Which equation is used to calculate the power P of the machine?

Correct Answer: C

Rationale: The correct equation for calculating power is P = ΔE / t. Power is defined as the rate at which work is done or energy is transferred. In this equation, ΔE represents the change in energy and t represents the time taken for that change. Dividing the change in energy by the time gives us the power. This equation aligns with the fundamental definition of power. Choice A (P = ΔE × t) is incorrect because it implies that power is directly proportional to both the change in energy and time, which is not always the case. Choice B (P = W × t) is incorrect because it incorrectly uses work (W) in the equation for power, while power is specifically related to the rate at which work is done, not the work itself. Choice D (P = W / ΔE) is incorrect because it suggests power is inversely proportional to the change in energy, which is not a characteristic of power.

Correct Answer: A

Rationale: The correct answer is A: nervous system. The nervous system can directly override normal endocrine controls through the release of neurotransmitters that can stimulate or inhibit hormone release from endocrine glands. The nervous system can rapidly respond to immediate changes in the internal or external environment, allowing for quick adjustments in hormone levels. Summary of why the other choices are incorrect: B: The circulatory system is not involved in directly overriding endocrine controls. C: The digestive system primarily regulates the breakdown and absorption of nutrients, not endocrine controls. D: The reproductive system is responsible for the production of sex hormones and gametes, but it does not directly override normal endocrine controls.

Correct Answer: D

Rationale: Step-by-step rationale: 1. The inferior thyroid artery typically arises from the thyrocervical trunk. 2. The thyrocervical trunk is a branch of the subclavian artery. 3. This artery supplies blood to the thyroid gland. 4. The external carotid artery and internal carotid artery do not give rise to the inferior thyroid artery. 5. The brachiocephalic trunk does not directly supply blood to the thyroid gland. In conclusion, the correct answer is D because the thyrocervical trunk is the main artery that gives rise to the inferior thyroid artery, providing blood supply to the thyroid gland.

Correct Answer: C

Rationale: The correct answer is C: Splenic artery. The splenic artery supplies the tail of the pancreas through its branches. The splenic artery runs along the superior border of the pancreas and gives off multiple branches that supply various parts of the pancreas, including the tail. A: Inferior pancreaticoduodenal artery supplies the inferior part of the pancreas. B: Left gastroepiploic artery supplies the greater curvature of the stomach. D: Superior pancreaticoduodenal artery supplies the pancreatic head and duodenum. Therefore, the splenic artery is the correct answer as it specifically supplies the tail of the pancreas.

Correct Answer: D

Rationale: The correct answer is D because insulin and glucagon are both hormones secreted by the pancreas to regulate blood glucose levels. Insulin is secreted by beta cells in response to high blood glucose levels, promoting glucose uptake by cells. Glucagon is secreted by alpha cells in response to low blood glucose levels, stimulating the release of stored glucose. Choices A and C are incorrect because insulin is secreted by beta cells, not glucagon, and they are secreted in response to high, not low, glucose levels. Choice B is incorrect because insulin lowers blood glucose levels, while glucagon raises them.