Correct Answer: A. contains the genetic material

Correct Answer: C. Trypsin

Correct Answer: B. brick-red

Correct Answer: C. Ethylene

Correct Answer: B. sudan savanna

Explanation

(a)(1) Voluntary action - involves the response to a stimulus that is controlled at will by the brain. in this action, an impulse is carried from a sensory neurone via the spinal cord to the brain which interprets and sends the message back through the motor neurone to effector organ. The action is not automatic. e.g. running, writing, jumping, laughing, reading, smiling.

(II) Involuntary action or reflex action-It is a rapid or automatic response to a stimulus. It does not involve the brain for initiation. Therefore, the action is not under the control of the will, e.g. sneezing, coughing, knee jerk, salivation, secretion of grand, blinking

(b)(i) Functions of insulin: (1) Assists in oxidation of glucose to produce energy (2) regulates the amount or level of glucose in the blood (3) assists in protein synthesis in some cells

(ii) Functions of auxin.

(1) Promotes lateral bud development.

(2) promotes reproduction, flowering and fruit formation in plants.

(3) promotes the production of adventitious roots

(c) Experiment to show that plant roots respond positively to gravity:

Aim - To demonstrate that plant roots respond positively to gravity. Apparatus: A bean seedling, Wet blotting paper, damp saw dust, cupboard.

Procedure: Put some dust on a wet blotting paper and place the bean seedling on the saw dust horizontally. Carry the set up and place it inside a dark cupboard to eliminate light for few days.

Observation: When observed after few days, one will discover that the root has curved and growing downwards while the shoot grow upward. Conclusion: Since the root has grown downwards and the shoot upwards, we can say that roots respond to gravity, showing positive geotropism while the shoot shows negative geotropism.

Correct Answer: A. hydrotropism

Correct Answer: B. lichens

Correct Answer: B. providing resistance against malaria

Correct Answer: C) Fishes

Explanation

This question is asking which organism has a closed and single circulatory system. The options given are Insect, Earthworm, Fishes and Mammals. A circulatory system is the system in our bodies that carries blood and oxygen to all the organs and tissues in our body. There are two types of circulatory systems, open and closed. An open circulatory system is when blood is not contained in vessels and flows freely through the body cavity, while a closed circulatory system is when blood is contained in vessels and pumped by the heart. In this question, the organism that exhibits a closed and single circulatory system is Fishes. Fish have a heart that pumps blood throughout their body in a closed system of blood vessels. This is different from an open circulatory system, which is found in insects and earthworms. In an open circulatory system, blood is pumped by the heart into a body cavity where it bathes the organs and tissues. It's important to note that mammals also have a closed circulatory system, but they have a double circulatory system, which means the blood flows through two separate circuits. This is different from Fishes, which have a single circulatory system. In summary, the organism that exhibits a closed and single circulatory system is Fishes. Insects and earthworms have an open circulatory system, while mammals have a closed double circulatory system.