, supplying oxygen and nutrients to tissues and organs while removing metabolic waste products. 8. Complete the following chart. Solution: The completed chart is as follows:  SOME IMPORTANT MCQS 1. Vertical growth in plants takes place by: (a) Lateral meristem (b) Apical meristem (c) Intercalary meristem (d) None of the above Ans: (b) Apical meristem. 2. Which of these components of blood fight infection? (a) RBC (b) WBC (c) Platelets (d) Serum Ans: (b) WBC. 3. In desert plants, the rate of water loss gets reduced due to the presence of: (a) Cuticle (b) Stomata (c) Lignin (d) Suberin Ans: (a) Cuticle. 4. Cartilage is not found in: (a) Nose (b) Ear (c) Kidney (d) Larynx Ans: (c) Kidney. 5. Which of these types of cells is most likely to divide? (a) Epidermis (b) Parenchyma (c) Meristem (d) Xylem Ans: (c) Meristem. 6. Companion cells are associated with: (a) Sieve tubes (b) Sclerenchyma (c) Vessels (d) Parenchyma Ans: (a) Sieve tubes. 7. Which tissue has chloroplast in cells? (a) Parenchyma (b) Chlorenchyma (c) Sclerenchyma (d) Aerenchyma Ans: (b) Chlorenchyma. 8. Intestine absorbs digested food materials. What type of epithelial tissue is responsible for that? (a) Stratified squamous epithelium (b) Columnar epithelium (c) Pseudostratified epithelium (d) Cuboidal epithelium Ans: (b) Columnar epithelium. 9. Lysosomes are called suicide bags because a. It causes the cell to break its cell membrane, causing death b. It kills the surrounding cells by releasing enzymes c. The enzymes are capable of digesting cells d. All of the above e. None of the above Ans: d. All of the above 10. One of the following is not true about Cardiac muscles a. They can be controlled b. They lack mitochondria c. Cells are bi-nucleate d. Found outside the heart such as the digestive tract e. All of the above Ans: e. All of the above 11. ________ is not found in xylem tissues. a. Sieve tubes b. Xylem parenchyma c. Tracheids d. Vessels e. None of the above Ans: a. Sieve tubes 12. One of the following is not a function of the stomata a. Directly participates in the process of photosynthesis b. Helps with the exchange of gases c. Helps to create water pressure, forcing water upward d. All of the above e. None of the above Ans: a. Directly participates in the process of photosynthesis 13. Which of the following statements are correct about meristematic tissues? a. Composed of cells that are incapable of cell division b. Composed of a single type of cell c. It is composed of cells that are able to perform cell division d. All the above e. None of the above Ans: c. It is composed of cells that are able to perform cell division 14. Which of the following is connective tissue? a. Ligament b. Tendon c. Blood d. All of the above e. None of the above Ans: d. All of the above 15. __________ are cemented to one another, forming an irregular layer. These form the outer protective layer of the skin in an animal’s body. a. Connective tissue b. Muscular tissues c. Nervous tissues d. Compound epithelium cells e. None of the above Ans: d. Compound epithelium cells 16. Rapid elongation of a bamboo stem is due to a. Lateral meristem b. Intercalary meristem c. Apical meristem d. Cambium e. None of the above Ans: b. Intercalary meristem 17. The function of dismantling and recycling in a cell is undertaken by a. Nucleus b. Chromosomes c. Lysosomes d. Mitochondria e. None of the above Ans: c. Lysosomes 18. The Nodes of Ranvier are found in: a. Nerve cells b. Heart cells c. Liver cells d. All of the above e. None of the above Ans: a. Nerve cells  Very Short Answer Questions 1 Marks 1. Where is apical meristem found? Ans: The apical meristem is found in the growing tips of stems and roots in plants. 2. Which tissue makes up the husk of coconut? Ans: Sclerenchyma tissue. 3. What are the constituents of phloem? Ans: Sieve tubes, companion cells, phloem parenchyma and phloem fibers (bast). 4. Name the tissue responsible for movement in our body. Ans: Muscle/muscular tissue. Short Answer Questions (2 Marks) 1. What is a tissue? Ans: A tissue is a group of cells that are similar in origin and structure, specialized to perform a particular function. Tissues function efficiently by grouping cells together. Examples include blood, phloem, and muscle. 