ATI TEAS Practice Science Test

Correct Answer: A

Rationale: The correct answer is A: Adenine. Adenine forms a complementary base pair with cytosine through hydrogen bonding in DNA. This pairing is essential for maintaining the structure and stability of the DNA double helix. Adenine and cytosine form two hydrogen bonds between them. Choices B, C, and D are incorrect because cytosine does not bind with itself (B), guanine (C), or thymine (D) in DNA. Thymine pairs with adenine, while guanine pairs with cytosine. Therefore, the correct base that binds with cytosine is adenine.

Correct Answer: A

Rationale: The hypodermis is primarily composed of adipose tissue, which is a type of connective tissue. Adipose tissue serves as a layer of insulation and energy storage in the body. It helps regulate body temperature and provides cushioning for organs. Adipose tissue is the main component of the hypodermis, making choice A the correct answer. Choices B, C, and D are incorrect because the hypodermis is not primarily composed of regular connective tissue, epithelial tissue, or muscle tissue.

Correct Answer: C

Rationale: The correct answer is C: Epithelial cells. Epithelial cells are found in the hair bulb and are responsible for hair growth because they undergo rapid cell division and differentiation to form the hair shaft. Basal cells (choice A) are a type of epithelial cell found in the skin, but they mainly function in the regeneration of the epidermis. Epidermal cells (choice B) refer to the outer layer of the skin and do not play a direct role in hair growth. Merkel cells (choice D) are specialized touch receptors found in the skin, but they are not involved in hair growth. In summary, epithelial cells in the hair bulb are specifically designed for hair growth through their rapid division and differentiation process.

Correct Answer: C

Rationale: The correct order is C: Thrombocytes, erythrocytes, and leukocytes. Thrombocytes (platelets) are the smallest, followed by erythrocytes (red blood cells), then leukocytes (white blood cells). This order is based on the size of these blood cell types, with thrombocytes being the smallest and leukocytes being the largest. Thrombocytes play a crucial role in blood clotting, erythrocytes are responsible for oxygen transport, and leukocytes are essential for immune function. Incorrect choices: A: Incorrect order; leukocytes are the largest, not the smallest. B: Incorrect order; thrombocytes are the smallest, not the largest. D: Incorrect order; leukocytes are larger than erythrocytes, so the order is incorrect.

Correct Answer: B

Rationale: To convert grams to kilograms, we divide by 1000 since there are 1000 grams in a kilogram. Therefore, 1800 grams divided by 1000 equals 1.8 kilograms. Choice B is correct. Choice A is incorrect because 0.18 is the result of dividing by 10, not 1000. Choice C is incorrect as it is 10 times the correct answer. Choice D is incorrect as it is 100 times the correct answer.