Q1. The answer is
• They control body activities by releasing hormones into the blood.
Endocrine glands secrete hormones directly into the bloodstream and include hypothalamus, pineal gland, pituitary gland, thyroid gland, parathyroid gland, adrenal gland, ovaries, testes, pancreas. By secreting hormones, they control body functions and activities and maintain body homeostasis. If some of the endocrine glands do not work properly, their target organ and/or function will change activity and homeostasis will be disturbed.
Q2. The answer is
• Circulatory system
The circulatory system transports oxygen and nutrients through the blood to the every single cell of the organism. Also, it picks up carbon dioxide and wastes and removes them from the organism. That way, it helps all other systems to maintain homeostasis. Without circulatory system in the organism, the cells would die because they would not get nutrients and oxygen and the waste and carbon dioxide would not be excreted from them.
Q3. The answer is • Needs less energy to maintain homeostasis.
Ectotherms (cold-blooded animals) are organisms that cannot maintain their body temperature which depends on environmental conditions. Endotherms (warm-blooded animals) are able to maintain body temperature and do not depend on changes in environmental conditions. However, to maintain homeostasis, endotherms must generate heat and this requires energy. On the other hand, ectotherms do not generate heat to maintain temperature, so they need less energy to maintain homeostasis.
Q4. The answer is • Bask in the sun on an exposed rock
As an ectotherm (a cold-blooded animal), a lizard cannot maintain its body temperature. It depends on the environmental conditions. In order to conserve its body heat in cold weather, it will bask in the sun on an exposed rock. Exposed rock is already warm and by basking there in the Sun, he will absorb warmth through its thin skin and its internal temperature will rise. Its muscles will warm up and will be prepared for hunting or running from predators.
Q5. The answer is • Regulates its body temperature partly by generating its own body heat.
Endotherms are warm-blooded animals. Their body temperature is maintained within a narrow range. To maintain their temperature, they must generate their own heat. However, this is not the only way to regulate the body temperature. They sweat or pant, so they can cool their body if necessary. Some animals can survive cold weather through torpor when their body temperature can drop temporarily.