Tissues - Exercises
Biology - Exercise
Tissue-Exercises
Q1. Define the term Tissue
Tissue is defined as a group of similar cells that work together to perform a specific function. Tissues are a cellular organisational level that falls between cells and organ systems.Q2. How many types of elements together make up the xylem tissue? Name them.
Xylem Cells are made up of three cells
- Tracheids: These are long, tapering dead cells that help conduct water. They have thick wall and dead cells at maturity.
- Xylem Vessel: These are long, tube-like dead cells that are placed one above the other. They have a thick wall and dead cells at maturity.
- Xylem Parenchyma: Parenchyma stores food. They have cytoplasm and a nucleus.
Q3. How are simple tissues different from complex tissues in plants?
Simple Tissues: These tissues perform the same function and have a similar shape. They are made Made up of a single type of cell.Complex Tissue: These tissues are made up of different types of cells. They are also known as vascular tissues as They're formed of vascular bundles.
Diffrenece between Simple and Complex Tissues |
||
|---|---|---|
| Properties | Simple Tissue | Complex Tissue |
| Cell Composition | Made of a single, homogeneous type of cell | Composed of multiple different cell types (heterogeneous) that are arranged into a single tissue |
| Function | Perform basic, uniform functions such as storage and providing support | Perform specialised functions, most notably the transport of water, minerals, and food throughout the plant |
| Origin and Structure | All cells in a simple tissue share a common origin and structure | The different cells within a complex tissue have different structures and origins |
| Examples | Parenchyma,Collenchyma & Sclerenchyma | Xylem and Phloem |
Q4. Differentiate between parenchyma, collenchyma and sclerenchyma based on their cell wall.
| Tissue | Wall Type |
|---|---|
| Parenchyma | Thin cell Wall made of cellulose |
| Collenchyma | Thin cell wall, thicker as the edges due to deposition of cellulose, pectin and hemicellulose |
| Sclerenchyma | Thick, lignified and rigid, made of lignin |
Q5. What are the functions of the stomata?
Functions of stomata:Stomata are enclosed by two kidney-shaped guard cells that facilitate gaseous exchange in the leaf.
Stomata
also facilitate transpiration, the process by which excess water is lost as water vapour through the surface of
the leaves.
Q6. Diagrammatically show the difference between the three types of muscle fibres.
Q7. What is the specific function of the cardiac muscle?
Functions of Cardiac Muscle:Muscle tissue contains contractile proteins that contract and relax to cause movement.
Muscle tissue is highly cellular and well supplied with blood vessels.
Muscle Fibres can adapt to changing demands by changing size or Fibre type composition.
Q8. Differentiate between striated, unstriated and cardiac muscles based on their structure and site/location in the body.
| Difference between striated, unstriated and cardiac muscles | |||
|---|---|---|---|
| Properties | Striated | Unstriated | Cardiac muscles |
| Structure | Cylindrical & unbranched Cell, exhibits light and dark bands called striations, multinucleated, attached to bone and form the bulk of the body's muscle mass | Long spindle-shaped and unbranched cells, uninucleated | Cylindrical, branched that form a network, exhibits striations, but lighter than striated muscles, uninucleated, connected by intercalated discs |
| Site/Location | Found in the limbs, face, tongue, and other parts of the body involved in voluntary movement. | Found in the walls of internal organs such as the stomach, intestines, uterus, and blood vessels | Exclusively found in the walls of the heart |
Q9. Draw a labelled diagram of a neuron.
Q10. Name the following.
(a) Tissue that forms the inner lining of our mouth. Squamous epithelium Tissue(b) Tissue that connects muscle to bone in humans. Tendons Tissue
(c) Tissue that transports food in plants. Phloem Tissue
(d) Tissue that stores fat in our body. Adipose Tissue
(e) Connective tissue with a fluid matrix. Blood Tissue
(f) Tissue present in the brain. Nervous Tissue
Q11. Identify the type of tissue in the following: skin, bark of a tree, bone, lining of kidney tubule, vascular bundle.
Skin Epithelial TissueBark of Tree Cork (Phellem)
Bone Connective Tissue
Lining of Kidney tubules Cuboid Epithelium
Vascular Bundle Complex permanent tissue
Q13. What is the role of epidermis in plants?
A single layer of cells forms the epidermis, and it is the outermost layer of the plant. Properties and roles of epidermis:- In epidermis tissue, the outer and sidewalls of the epidermis, cells are thicker than the inner wall.
- Epidermis cells are mostly flat cells.
- For some plants living in dry habitats, storage of water is significant and critical. So the epidermis layer is thick in those plants to avoid the loss of water.
- It protects the entire surface of the plant.
- In aerial parts of the plant, epidermal cells in its outer surface secrete a waxy, water-resistant layer. The epidermis of the desert plant has a thick layer of cutin that is called cuticle.
- In turn, this layer protects the surface of the plant against water loss, mechanical injury, and the parasitic fungi invasion.
- Epidermal cells are a continuous layer without any intercellular spaces to give protection to the plant.
Q14. How does the cork act as a protective tissue?
Cork is constituted by a layer of cells formed by the cortex, located in a strip of secondary meristem. Cork cells are dead and compactly arranged without intercellular spaces. Cork has a substance called suberin in their walls that makes it impervious to gases and water.Q.15
