10 questions · Form 1 Science Bab 3: Coordination and Response
Which animal behavior aids cooling through saliva evaporation on its tongue?
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. Which animal behavior aids cooling through saliva evaporation on its tongue?
Answer: B
Panting allows dogs to evaporate saliva off their tongue and respiratory tract, lowering their core body temperature.
2. Why do guard cells close stomata during periods of extreme heat or drought?
Answer: B
Closing stomata prevents water vapor from escaping, protecting the plant from severe dehydration.
3. Which cell structure directly controls the opening and closing of a stomatal pore in plant leaves?
Answer: B
A pair of specialized guard cells flanking each stomatal pore alter their turgor pressure to open or close it.
4. Which organ in the human excretory system regulates both water and mineral salt levels in the blood?
Answer: B
Kidneys filter blood and adjust the reabsorption of water and salts to maintain osmotic balance.
5. What is the primary role of hair standing upright when erector muscles contract in cold weather?
Answer: B
Upright hair traps a boundary layer of warm air next to the skin, serving as an insulating barrier against heat loss.
6. Why is homeostasis vital for cellular enzyme function in the human body?
Answer: A
Enzymes are sensitive biological catalysts; extreme changes in temperature or pH reduce their activity or cause denaturation.
7. Which hormone is released by the brain to increase water reabsorption in the kidneys during dehydration?
Answer: B
Anti-diuretic hormone (ADH) signals the kidneys to reabsorb more water back into the bloodstream.
8. What change in metabolic rate occurs when human body temperature drops below normal?
Answer: B
Increased metabolic activity breaks down nutrients faster, generating thermal energy to raise body temperature.
9. How do kidneys respond when body water levels are excessively high?
Answer: B
When surplus water is present, less water is reabsorbed by the kidneys, resulting in a large volume of light, dilute urine.
10. How does a cold-blooded animal like a reptile regulate its body temperature?
Answer: B
Ectotherms (cold-blooded animals) rely on external heat sources, moving between sunny spots and shade to manage body temperature.