1. Testosterone is a crucial hormone in the male reproductive system. What is its primary function?

A. Egg production
B. Sperm production and development
C. Regulation of the menstrual cycle
D. Milk production

Correct answer: B

Rationale: The correct answer is B: Sperm production and development. Testosterone is a hormone primarily produced in the testes and is essential for the development of male reproductive tissues, including the testes and prostate. It plays a key role in the production of sperm cells (spermatogenesis) and the development of secondary sexual characteristics in males, such as facial hair and muscle mass. Testosterone is not involved in egg production (A), regulation of the menstrual cycle (C), or milk production (D) as these are functions associated with female reproductive hormones.

2. An element with atomic number 26 and mass number 56 is most likely to be:

A. Iron (Fe)
B. Cobalt (Co)
C. Nickel (Ni)
D. Manganese (Mn)

Correct answer: A

Rationale: Iron (Fe) - Fe-56 has 26 protons and aligns with the given atomic number and mass number.

3. What is the principle behind optical fibers used in communication?

A. Reflection of light within the fiber
B. Refraction of light due to different densities within the fiber
C. Total internal reflection guiding light through the fiber core
D. Diffraction of light around bends in the fiber

Correct answer: C

Rationale: Optical fibers used in communication rely on the principle of total internal reflection guiding light through the fiber core. When light enters the fiber at a certain angle, it reflects off the boundary between the core and cladding, ensuring that the light remains trapped within the core and travels along the fiber without significant loss of signal. This total internal reflection allows for efficient transmission of light signals over long distances in optical communication systems.

4. Which element shares the same group (family) on the periodic table with helium (He)?

A. Neon (Ne)
B. Boron (B)
C. Carbon (C)
D. Oxygen (O)

Correct answer: A

Rationale: Neon (Ne). Both He and Ne belong to Group 18 (Noble Gases) due to their complete and stable outer electron shells.

5. Which of the following is the main function of the kidneys?

A. To filter waste products from the blood
B. To produce urine
C. To regulate blood pressure
D. To produce hormones that help to control blood sugar levels

Correct answer: A

Rationale: Rationale: A) To filter waste products from the blood: The main function of the kidneys is to filter waste products, excess ions, and water from the bloodstream to form urine, which is then excreted from the body. This process helps maintain the body's internal environment by regulating the balance of electrolytes, fluid volume, and pH levels. B) To produce urine: While the kidneys do produce urine as a result of filtering the blood, the primary function is to filter waste products rather than solely producing urine. C) To regulate blood pressure: The kidneys do play a role in regulating blood pressure by controlling the volume of blood and the concentration of electrolytes in the body, but their main function is waste filtration. D) To produce hormones that help to control blood sugar levels: While the kidneys do produce hormones like erythropoietin and renin that play a role in various physiological processes, such as red

6. How do isotopes affect the atomic mass of an element?

A. Isotopes have no effect on the atomic mass of an element.
B. Isotopes cause the atomic mass of an element to vary slightly.
C. Isotopes cause the atomic mass of an element to be exactly the same for all isotopes of that element.
D. Isotopes cause the atomic mass of an element to vary greatly.

Correct answer: B

Rationale: The atomic mass of an element is the average mass of all the isotopes of that element. Since isotopes have different numbers of neutrons, they also have slightly different masses. This variation in mass is what causes the atomic mass of an element to be a decimal number, rather than a whole number.