Test: Tissue- 1 - Class 9 MCQ

• Meristematic tissue is characterized by cells that are very active, with dense cytoplasm, thin cellulose walls, and prominent nuclei.
• These cells lack vacuoles because they are involved in rapid cell division and do not require storage.
• Meristematic tissue is indeed classified into apical, lateral, and intercalary based on their location.
• However, it is not directly responsible for the permanent shape, size, and function of cells; that role is taken up by permanent tissue formed after differentiation.
• Therefore, statements (i), (ii), and (iii) are correct.

Sclerenchyma is the tissue in plants that provides rigidity and strength, making the plant hard and stiff due to its thickened cell walls.

Simple squamous epithelial cells are extremely thin and flat and form a delicate lining. The oesophagus and the lining of the mouth, alveoli of the lungs, etc are lined with squamous epithelium. They help in protection, excretion, gas exchange, etc.

Sclerenchyma cells have thickened lignified walls, which make them strong and waterproof. They are commonly classified into support types and conducting forms. Support sclerenchyma is comprised of sclereids and fibers.

Sclerenchyma (i) transverse section, (ii) longitudinal section.

• Option A: Parenchyma - Living cells with thick walls 
  This is incorrect. Parenchyma consists of relatively unspecialised living cells with thin cell walls, not thick walls. They are usually loosely arranged with large intercellular spaces.
• Option B: Collenchyma
  Cells with lignified thick walls - This is incorrect. Collenchyma cells are living, elongated, and have irregularly thickened cell walls, but they are not lignified. Lignin is a characteristic of sclerenchyma cells.
• Option C: Sclerenchyma - Dead cells with thick walls
  This is correct. Sclerenchyma cells are dead and have thickened cell walls due to lignin. These thick walls provide mechanical support and strength to the plant parts.
• Option D: Parenchyma - Cells with no intercellular spaces
  This is incorrect. Parenchyma cells are usually loosely arranged with large intercellular spaces, allowing for storage and the movement of substances.

The walls of cork cells are heavily thickened with an organic substance, suberin. Suberin makes these cells impervious to water and gases.

The inner lining of the intestine is primarily composed of columnar epithelium, which facilitates absorption and secretion. This type of epithelium is characterized by tall cells, aiding in movement across the epithelial barrier.

• Tendons connect muscles to bones. Tendons (another type of tough connective tissue) on each side of a joint attach to muscles that control the movement of the joint.
• Ligaments connect bones together.

• Assertion Correctness: The assertion is true. Muscular tissue indeed consists of elongated cells responsible for movement in our body.
• Reason Correctness: The reason is also correct. Muscles do contain special proteins called contractile proteins which contract and relax to cause movement.
• Explanation: The reason provided logically explains why muscular tissue is responsible for movement. The contractile proteins within muscles enable them to contract and relax, leading to movement. Thus, the reason is the correct explanation of the assertion.

Ciliated columnar epithelium moves mucus and other substances via cilia and is found in the upper respiratory tract, the fallopian tubes, the uterus, and the central part of the spinal cord.

• Collenchyma:

  • Retains protoplasm at maturity.
  • Has non-uniformly thickened walls, often at the corners.
  • Provides flexibility and tensile strength to growing plant parts.

• Sclerenchyma:

  • Consists of dead cells at maturity, as the protoplasm is lost.
  • Has uniformly thickened walls, typically lignified.
  • Provides rigidity and strength to mature plant parts.

• The primary differences are:

Collenchyma retains protoplasm at maturity, whereas sclerenchyma does not.

Collenchyma has non-uniformly thickened walls, while sclerenchyma has uniformly thickened lignified walls.

Limbs are the voluntary muscles because we can completely control them.

• The assertion that meristematic tissues in plants are primarily responsible for plant growth is correct. These tissues contain actively dividing cells, which contribute to the increase in length and girth of plant organs, supporting the assertion.
• The reason statement is also true. Meristematic tissues indeed have cells that divide rapidly, leading to growth. This aligns with the characteristic function of meristems in plants.
• Furthermore, the reason provides an accurate and logical explanation for the assertion. The actively dividing cells in meristems are responsible for the growth of plant organs, thus justifying why Reason is the correct explanation of Assertion.

Specialized parenchyma cells known as chlorenchyma found in plant leaves contain chloroplasts. This allows them to perform a photosynthetic function and responsible for the storage of starch. 

So, the correct answer is 'Chlorenchyma and parenchyma.'

• The Assertion (A) is true as parenchyma tissue indeed generally stores food in plants.

• The Reason (R) is also true as collenchyma tissue provides flexibility to various parts of a plant.

• However, the Reason is not the correct explanation of the Assertion. While both statements are correct, they are independent of each other and do not directly explain or support each other.

• Sclerenchyma cells are the permanent tissues present in the plants.
• They provide hardness and stiffness to the plant and are composed of dead cells.
• This tissue is present in stems around vascular bundles in the veins of leaves and in hard covering of seeds and nuts.

A tendon is a flexible but inelastic cord of strong fibrous collagen tissue attaching a muscle to a bone.

• Option A: Apical meristem - Increases girth of stem This is incorrect. Apical meristem is located at the growing tips of stems and roots and is responsible for the increase in length, not girth.
• Option B: Lateral meristem - Increases length of stem This is incorrect. Lateral meristem, such as the cambium, is responsible for the increase in the girth (thickness) of the stem, not the length.
• Option C: Intercalary meristem - Located at the growing tips of stems This is incorrect. Intercalary meristem is located near the nodes of the plant and helps in the growth of the internodes (the stem segments between nodes), not at the growing tips.
• Option D: Apical meristem - Located at the growing tips of stems This is correct. Apical meristem is found at the tips of stems and roots and is responsible for the vertical growth of the plant.
• Therefore, the correctly matched pair is Option D: Apical meristem - Located at the growing tips of stems.