1. A study finds a link between increased sugar intake and obesity. Does this confirm sugar causes obesity?

A. Yes, the study definitively proves causation.
B. No, correlation does not equal causation, other factors might be involved.
C. We need more research to isolate the specific role of sugar.
D. This only applies to people with genetic predispositions to obesity.

Correct answer: C

Rationale: Correlation suggests a link, but other factors might contribute. Further research is needed to establish the direction and strength of any causal relationship.

2. Why are isotopes of the same element chemically similar?

A. They have the same number of protons.
B. They have the same number of electrons.
C. Their chemical properties are identical.
D. They share the same electron configuration.

Correct answer: A

Rationale: They have the same number of protons. This determines the element's identity and its interactions with other elements, leading to similar chemical behavior, even if the number of neutrons differs.

3. Dense irregular connective tissue, found in tendons and ligaments, provides:

A. Flexibility
B. Lubrication
C. Insulation
D. Tensile strength

Correct answer: D

Rationale: The correct answer is D: 'Tensile strength.' Dense irregular connective tissue is composed of tightly packed collagen fibers arranged in a random pattern, providing resistance to tension forces. This structural arrangement is ideal for tendons and ligaments, as they need to withstand pulling and stretching forces. 'Flexibility' (A) is more characteristic of elastic fibers, 'Lubrication' (B) is provided by synovial fluid in joints, and 'Insulation' (C) is typically associated with adipose tissue. Therefore, tensile strength is the primary function of dense irregular connective tissue in tendons and ligaments.

4. What is the function of arrector pili muscles?

A. To control sweat production
B. To contract and cause goosebumps
C. To produce sebum
D. To sense touch

Correct answer: B

Rationale: The correct answer is B: 'To contract and cause goosebumps.' Arrector pili muscles are small muscles attached to hair follicles in the skin. When these muscles contract, they cause the hair to stand upright, resulting in the appearance of goosebumps. This physiological response is a remnant of our evolutionary past when our ancestors had more hair, and the raised hair helped to trap air for insulation or to make them look larger when threatened. Therefore, the function of arrector pili muscles is not to control sweat production (A), produce sebum (C), or sense touch (D), but rather to create the physical response of goosebumps.

5. What is the term for a group of organisms that can interbreed and produce fertile offspring?

A. Genus
B. Phylum
C. Kingdom
D. Species

Correct answer: D

Rationale: Rationale: A species is defined as a group of organisms that can interbreed and produce fertile offspring. This ability to interbreed and produce fertile offspring is a key characteristic that distinguishes one species from another. In contrast, a genus (option A) is a taxonomic rank that includes one or more species that are closely related, while a phylum (option B) and a kingdom (option C) are higher taxonomic ranks that encompass multiple species.

6. What is the main component of sweat?

A. Urea
B. Glucose
C. Water
D. Electrolytes

Correct answer: C

Rationale: Rationale: - Sweat is primarily composed of water, making up the majority of its content. Water helps regulate body temperature by evaporating from the skin's surface, which cools the body down. - While sweat does contain small amounts of other substances like urea, glucose, and electrolytes, water is the main component that is secreted by sweat glands to help regulate body temperature during physical activity or in response to heat.