1. Which hormone primarily triggers ovulation in the female menstrual cycle?

A. Estrogen
B. Progesterone
C. Luteinizing hormone (LH)
D. Follicle-stimulating hormone (FSH)

Correct answer: C

Rationale: The correct answer is C: Luteinizing hormone (LH). LH is the hormone responsible for triggering ovulation in the female menstrual cycle. During the menstrual cycle, LH surge occurs around day 14, which stimulates the release of a mature egg from the ovary. This surge in LH is crucial for the rupture of the mature follicle and the release of the egg, marking the onset of ovulation. Estrogen and progesterone play important roles in regulating the menstrual cycle, but LH specifically triggers ovulation by signaling the release of the egg from the ovary.

2. Cartilage, found in joints and the ear, is a type of:

A. Epithelial tissue
B. Connective tissue
C. Muscle tissue
D. Nervous tissue

Correct answer: B

Rationale: The correct answer is B: Connective tissue. Cartilage is a tough, flexible type of connective tissue that provides support and cushioning in joints and the ear. It is made up of specialized cells called chondrocytes embedded in a gel-like matrix of collagen and proteoglycans. Epithelial tissue (A) covers and lines body surfaces, muscle tissue (C) is responsible for movement, and nervous tissue (D) transmits signals in the body. In contrast, cartilage primarily serves a structural and protective function, placing it within the category of connective tissue.

3. What is the relationship between genetic drift and the founder effect?

A. Founder effect is a cause of genetic drift within a small population
B. Genetic drift is a cause of the founder effect in new populations
C. They are the same phenomenon with different names
D. They are unrelated concepts.

Correct answer: A

Rationale: Rationale: - The founder effect is a specific type of genetic drift that occurs when a small group of individuals establishes a new population, leading to a loss of genetic variation. - Genetic drift, on the other hand, is a broader concept that refers to random changes in allele frequencies in a population over time due to chance events. - Therefore, the founder effect is a specific scenario within the broader concept of genetic drift, where the establishment of a new population by a small number of individuals leads to genetic changes in the population.

4. Which of the following is an example of a nonpolar solvent?

A. Water
B. Ethanol
C. Acetone
D. Hydrochloric acid

Correct answer: B

Rationale: Rationale: - Water (option A) is a polar solvent due to its uneven distribution of charge, with the oxygen atom being partially negative and the hydrogen atoms being partially positive. - Ethanol (option B) is a nonpolar solvent because it has a symmetrical molecular structure that does not result in significant charge separation. - Acetone (option C) is a polar solvent as it contains a carbonyl group that results in a partial negative charge on the oxygen atom. - Hydrochloric acid (option D) is a polar solvent due to the presence of the highly electronegative chlorine atom, which results in a partial negative charge.

5. 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.

6. The WBC (white blood cell) type responsible for the initial attack on pathogens is:

A. Red blood cells
B. Platelets
C. Phagocytes
D. Lymphocytes

Correct answer: C

Rationale: The correct answer is C: Phagocytes. Phagocytes are a type of white blood cell that plays a crucial role in the immune response by engulfing and destroying pathogens. They are the first line of defense against invading microorganisms, initiating the initial attack on pathogens. Red blood cells (option A) are responsible for carrying oxygen, not for immune responses. Platelets (option B) are involved in blood clotting. Lymphocytes (option D) are another type of white blood cell but are mainly responsible for specific immune responses rather than the initial attack on pathogens.