1. A condition characterized by an overactive thyroid gland and excessive production of thyroid hormones is called:

A. Diabetes mellitus
B. Hyperthyroidism
C. Hypothyroidism
D. Cushing's syndrome

Correct answer: B

Rationale: The correct answer is B: Hyperthyroidism. Hyperthyroidism is a condition where the thyroid gland becomes overactive and produces an excess of thyroid hormones. This can lead to symptoms such as weight loss, rapid heart rate, and anxiety. Diabetes mellitus (A) is a condition characterized by high blood sugar levels. Hypothyroidism (C) is the opposite of hyperthyroidism, where the thyroid gland is underactive. Cushing's syndrome (D) is a disorder caused by prolonged exposure to high levels of the hormone cortisol. Therefore, in this case, the correct answer is B as it specifically relates to an overactive thyroid gland.

2. The protective fluid surrounding the brain and spinal cord is called:

A. Blood
B. Cerebrospinal fluid
C. Plasma
D. Myelin

Correct answer: B

Rationale: The correct answer is B: Cerebrospinal fluid. Cerebrospinal fluid is a clear, colorless liquid that surrounds the brain and spinal cord, providing cushioning and protection against physical impact. It also helps to maintain a stable environment for the central nervous system by regulating pressure and removing waste products. Blood (option A) is not the fluid that directly surrounds the brain and spinal cord. Plasma (option C) is the liquid component of blood and is not specific to the central nervous system. Myelin (option D) is a fatty substance that forms a protective sheath around nerve fibers but is not the fluid surrounding the brain and spinal cord.

3. He asserts the importance of promoting a positive organizational culture in their unit. Which

A. Proactive and caring with one another
B. Competitive and perfectionist
C. Powerful and oppositional
D. Obedient and uncomplaining

Correct answer: A

Rationale: The correct answer is A: 'Proactive and caring with one another.' When promoting a positive organizational culture, it is essential to foster a supportive environment where individuals are proactive in their approach and demonstrate care towards one another. This type of culture encourages collaboration, open communication, and empathy among team members, leading to higher levels of job satisfaction and overall performance. Being competitive and perfectionist (option B) can create a stressful and unhealthy work environment, while being powerful and oppositional (option C) or obedient and uncomplaining (option D) can stifle creativity and innovation. Therefore, the most suitable traits for promoting a positive organizational culture are being proactive and caring with one another.

4. Which of the following properties is NOT characteristic of a covalent bond?

A. Sharing of electrons between atoms
B. High melting and boiling points
C. Low electrical conductivity in solid state
D. Directional bonding

Correct answer: B

Rationale: Covalent bonds are formed by the sharing of electrons between atoms. This sharing results in the formation of molecules with directional bonding, where the atoms are held together in a specific orientation. Covalent compounds generally have low melting and boiling points compared to ionic compounds, as the intermolecular forces in covalent compounds are weaker. Additionally, covalent compounds do not conduct electricity in the solid state because the electrons are localized between the atoms and not free to move and carry charge.

5. The fluid-filled sacs that cushion the brain within the skull are called:

A. Meninges
B. Cerebrospinal fluid
C. Dura mater
D. Arachnoid mater

Correct answer: B

Rationale: The correct answer is B: Cerebrospinal fluid. Cerebrospinal fluid is a clear, colorless fluid that surrounds the brain and spinal cord, acting as a cushion to protect the central nervous system from injury. Meninges (Option A) are the protective membranes that cover the brain and spinal cord, while the dura mater (Option C) and arachnoid mater (Option D) are specific layers of the meninges. However, cerebrospinal fluid is the fluid-filled sac that directly cushions the brain within the skull, making it the most appropriate answer for this question.