TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. Which of the following is the main function of the heart?

A. To filter blood
B. To exchange gases
C. To pump blood throughout the body
D. To produce hormones

Correct answer: C

Rationale: Rationale: The main function of the heart is to pump blood throughout the body. The heart is a muscular organ that works as a pump to circulate blood, which carries oxygen and nutrients to the body's tissues and removes waste products. Option A is incorrect because the kidneys are responsible for filtering blood. Option B is incorrect because the exchange of gases, such as oxygen and carbon dioxide, occurs in the lungs. Option D is incorrect because hormone production is primarily carried out by endocrine glands such as the pituitary gland and the thyroid gland.

2. Half-life refers to the characteristic time it takes for:

A. Radioactive intensity to completely disappear
B. The number of neutrons in a nucleus to double
C. The number of protons in a nucleus to change
D. An isotope to decay by half of its initial quantity

Correct answer: D

Rationale: The correct answer is D: An isotope to decay by half of its initial quantity. The half-life of a substance is the time it takes for half of the initial quantity of radioactive atoms to decay. This is a characteristic property of each radioactive isotope and is used to determine the rate of decay of a substance. Option A is incorrect because radioactive intensity does not completely disappear in half-life, it only decreases by half. Options B and C are unrelated to the concept of half-life and do not accurately describe its definition.

3. In meiosis, how many divisions occur, and how many daughter cells are produced?

A. One division, two daughter cells
B. Two divisions, four daughter cells
C. Four divisions, eight daughter cells
D. Eight divisions, sixteen daughter cells

Correct answer: B

Rationale: Rationale: In meiosis, there are two divisions: meiosis I and meiosis II. During meiosis I, homologous chromosomes separate, resulting in two daughter cells with half the number of chromosomes as the parent cell. In meiosis II, sister chromatids separate, resulting in a total of four daughter cells, each with a haploid set of chromosomes. Therefore, meiosis involves two divisions and produces four daughter cells.

4. Which of the following is NOT typically found in healthy urine?

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

Correct answer: B

Rationale: Glucose is NOT typically found in healthy urine because the kidneys filter glucose from the blood, and any excess is excreted in the urine. In healthy individuals, the renal threshold for glucose reabsorption is low, so glucose should not be present in significant amounts in urine. On the other hand, urea, creatinine, and electrolytes are all normal components of urine. Urea is a waste product of protein metabolism, creatinine is a waste product of muscle metabolism, and electrolytes like sodium and potassium are essential for various bodily functions and are excreted in urine. Therefore, option B is the correct answer as glucose is not typically found in healthy urine.

5. In a neutral atom, the number of electrons:

A. Must be equal to the number of protons.
B. Must be less than the number of protons.
C. Must be greater than the number of neutrons.
D. Can vary depending on the atom's temperature.

Correct answer: A

Rationale: Must be equal to the number of protons - For electrical neutrality, the positive charge of protons must be balanced by the negative charge of an equal number of electrons.