1. Which hormone is responsible for regulating sleep-wake cycles and is influenced by light exposure?

A. Melatonin
B. Cortisol
C. Estrogen
D. Glucagon

Correct answer: A

Rationale: The correct answer is A: Melatonin. Melatonin is a hormone produced by the pineal gland in the brain and plays a crucial role in regulating the sleep-wake cycle, also known as the circadian rhythm. Melatonin levels typically rise in the evening in response to darkness and help signal to the body that it's time to sleep. Exposure to light, especially blue light, can inhibit the production of melatonin, making us more alert and awake. Cortisol (option B) is a stress hormone that helps regulate metabolism and immune response. Estrogen (option C) is a female sex hormone, and glucagon (option D) is a hormone that increases blood sugar levels. Therefore, the hormone responsible for regulating sleep-wake cycles and influenced by light exposure is melatonin.

2. What happens to the speed of a sound wave when it travels from air to water?

A. It increases because water is denser.
B. It decreases because water is denser.
C. It remains the same.
D. Speed depends on the frequency, not the medium.

Correct answer: A

Rationale: Sound waves travel faster in denser mediums like water compared to air due to stronger interactions between particles.

3. Which hormone is crucial for stimulating sperm production in males?

A. Estrogen
B. Progesterone
C. Testosterone
D. Insulin

Correct answer: C

Rationale: The correct answer is C: Testosterone. Testosterone is the primary male sex hormone and is crucial for stimulating sperm production in males through the process of spermatogenesis. It is produced in the testes and plays a key role in the development and maintenance of male reproductive tissues, including the testes and prostate. Estrogen and progesterone are primarily female sex hormones, while insulin regulates blood sugar levels and metabolism. Therefore, testosterone is the hormone specifically responsible for stimulating sperm production in males.

4. Scoliosis is a condition characterized by abnormal lateral curvature of the spine. Which part of the spine is most commonly affected?

A. Cervical spine (neck)
B. Thoracic spine (upper back)
C. Lumbar spine (lower back)
D. All of the above

Correct answer: B

Rationale: The correct answer is B: Thoracic spine (upper back). Scoliosis typically affects the thoracic spine more commonly than the cervical or lumbar spine. The thoracic spine, which is the upper back region, is the most common area for the abnormal lateral curvature of the spine to occur in cases of scoliosis. This is due to the natural curvature and structure of the spine in this region. While scoliosis can affect other parts of the spine as well, the thoracic spine is most frequently impacted, making it the correct answer in this case.

5. Ms. Valencia is responsible to the number of personnel reporting to her. This principle refers

A. Span of control
B. Unity of command
C. Carrot and stick principle
D. Esprit dâ€™ corp

Correct answer: B

Rationale: The correct answer is B: Unity of command. Unity of command is a fundamental principle of management stating that each employee should receive orders from only one supervisor to avoid confusion and ensure clarity in the chain of command. In this scenario, Ms. Valencia's responsibility for the number of personnel reporting to her aligns with the concept of unity of command. Span of control refers to the number of subordinates a supervisor can efficiently manage, while the carrot and stick principle involves motivating employees through rewards and punishments. Esprit dâ€™ corp refers to the sense of unity and camaraderie within a group.

6. The stratified squamous epithelium found in the skin is adapted for:

A. Absorption
B. Secretion
C. Protection
D. Gas exchange

Correct answer: C

Rationale: The correct answer is C: Protection. Stratified squamous epithelium is a type of tissue that is well-suited for protection as it consists of multiple layers of cells that provide a barrier against physical and chemical damage. In the skin, this epithelium helps protect the body against external threats such as pathogens, UV radiation, and mechanical abrasion. Absorption (A) and secretion (B) are typically functions of other types of epithelial tissues, such as simple columnar or simple cuboidal epithelium. Gas exchange (D) is primarily facilitated by tissues like the alveolar epithelium in the lungs, not stratified squamous epithelium in the skin.