TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. Homologous structures are those that:

A. Have the same function but different origins
B. Have different functions but the same origin
C. Are similar in appearance and function due to shared ancestry
D. Are identical in both appearance and function

Correct answer: C

Rationale: Rationale: - Option A is incorrect because structures with the same function but different origins are analogous structures, not homologous structures. - Option B is incorrect because structures with different functions but the same origin are also not homologous structures; they are considered to be vestigial structures. - Option D is incorrect because structures that are identical in both appearance and function are not necessarily homologous; they could be the result of convergent evolution. Homologous structures are those that share similarities in appearance and function due to being inherited from a common ancestor. These structures may have undergone modifications over time to adapt to different functions in different species, but their fundamental similarities can be traced back to a shared evolutionary history.

2. Which of the following is a strong base commonly used in cleaning products?

A. Sodium hydroxide (NaOH)
B. Ammonium hydroxide (NHâ‚„OH)
C. Calcium hydroxide (Ca(OH)â‚‚)
D. Potassium hydroxide (KOH)

Correct answer: A

Rationale: Sodium hydroxide is a strong base commonly used in cleaning products. The other choices are also bases but are not as strong as sodium hydroxide.

3. Which of these pairs represents an example of convergent evolution?

A. Humans and chimpanzees
B. Bats and birds
C. Dolphins and sharks
D. Snakes and earthworms

Correct answer: B

Rationale: Rationale: Convergent evolution refers to the process by which different species independently evolve similar traits or characteristics due to similar environmental pressures. In the case of bats and birds, both have evolved wings for flight despite not sharing a recent common ancestor with wings. Bats are mammals, while birds are avians, yet they both have wings adapted for flight, which is a classic example of convergent evolution. A) Humans and chimpanzees share a common ancestor and have not independently evolved similar traits. C) Dolphins and sharks are not closely related, and their similarities are due to adaptations to their aquatic environment rather than convergent evolution. D) Snakes and earthworms belong to different classes (reptiles and annelids, respectively) and do not share recent common ancestors, making their similarities not a result of convergent evolution.

4. What property of a substance refers to its ability to undergo a chemical change and form new substances with different properties?

A. Density
B. Mass
C. Reactivity
D. Volume

Correct answer: c

Rationale: Reactivity refers to a substance's ability to undergo a chemical change or reaction, forming new substances with different properties.

5. Which hormone is responsible for the characteristic changes experienced during puberty, such as breast development and menstruation in females?

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

Correct answer: C

Rationale: The correct answer is C: Estrogen. Estrogen plays a crucial role in regulating the development of secondary sexual characteristics during puberty in females. It is responsible for breast development, widening of hips, and the onset of menstruation. Estrogen is mainly produced by the ovaries and is essential for the maturation of the reproductive system. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are pituitary hormones that regulate the menstrual cycle and ovulation but do not directly cause the characteristic changes seen during puberty. Progesterone is another hormone involved in the menstrual cycle and pregnancy but is not primarily responsible for the physical changes during puberty.