State whether the following statements are true/ false .Give the explanation for each statement to support your answer. [5 MARKS]
(1) During heavy exercise the breathing rate of a person slows down.
(2) Plants carry out photosynthesis only during the day and respiration only at night.
(3) Frogs breathe through their skins as well as their lungs.
(4) The amount of air available on the mountains is more than that available on the ground.
(5) Glucose breaks down into lactic acid in the absence of oxygen.
State whether the following statements are true/ false .Give the explanation for each statement to support your answer. [5 MARKS]
(1) During heavy exercise the breathing rate of a person slows down.
(2) Plants carry out photosynthesis only during the day and respiration only at night.
(3) Frogs breathe through their skins as well as their lungs.
(4) The amount of air available on the mountains is more than that available on the ground.
(5) Glucose breaks down into lactic acid in the absence of oxygen.
Each point: 1 Mark
(1) False. During heavy exercise, more oxygen is required to meet extra demand of energy. Therefore breathing rate increases.
(2) False. Photosynthesis occurs in the presence of sunlight. Respiration is a continuous process and occurs all the time (day and night).
(3) True. Frogs breathe through skin as well as through lungs. Thus they have moist-slippery skin and lungs.
(4) False. The amount of air available at mountain is less than that available on the ground. That is why mountaineers carry oxygen with them.
(5) True. Muscle cells break down glucose into lactic acid and energy in the absence oxygen during heavy activities.
Each point: 1 Mark
(1) False. During heavy exercise, more oxygen is required to meet extra demand of energy. Therefore breathing rate increases.
(2) False. Photosynthesis occurs in the presence of sunlight. Respiration is a continuous process and occurs all the time (day and night).
(3) True. Frogs breathe through skin as well as through lungs. Thus they have moist-slippery skin and lungs.
(4) False. The amount of air available at mountain is less than that available on the ground. That is why mountaineers carry oxygen with them.
(5) True. Muscle cells break down glucose into lactic acid and energy in the absence oxygen during heavy activities.