2. What are the constituents of phloem? Ans: The five constituents of phloem are sieve cells, sieve tubes, companion cells, phloem parenchyma, and phloem fibers. 3. Name types of simple tissues. Ans: The three types of simple tissues are: i) Parenchyma ii) Collenchyma iii) Sclerenchyma 4. What does a neuron look like? Ans: A neuron consists of a cell body from which long, thin, hair-like parts arise. It has a single long part called an axon and many short, branched parts called dendrites. 5. How many types of elements together make up the xylem tissue? Name them. Ans: Xylem tissue consists of four types of elements: i) Tracheids ii) Vessels iii) Xylem fibers iv) Xylem parenchyma 6. How are simple tissues different from complex tissues in plants? Ans: Simple Tissues: Consist of only one type of cell and work as individual units to perform specific functions. Complex Tissues: Consist of more than one type of cell that work together as a unit to perform a particular function. 7. Differentiate between parenchyma, collenchyma, and sclerenchyma on the basis of their cell wall. Ans: Parenchyma: Thin cell walls made up of cellulose. Collenchyma: Cell walls thickened at the corners, made up of cellulose. Sclerenchyma: Very thick cell walls made up of lignin. 8. What are the functions of stomata? Ans: The functions of stomata are: i) Gaseous exchange with the atmosphere. ii) Transpiration, which involves the removal of excess water through water vapor formation. 9. What is the specific function of the cardiac muscle? Ans: Cardiac muscles are responsible for pumping blood throughout the body by rhythmic contraction and relaxation. They work continuously without fatigue. 10. Name the following: (a) Tissue that forms the inner lining of our mouth. Ans: Epithelial tissue. (b) Tissue that connects muscle to bone in humans. Ans: Tendon. (c) Tissue that transports food in plants. Ans: Phloem. (d) Tissue that stores fat in our body. Ans: Adipose tissue. (e) Connective tissue with a fluid matrix. Ans: Blood. (f) Tissue present in the brain. Ans: Nerve tissue. 11. Identify the type of tissue in the following: skin, bark of tree, bone, lining of kidney tubule, vascular bundle. Ans: Skin: Squamous epithelial tissue. Bark of tree: Epidermal tissue. Bone: Connective tissue. Lining of kidney tubule: Cuboidal epithelial tissue. Vascular bundle: Complex permanent tissue. 12. Name the regions in which parenchyma tissue is present. Ans: Parenchyma tissue is found in soft plant parts such as leaf mesophyll, young stems, roots, leaves, vascular bundles, flowers, and fruits. 13. What is the role of epidermis in plants? Ans: The epidermis acts as a protective layer for all plant parts. It helps prevent water loss, controls gas exchange, and secretes a waxy, water-resistant layer for protection. 14. How does the cork act as a protective tissue? Ans: Cork cells are dead, compactly arranged, and have suberin deposits in their walls, making them hard and impermeable. This protects plants from unfavorable conditions and microbial attacks. 15. What are meristematic and permanent tissue? Ans: Meristematic Tissue: It is a dividing tissue responsible for plant growth, classified as apical, lateral, or intercalary. Permanent Tissue: Formed by meristematic tissue cells that lose their ability to divide, they differentiate into permanent tissues with specific shapes and functions. 16. What is the function of Tendon and ligament? Ans: Ligaments: They connect one bone to another bone and another type of connective tissue. They are strong, elastic, consisting of yellow fibers. Tendon: They connect muscle to bone and another type of connective tissue. They are tough, non – elastic, consisting of white fibres. 