Describe the digestive system of a ruminant, including its parts and the role of different nutrients in animal feed.

Here are the answers to Question 1 from SECTION A.

QUESTION 1:

a)

i) One type of feed given to each animal:

• A (Cow): Grass
• B (Rabbit): Hay
• C (Chicken): Grains

ii) One nutrient from each type of feed mentioned in (i):

• From Grass (for Cow): Carbohydrates
• From Hay (for Rabbit): Fiber
• From Grains (for Chicken): Proteins

iii) One function each of the nutrient named in (ii):

• Carbohydrates: Provide energy for metabolic activities.
• Fiber: Aids in digestion and maintains gut health.
• Proteins: Essential for growth, repair of tissues, and enzyme production.

iv) The animal in Fig. 1(a) that can be classified as a ruminant is A (Cow).

b)

i) The parts labelled I, II, III, IV, and V:

• I: Larynx (Voice box)
• II: Trachea (Windpipe)
• III: Bronchus (Main airway into the lung)
• IV: Bronchioles (Smaller airways within the lungs)
• V: Alveoli (Air sacs)

ii) One function each of the parts labelled II, III, and V:

• II (Trachea): Provides a clear airway for air to enter and exit the lungs.
• III (Bronchus): Divides the air from the trachea into the left and right lungs.
• V (Alveoli): The primary site for gas exchange between the air and the blood.

iii) The most important gas during the process of respiration that is:

• ($\alpha$) used by the body: Oxygen
• ($\beta$) brought out from the body: Carbon dioxide