Which division of the nervous system is responsible for the 'fight or flight' response, preparing the body to respond to stressful situations?
- A. Somatic nervous system
- B. Autonomic nervous system
- C. Peripheral nervous system
- D. Central nervous system
Correct Answer: B
Rationale: The autonomic nervous system is correctly identified as the division responsible for the 'fight or flight' response, which readies the body to react to stressful situations. This system regulates involuntary bodily functions, such as heart rate, pupil dilation, and adrenaline release during stress. The somatic nervous system controls voluntary movements and skeletal muscle activity, not the automatic responses seen in the 'fight or flight' reaction. The peripheral nervous system connects the central nervous system to the body's organs and limbs, facilitating communication, while the central nervous system, comprising the brain and spinal cord, serves as the primary control center of the body, integrating and processing information.
You may also like to solve these questions
According to the Cahn-Ingold-Prelog (CIP) ranking system, which functional group has the highest priority?
- A. Alcohol (OH)
- B. Aldehyde (CHO)
- C. Carboxylic Acid (COOH)
- D. Amine (NH2)
Correct Answer: C
Rationale: In the Cahn-Ingold-Prelog (CIP) ranking system, functional groups are prioritized based on the atomic number of the atoms directly attached to the functional group. Carboxylic acid (COOH) holds the highest priority as the carbon atom is directly bonded to two oxygen atoms, which have higher atomic numbers compared to carbon, hydrogen, or nitrogen. The higher the atomic number of the attached atoms, the higher the priority of the functional group in the CIP ranking system. Therefore, choices A, B, and D are incorrect as they have lower atomic numbers in the atoms directly attached to them, making them lower in priority according to the CIP system.
Dietary fiber, although not fully digested by the body, plays a crucial role in digestion. What is one of the main benefits of consuming sufficient dietary fiber?
- A. Provides a concentrated source of energy
- B. Aids in the absorption of vitamins and minerals
- C. Promotes satiety and gut health
- D. Breaks down complex carbohydrates
Correct Answer: C
Rationale: Consuming sufficient dietary fiber promotes satiety and gut health by adding bulk to the diet, helping with feelings of fullness, and supporting healthy digestion. Additionally, fiber aids in regulating bowel movements and maintaining a healthy gut microbiota, contributing to overall digestive wellness. It does not provide a concentrated source of energy as fiber is not fully digested for energy production, nor does it directly aid in the absorption of vitamins and minerals. Fiber does not break down complex carbohydrates but rather assists in their digestion and absorption by slowing down the process, which helps in maintaining stable blood sugar levels and promoting better overall health.
What is the main function of vacuoles in plant cells?
- A. To provide structural support for the cell
- B. To transport substances in and out of the cell
- C. To synthesize proteins and lipids
- D. To store water, enzymes, and waste products
Correct Answer: D
Rationale: Vacuoles in plant cells primarily function as storage organelles. They store water, enzymes, pigments, and waste products, helping to maintain turgor pressure within the cell. This turgor pressure provides structural support for the plant cell. While vacuoles can also participate in transporting substances within the cell, their main role is storage. The synthesis of proteins and lipids is mainly handled by other organelles such as the endoplasmic reticulum and Golgi apparatus. Choice A is incorrect because while vacuoles indirectly contribute to structural support by maintaining turgor pressure, their primary function is storage. Choice B is incorrect as vacuoles are not primarily responsible for transporting substances in and out of the cell. Choice C is incorrect as vacuoles do not synthesize proteins and lipids; this function is carried out by other organelles.
Which hormone, produced by the adrenal glands, is essential for regulating electrolyte balance, particularly sodium and potassium, in the body?
- A. Aldosterone
- B. Epinephrine
- C. Cortisol
- D. Insulin
Correct Answer: A
Rationale: Aldosterone is a hormone produced by the adrenal glands that plays a crucial role in maintaining electrolyte balance, specifically by regulating sodium and potassium levels in the body. Its primary function involves acting on the kidneys to increase the reabsorption of sodium and water while promoting the excretion of potassium. This process is essential for regulating blood pressure, fluid balance, and electrolyte concentrations in the body. Epinephrine is associated with the fight or flight response, cortisol is a stress hormone, and insulin is responsible for regulating blood sugar levels as produced by the pancreas. Therefore, the correct answer is Aldosterone as it directly targets electrolyte balance, particularly sodium and potassium, in the body.
Which hormone, produced by the thyroid gland, regulates calcium levels in the blood by enhancing calcium absorption in the intestines and reducing calcium loss in the kidneys?
- A. Calcitonin
- B. Parathyroid hormone (PTH)
- C. Thyroxine
- D. Insulin
Correct Answer: A
Rationale: Calcitonin is the hormone produced by the thyroid gland that regulates calcium levels in the blood. It enhances calcium absorption in the intestines and reduces calcium loss in the kidneys. Parathyroid hormone (PTH) operates oppositely to calcitonin by increasing calcium levels in the blood. Thyroxine is a thyroid gland hormone that primarily regulates metabolism, not calcium levels. Insulin, produced by the pancreas, is responsible for controlling blood sugar levels, not calcium levels. Therefore, the correct answer is Calcitonin as it specifically targets calcium regulation in the body.