17. Draw a well labeled diagram of neuron 18. Differentiate the following activities on the basis of voluntary or involuntary: a) Jumping of frog Ans: Voluntary b) Pumping of the heart Ans: Involuntary c) writing with hand Ans: Voluntary d) Moving of chocolate in stomach Ans: Involuntary 19. Name the following: a) Tissue that stores fats in our body. Ans: Adipose tissue b) Tissue presents in the brain Ans: Nervous tissue c) Connective tissue with fluid matrix. Ans: Blood d) Tissue that connects muscles to bones in humans. Ans: Tendons 20. Write the difference between cartilage and bone: Cartilage Bone Soft and flexible Hard and inflexible Non-porous Porous No blood vessels Blood vessels are present Matrix is made up of protein Matrix is made up of calcium and magnesium salts 21. Which components of xylem are living and which ones are dead? Ans: Xylem is composed of four elements:  Tracheid: Dead  Vessels: Dead  Xylem parenchyma: Living  Xylem fibres: Dead 22. Define due process of differentiation. Ans: Dividing tissue is the reason for growth of plants occurs only in specific regions this is also known as meristematic tissue. The cells formed by meristematic tissue later lose the ability to divide as a result permanent tissue is formed. The process of taking up a permanent shape, size, and a function is called differentiation. 23. Define tissue. What is the utility of tissue in multicellular organisms? Ans: Group of similar cells performing similar functions are called tissue. Millions of cells will be there in multicellular organisms. Specific functions are carried out by different groups of cells. 24. Mention characteristics of permanent tissues. Ans: Characteristics of permanent tissues are:  Cells are large, comparatively thick walls and well developed.  Cytoplasm is present as a layer along the cell wall.  Bigger nucleus, vacuole is present in the cell.  There is lack of the power for the cell division in permanent tissue 25. Mention the functions of nervous tissue. Ans: Function of nervous tissues are:  They conduct nerve impulses from one part of the body to another part.  The nervous tissues in the body are specialised for being stimulated and then pass on the stimulus very quickly from one place to another. 26. Animals of colder regions and fishes of cold water have thick layers of subcutaneous fat. Explain, why? Ans: Thick layer of subcutaneous fat acts as an insulator. It retains heat in animals of colder regions and fishes of cold-water and thus maintains the body temperature. The heat loss will be less when the layer of subcutaneous fat is thicker. 27. Name the two main types of plant tissues. Ans: Plant tissues are mainly divided into two types they are:  Meristematic tissue  Permanent tissue 28. Water hyacinth floats on the water surface. Explain. Ans: Water hyacinth floats on the surface of water due to presence of aerenchyma. It is a special form of parenchyma, which contains air cavities. It provides buoyancy because of the air trapped inside which helps water hyacinth in floating because of the air trapped inside. 29. Name the two types of vascular tissues. Ans: Types of vascular tissues are  Xylem: It conduct water and minerals from roots to the parts of the plant  Phloem: It conduct food from leaves to all parts of plant 30. How many types of elements are present in the phloem? Ans: Four types of elements are present in the phloem:  Sieve tube: Helps in the conduction of food material.  Companion cells: Assist the sieve tube in food conduction.  Phloem parenchyma: Storage function.  Phloem fibers: Provide mechanical support. Short Answer Questions (3 Marks) 31. What is the utility of tissues in multicellular organisms? Ans: In multicellular organisms, tissues enable the division of labor among different cell groups. Specific functions are performed by different types of tissues, allowing complex processes to occur efficiently. For example, the brain controls bodily functions, the heart pumps blood, kidneys filter waste, and sense organs gather information. This specialization is essential for the organism’s survival and proper functioning. 32. Give three features of cardiac muscles. Ans: i. Cardiac muscles are involuntary and operate without conscious control. ii. The cells are cylindrical, branched, striated, and uninucleate. iii. They contract and relax rhythmically. 