What is Digesstive system? List 4 modification/mechanisms of feeding.

Part A

1. Digestion is the breaking down of large food substances into simple and absorbable forms.

   • The correct option is (d) Digestion.

2. Mosquitoes engage sucking mechanisms for feeding.

   • The correct option is (a) Sucking.

3. Goats engage grinding mechanisms for feeding.

   • The correct option is (d) Grinding.

4. Movement of metabolic materials from one part of the organism to another is facilitated by a transport system.

   • The correct option is (a) transport system.

5. Transport of manufactured food substances from leaves to all parts of the plant is called translocation.

   • The correct option is (d) Translocation.

6. A situation where the population of a given habitat increases beyond the resources the habitat can sustain means overpopulation.

   • The correct option is (b) overpopulation.

7. Auxin promotes cell elongation and brings about growth in the stem.

   • The correct option is (d) Auxin.

8. The ability of all living things to respond to internal and external stimuli is called irritability.

   • The correct option is (a) irritability.

9. A climax community means a stable and unchanging community.

   • The correct option is (a) climax.

10. The process of filtering materials from the glomerulus into the Bowman's capsule is called ultrafiltration.

    • The correct option is (b) ultrafiltration.

Part B

1. In a tabular form, differentiate between bone and cartilage.

| Feature | Bone | Cartilage | | :---------------- | :--------------------------------------- | :----------------------------------------- | | Matrix | Hard, rigid, calcified | Flexible, elastic, non-calcified | | Blood Supply | Rich blood supply (vascular) | Poor or no blood supply (avascular) | | Cells | Osteocytes | Chondrocytes | | Flexibility | Inflexible | Flexible | | Function | Structural support, protection, mineral storage | Flexible support, reduces friction, shock absorption |

a. List 4 functions of cartilage.

• Provides flexible support (e.g., in the nose, ear, trachea).
• Reduces friction between bones at joints (articular cartilage).
• Acts as a shock absorber, cushioning joints.
• Forms the embryonic skeleton, which is later replaced by bone.

2. In a tabular form differentiate between Mitosis and Meiosis.

| Feature | Mitosis | Meiosis | | :------------------ | :--------------------------------------- | :----------------------------------------- | | Cell Type | Somatic cells | Germ cells (for reproduction) | | Number of Divisions | One | Two | | Daughter Cells | Two diploid (2n) daughter cells | Four haploid (n) daughter cells | | Genetic Identity | Genetically identical to parent cell | Genetically different from parent cell | | Purpose | Growth, repair, asexual reproduction | Sexual reproduction, genetic variation |

a. Mention 4 factors affecting growth.

• Genetic factors: Inherited traits determine potential growth.
• Nutritional factors: Availability of essential nutrients for cell division and development.
• Hormonal factors: Presence and balance of growth-regulating hormones.
• Environmental factors: Conditions like temperature, light, water availability, and space.

3. What is transport system?

A transport system is a network of specialized tissues or organs that moves essential substances, such as nutrients, water, gases, hormones, and waste products, throughout an organism to ensure all cells and tissues receive what they need and remove what they don't.

a. List 5 materials needed for transport in plants.

• Water
• Mineral salts (ions)
• Manufactured food (sugars/sucrose)
• Plant hormones (e.g., auxins, gibberellins)
• Gases (oxygen and carbon dioxide, though primarily by diffusion)