1. What is the main consequence of a malfunctioning thyroid gland that produces abnormally low levels of thyroid hormones?

A. Increased energy levels and weight loss
B. Decreased heart rate and body temperature
C. Enhanced muscle growth and bone development
D. Faster metabolism and heightened alertness

Correct answer: B

Rationale: The correct answer is B: 'Decreased heart rate and body temperature.' When the thyroid gland produces abnormally low levels of thyroid hormones (hypothyroidism), it can lead to a decrease in metabolic rate, resulting in symptoms such as fatigue, weight gain, and feeling cold. A lower metabolic rate can slow down heart rate and decrease body temperature. The other options (A, C, D) are not characteristic of hypothyroidism. Increased energy levels and weight loss, enhanced muscle growth and bone development, and faster metabolism and heightened alertness are more commonly associated with hyperthyroidism, where the thyroid gland produces excess hormones.

2. The final sentence highlights the need for

A. Public funding for scientific research and development of climate-friendly technologies.
B. Individual lifestyle changes and responsible consumption habits to reduce carbon footprints.
C. International partnerships and collaborative efforts to implement effective climate action plans.
D. Educational campaigns raising awareness about the urgency of addressing climate change.

Correct answer: C

Rationale: The emphasis on "international cooperation," "robust scientific research," and "adapting" suggests a focus on collaborative and multi-faceted solutions, aligning with C.

3. Micturition involves a combination of:

A. Gravity alone
B. Voluntary muscle contractions only
C. Involuntary muscle contractions only
D. Both voluntary and involuntary muscle contractions

Correct answer: D

Rationale: The correct answer is D: 'Both voluntary and involuntary muscle contractions.' Micturition, also known as urination, is a complex process involving both voluntary and involuntary muscle contractions. The voluntary muscle contractions allow us to control when we urinate, while the involuntary muscle contractions help to expel urine from the bladder. Gravity alone (option A) is not sufficient for micturition, as muscle contractions are necessary to empty the bladder. Similarly, relying on voluntary muscle contractions only (option B) would not be effective, as involuntary contractions are also needed to fully empty the bladder. Lastly, option C stating 'Involuntary muscle contractions only' is incorrect because voluntary muscle contractions play a crucial role in micturition. Therefore, option D is the most comprehensive and accurate choice.

4. Which digestive enzyme is primarily responsible for breaking down proteins?

A. Pepsin
B. Lipase
C. Amylase
D. Maltase

Correct answer: A

Rationale: The correct answer is A: Pepsin. Pepsin is primarily responsible for breaking down proteins in the stomach. It is an enzyme produced by the gastric chief cells in the stomach lining and works in a highly acidic environment to break down proteins into smaller peptide fragments. Lipase, on the other hand, is responsible for breaking down fats, amylase for breaking down carbohydrates, and maltase for breaking down maltose (a type of sugar). Therefore, pepsin is the correct enzyme involved in the digestion of proteins.

5. What is the difference between active and passive immunity?

A. Active immunity is short-lived, while passive immunity is long-lasting.
B. Active immunity involves the body's own immune response, while passive immunity provides immediate protection through antibodies from another source.
C. Active immunity only protects against bacterial infections, while passive immunity works against both bacteria and viruses.
D. Passive immunity requires repeated vaccinations, while active immunity is a one-time process.

Correct answer: A

Rationale: The correct answer is A: "Active immunity involves the body's own immune response, while passive immunity provides immediate protection through antibodies from another source." Active immunity is long-lasting because it involves the body's immune system producing memory cells that remember specific pathogens, providing long-term protection. Passive immunity, on the other hand, is short-lived as it involves receiving pre-formed antibodies from an external source, such as through maternal transfer or injection of antibodies, which do not create memory cells for long-lasting protection.