33. What are the functions of areolar tissue? Ans: Areolar tissue is a connective tissue that performs several functions, including: i) Filling spaces inside organs. ii) Supporting internal organs. iii) Assisting in tissue repair. 34. Diagrammatically show the difference between the three types of muscle fibres. Ans: Muscle Visceral Skeletal Cardiac Fibres Contracts Slowly Rapidly Rapidly Found Viscera, Blood Trunk, Extremities, Head and neck Heart vessels Control Involuntary Voluntary Involuntary 35. Differentiate between striated, unstriated, and cardiac muscles on the basis of their structure and site/location in the body. Ans: Feature Striated Muscles Unstriated Muscles Cardiac Muscles Striations Light and dark bands No striations Striations present present Cell Elongated, cylindrical, Long, spindle-shaped, Cylindrical and Shape unbranched unbranched branched Nuclei Multinucleate Uninucleate Uninucleate Function Voluntary movements Involuntary (walls of Involuntary (heart organs, vessels) contractions) 36. How many types of tissues are found in animals? Name the different types. Ans: Animals have four main types of tissues: (a) Epithelial Tissue: Forms protective coverings. (b) Connective Tissue: Provides support and binds other tissues. (c) Muscular Tissue: Facilitates movement through contraction. (d) Nervous Tissue: Receives, processes, and transmits signals. 37. Differentiate between voluntary and involuntary muscles. Give one example of each. Ans: Feature Voluntary Muscles Involuntary Muscles Location Attached to bones Attached to visceral organs Control Move by conscious will Function without conscious control Cell Long, cylindrical, multinucleate Uninucleate, often spindle-shaped Structure Example Muscles in limbs Heart muscle 38. What are the major functions of blood? Ans: Blood is a connective tissue with several functions: Transports oxygen, nutrients, hormones, and waste products. Regulates body temperature by distributing heat. Protects against disease via white blood cells and aids in wound healing. Contains platelets for blood clotting. 39. Write about the functions of: (a) Epidermis: Provides protection and forms a waterproof barrier to reduce water loss. (b) Cork: Acts as a protective layer, preventing desiccation and injury while also blocking pathogens. (c) Stomata: Small openings on leaves that facilitate gas exchange. 40. Mention the characteristics features of connective tissue. Ans: Connective tissue features include:  Loosely spaced cells embedded in a non-living matrix.  The matrix can be jelly-like, fluid, dense, or rigid.  Its composition varies based on the specific function of the connective tissue. 41. Differentiate between parenchyma and collenchyma Ans: Difference between parenchyma and collenchyma is given below: Parenchyma Collenchyma Thick-walled cells mainly at Thin-walled cells corners Intercellular spaces are sometimes Intercellular spaces are absent present Cells may be in oval, circular or Cells are isodiametric polygonal. 42. Mention the characteristics features of connective tissue. Ans: Characteristics of connective tissue:  The cells are loosely spaced and are embedded in a non – living intercellular matrix  The intercellular matrix may be like jelly, fluid, dense or rigid.  Depending on the connective tissues functions the nature of the matrix varies. 43. How does cardiac muscle differ from both voluntary and involuntary muscles in both structure and function? Ans: Cardiac muscles are the muscles of the heart that pumps blood to all parts of the body and it shows rhythmic contraction and relaxation throughout life without any fatigue. The cells of heart muscles are branched, cylindrical and uninucleate.  Cardiac Muscles are involuntary  More akin in structure and only found in heart.  They function throughout the life 44. Write differences between blood and lymph. Ans: Difference between blood and lymph is listed below: Blood Lymph Colored fluid Colorless fluid Blood consists of RBC, WBC, Lymph mainly consists of plasma Platelets and Plasma and WBC. Lymph is a fluid that surrounds Present in heart, arteries and veins. the body cells. 