Practice Science TEAS Test

Correct Answer: C

Rationale: The correct answer is C: Sciatic nerve. The sciatic nerve is the longest and thickest nerve in the human body, running from the lower back down the back of each leg. Its length allows it to innervate a large portion of the lower body. The other choices, A: Dorsal root ganglion and B: Laryngeal nerve, are not nerves but rather specific structures within the nervous system. Choice D: None of the above is incorrect as the sciatic nerve is indeed the nerve with the longest axon in the human body.

Correct Answer: D

Rationale: The independent variable is the factor that the researcher manipulates or controls. In this experiment, the independent variable is the dog food type as it is being purposely changed to observe its effect on the dependent variable. Time is not manipulated, dog weight and species are not changed intentionally, making them unsuitable as independent variables. The correct answer is D because it is the variable that is being tested and controlled in the experiment.

Correct Answer: A

Rationale: The correct answer is A. Macrophages are not found abundantly in the blood as they primarily reside in tissues. Neutrophils are the most abundant white blood cells in the blood. Choice B is correct as macrophages are indeed larger than neutrophils. Choice C is correct as macrophages are long-lived cells. Choice D is correct as monocytes are produced in the bone marrow and differentiate into macrophages once they migrate to tissues.

Correct Answer: B

Rationale: The correct answer is B: Red blood cell. Red blood cells contain hemoglobin, a protein that binds to oxygen in the lungs and carries it to tissues throughout the body. White blood cells (A) are responsible for fighting infections, platelets (C) help with blood clotting, and plasma (D) is the liquid component of blood that carries nutrients and waste products. Thus, red blood cells are the only cells specifically designed to transport oxygen, making them the correct choice.

Correct Answer: A

Rationale: The correct answer is A: Ionic bond. In KCl, potassium (K) is a metal and chlorine (Cl) is a nonmetal. Ionic bonds form between a metal and a nonmetal through the transfer of electrons. In KCl, potassium donates an electron to chlorine, resulting in the formation of K+ and Cl- ions, which are held together by electrostatic forces. Covalent bonds (choice B) involve the sharing of electrons between two nonmetals, which is not the case in KCl. Hydrogen bonds (choice C) occur between molecules with hydrogen and electronegative atoms like oxygen or nitrogen, not between ionic compounds. Polar covalent bonds (choice D) involve unequal sharing of electrons between nonmetals, which is not the case in KCl where there is a complete transfer of electrons.