TEAS 7 science practice questions

Correct Answer: A

Rationale: A molecular clock is a method used to estimate the time of divergence between species by measuring the accumulation of mutations in DNA sequences. This method relies on the assumption that mutations occur at a relatively constant rate over time. If the rate of mutation were not constant, it would be challenging to accurately estimate the evolutionary divergence time between species. Therefore, option A is the most appropriate choice as it aligns with the fundamental principle underlying the molecular clock hypothesis. Option B is incorrect because the assumption that species with more morphological similarities diverged more recently does not directly relate to the concept of molecular clocks and the accumulation of mutations in DNA sequences. Option C is incorrect because mutations are not always beneficial and do not always contribute to increased fitness. Mutations can be neutral or deleterious as well, and their accumulation is what is used to estimate evolutionary di

Correct Answer: C

Rationale: The correct term for the process of bone formation and breakdown is remodeling. Ossification specifically refers to bone formation, while resorption pertains to bone breakdown. Remodeling encompasses both processes, as it involves the continuous cycle of bone formation and resorption to maintain bone strength and structure. Choice A, 'Ossification,' is incorrect as it only refers to bone formation. Choice B, 'Resorption,' is incorrect as it only refers to bone breakdown. Choice D, 'All of the above,' is incorrect as it includes terms that are not comprehensive of both bone formation and breakdown.

Correct Answer: D

Rationale: The correct answer is D, Sodium bicarbonate. Sodium bicarbonate, commonly known as baking soda, is a compound that plays a crucial role in maintaining pH balance in the body. When ingested, sodium bicarbonate acts as a buffer, helping to regulate the body's pH levels. It is essential for various physiological functions. Choices A, B, and C are incorrect. Potassium, calcium, and sodium are important minerals in the body but are not components of baking soda or directly responsible for maintaining pH balance in the same way as sodium bicarbonate.

Correct Answer: C

Rationale: The correct answer is the prostate gland (Choice C). The prostate gland, located near the bladder, is responsible for producing seminal fluid. This fluid, along with sperm from the testes, makes up semen. The bladder stores urine, the urethra is a tube that carries urine from the bladder out of the body, and the kidney filters waste from the blood to produce urine. The prostate gland's specific function is to secrete a milky, alkaline fluid that mixes with sperm during ejaculation to form semen. This fluid helps nourish and protect the sperm, aiding in their motility and viability. Therefore, the prostate gland plays a crucial role in male reproductive function by contributing to the composition and quality of semen, essential for fertility.

Correct Answer: B

Rationale: A spasm is a repetitive, involuntary muscle contraction that can cause pain and stiffness. While cramps are a type of spasm, not all spasms are cramps. Tics are sudden, repetitive movements or sounds made involuntarily. Fibrosis refers to the formation of excess fibrous connective tissue in an organ or tissue as part of a reparative or reactive process. In this context, a spasm best fits the description provided, making it the correct answer. Cramp, although related to spasms, is more specific and not the general term being sought. Tic does not describe a muscle contraction but rather sudden movements or sounds. Fibrosis does not directly relate to muscle contractions but rather to the formation of excess fibrous tissue in organs or tissues.