45. Give reasons for: a) Intercellular spaces are absent in sclerenchyma tissues. Ans: Sclerenchyma cells are closely packed Hence intercellular spaces are absent. Its tissues are dead simple permanent tissues. b) Meristematic cells have a prominent muscle and dense cytoplasm but they lack muscles Ans: Meristematic cells have continuously dividing cells. Cells of meristem are not differentiated. It continuously divides and forms new cells which increase length and girth of the plant body. c) We get crunchy and granular feeling, when we chew pear fruit. Ans: due to presence of stone cells or grit cells, known as sclereids 46. Why is epidermis important for the plants? Ans: Epidermis is the Outer protective covering of plants:  Epidermis is covered with a waterproof coating or layer called cuticle which can reduce water loss.  It also helps in the exchange of gases by the small pores called stomata. 47. Describe different types of meristems. Ans: Based on their location in the plant body, meristems are of three types. a) Apical meristems – Occurs at the growing tips of roots and shoots and brings about an increase in length of the plant b) Lateral meristems – It occurs on the sides almost parallel to the long axis of the root, stem and its branches. Brings about an increase in the width or girth of the stem or root. c) Intercalary meristems – located near to the node. Cells are very active, and have dense cytoplasm and thin cellulose. lack of vacuoles in intercalary meristems. 48. If you are provided with three slides, each containing one types muscles fibres, how will you identify them? Ans: If we are provided with three slides, each containing one types muscles fibres, we can identify them by following points: a) Skeletal muscles or voluntary muscles show alternate light and dark bands under microscope. b) Unstriated muscles or involuntary muscles show no light or dark bands, multinucleate. c) Cardiac muscles fibres show light and dark bands, fibres are interconnected with one or two nuclei. 49. If a potted plant is covered with a glass jar, water vapours appear on the wall of the glass jar. Explain why? Ans: This is because of the process called transpiration. Plants always lose water from the surface of leaves. Water reaches leaves by xylem vessels, where evaporation takes place by stomata. Gaseous exchange and also removal of excess water are performed by the Stomata present in the leaves. 50. Identify the following tissue and mention their function. Ans: A) Parenchyma: stores food , it sometimes contains chlorophyll so performs photosynthesis, after that it is called chlorenchyma, in aquatic plants parenchyma to help them float because of large air cavities. B) Collenchyma: It provides mechanical strength and allows bending of various parts of a plant without breaking. C) Sclerenchyma: Provides strength to the plant parts, makes the plant hard and stiff. 21. Differentiate between meristematic and permanent tissue. Ans: Difference between meristematic and permanent tissue is given below: Meristematic tissue Permanent tissue Cell are small and thin walled Cells are large and mostly thick walled Layer of cytoplasm is present along Cells are rich in cytoplasm the cell wall There won’t be any Presence of intercellular space intercellular space Always living in nature May be living or dead Power of cell division is Power of cell division is absent present  CLASS-9 SCIENCE TEST QUESTIONS CHAPTER 2 - TISSUES MCQ QUESTIONS 1. Which of the following tissues has dead cells? (a) Parenchyma (b) Sclerenchyma (c) Collenchyma (d) Epithelial tissue 2. Find out incorrect sentence (a) Parenchymatous tissues have intercellular spaces (b) Collenchymatous tissues are irregularly thickened at corners (c) Apical and intercalary meristems are permanent tissues (d) Meristematic tissues, in its early stage, lack vacuoles 3. Girth of stem increases due to (a) apical meristem (b) lateral meristem (c) intercalary meristem (d) vertical meristem 4. Which cell does not have a perforated cell wall? (a) Tracheids (b) Companion cells (c) Sieve tubes (d) Vessels 5. Intestine absorb the digested food materials. What type of epithelial cells are responsible for that? (a) Stratified squamous epithelium (b) Columnar epithelium (c) Spindle fibres (d) Cuboidal epithelium 6. A person met with an accident in which two long bones of hand were dislocated. Which among the following may be the possible reason? (a) Tendon break (b) Break of skeletal muscle (c) Ligament break (d) Areolar tissue break 7. While working and running, you move your organs like hands, legs, etc. Which among the following is correct? (a) Smooth muscles contract and pull the ligament to move the bones (b) Smooth muscles contract and pull the tendons to move the bones (c) Skeletal muscles contract and pull the ligament to move the bones (d) Skeletal muscles contract and pull the tendon to move the bones 8. Which muscles act involuntarily? (i) Striated muscles (ii) Smooth muscles (iii) Cardiac muscles (iv) Skeletal muscles (a) (i) and (ii) (b) (ii) and (iii) (c) (iii) and (iv) (d) (i) and (iv) 9. Meristematic tissues in plants are (a) localised and permanent (b) not limited to certain regions (c) localised and dividing cells (d) growing in volume 10. Which is not a function of epidermis? (a) Protection from adverse condition (b) Gaseous exchange (c) Conduction of water (d) Transpiration 11. Select the incorrect sentence (a) Blood has a matrix containing proteins, salts, and hormones (b) Two bones are connected with ligament (c) Tendons are non-fibrous tissue and fragile (d) Cartilage is a form of connective tissue 12. Cartilage is not found in (a) nose (b) ear (c) kidney (d) larynx 13. Fats are stored in the human body as (a) cuboidal epithelium (b) adipose tissue (c) bones (d) cartilage 14. Bone matrix is rich in (a) fluoride and calcium (b) calcium and phosphorus (c) calcium and potassium (d) phosphorus and potassium 15. Contractile proteins are found in (a) bones (b) blood (c) muscles (d) cartilage 16. Voluntary muscles are found in (a) alimentary canal (b) limbs (c) iris of the eye (d) bronchi of lungs ANSWERS 1. (b) 2. (c) 3. (b) 4. (b) 5. (b) 6. (c) 7. (d) 8. (b) 9. (c) 10. (c) 11. (c) 12. (c) 13. (b) 14. (b) 15. (c) 16. (b) Q.1 What is a tissue? (1 Mark) Ans. A group of cells that are similar in origin, structure and function is termed as tissue. Q.2 Name types of simple tissues. (1Mark) Ans.Parenchyma, collenchyma, and sclerenchyma. Q.3 Where is apical meristem found? (1Mark) Ans.Tips of stem and root. Q.4 What are the constituents of phloem? (2Marks) Ans. The constituents of phloem are: (i)Sieve cell and sieve tubes. (ii)Companion cell (iii)Phloem parenchyma (iv)Phloem fibre. Q.5 What does a neuron look like? (1 Mark) Ans. It looks like a long thread having a cell body and axon with nerve endings. Q.6 How many types of elements together make up the xylem tissue? Name them.(2 Marks) Ans. Xylem is made of four types of elements - (i) Trachieds (ii) Vessels (iii) Xylem fibres and (iv) Xylem parenchyma Q.7 What are the functions of stomata? (1 Mark) Ans.(i)Gaseous exchange (ii)Transpiration Q.8 What is the role of epidermis in plants? (3 Marks) Ans. Epidermis plays a protective role. It protects all the external parts of the plant against loss of water, mechanical injury and invasion by parasites, fungi etc. Epidermal cells on the aerial parts of the plant often secrete a waxy fluid protects the plant surface from mechanical injury and water loss. Root hair present on epidermis of root help in absorption of water and mineral from soil. 9. What is the utility of the tissues in multi - cellular organisms? (3Marks) Ans. In unicellular organisms a single cell carries all the functions. But in multi-cellular organisms, each specified function is taken up by a different group of cells called tissue. Multi – cellular organisms show division of labour. Tissues provide protection, and mechanical strength and give efficiency of function to the organism. Q.10 Which tissue makes up the husk of coconut? (1 Mark) Ans.Sclerenchyma (fibres) Q.11Give three features of cardiac muscles. (3 Marks) Ans. (i)Heart (cardiac) muscle cells are cylindrical, branched and un enucleated. (ii)They are involuntary. (iii)They show rhythmic contraction & relaxation throughout life. Q.12 What are the functions of areolar tissue? (3 Marks) Ans. (i)It fills the space inside the organs. (ii)Supports internal organs. (iii)Helps in repair of tissues. Q.13 Differentiate between: a) Simple tissue and complex tissue. b) Parenchyma, collenchyma and sclerenchyma. (5 Marks) Ans. (a) SIMPLE TISSUE COMPLEX TISSUE 1. Simple tissue is a group of one type of 1. Complex tissue is made up of more cells e.g. parenchyma, sclerenchyma and than one type of cells and they work collenchyma together as a unit e.g. xylem & phloem (b) PARENCHYMA COLLENCHYMA Sclerenchyma The cell wall is The cell wall is irregular The walls are thick due to presence without any and thickened at of lignin. Often the thickening is so thickening. corners. much that there is no internal space inside the cell. Q.14 Draw a labelled diagram of a neuron. ( 2 Marks) Q.15 Name the meristematic tissue, which increases the thickness of plants. (1Mark) Ans.Cambium (lateral meristem) Q.16 What is middle lamella? (1 Mark) Ans. A wall between adjacent plant cells is known as the middle lamella. Q.17 What are the other names of striated muscles? (1 Mark) Ans. Skeletal and voluntary muscles. Q.18 Give example of a cartilaginous bone in our body. (1 Mark) Ans. Nose and ear pinna. Q.19 How many types of tissues are found in animals? (2 Marks) Ans. Four types of tissues are found in animals: (i)Epithelial (ii)Muscular(iii)Connective(iv)Nervous Q.20 What is the composition of blood? (2 Marks) Ans. Blood comprises of a liquid matrix also called plasma in which following types of blood cells are found - RBC(Red Blood Corpuscles) WBC(White Blood Corpuscles) Platelets. Q.21 What are the functions of bone, cartilage and ligament? (3Marks) Ans. Bone-Provides support to the body and protects internal organs of body. Cartilage - Provides support and flexibility to the body parts. Tendons- It joins muscles to bone. Q.22 What is cork? Mention its uses. (3 Marks) Ans. As root and stem grow older and increase in girth, peripheral tissue of root and stem become cork. Cork cells are dead and do not have any intercellular space. Cork is protective in function. It is used in manufacture of sports goods, linoleum & for insulation. Q.23 Name the following. (2 Marks) a) Tissue that forms the inner lining of our mouth. b) Tissue that connects muscle to bone in human. c) Tissue that transports food in plants. d) Tissue that stores fat in our body. Ans. a) Squamous epithelium. b) Tendon. c) Phloem d) Adipose tissue Q.24 What is the difference between striated, unstriated and cardiac muscles? (5 Marks) Ans. The difference between striated, unstriated and cardiac muscles is as follows - Striated muscles Unstriated Cardiac muscles (Smooth) muscles 1. They are found in limbs, 1. They are present in 1. They form myocardium tongue, pharynx etc. the wall of visceral organs. of the heart. 2. Long, cylindrical 2. Short, spindle shaped 2. Short, cylindrical with with blunt ends. with pointed ends. flat ends. 3. Multinucleate, 3. Uninucleate, nucleus 3. Uninucleate, nucleus in nuclei peripheral. in the center. the center. 4. They are voluntary in 4. They are involuntary 4. They are involuntary action. in action. in action. 5. Presence of dark 5. No bands present. 5. Bands present. and light bands. Q.25 What are the functions of connective tissue? (5 Marks) Ans. The functions of connective tissue are as follows: 1. It has jelly like ground substance, which acts as lubricant. 2. Bones and cartilage form skeleton and protect the delicate organs of body. 3. Adipose tissue, another kind of connective tissue. helps in storage of fats. 4. Plasma cells make antibodies. 5. Fluid connective tissues (blood and lymph) help in the transport of materials. Q.26 Distinguish between xylem tissue and phloem tissue. (3 Marks) Ans. Xylem Phloem 1.It is a complex tissue. 1. It is a complex tissue. 2. It contains mainly dead elements like 2.It contains living cells tracheids, vessels. except phloem fibres. 3.It conducts water and minerals from roots to 3. It transports food from leaves aerial parts of the plant body. to other parts of plants.