Practice Science TEAS Test

Correct Answer: B

Rationale: The correct answer is B: Malaria. Malaria is caused by a protozoan parasite called Plasmodium, which is transmitted through the bite of infected mosquitoes. Protozoan parasites are single-celled organisms that can cause various infectious diseases in humans. Measles (A), mumps (C), and mononucleosis (D) are caused by viruses, not protozoan parasites. Viruses are different from protozoa in terms of structure, replication, and mode of infection. Therefore, the correct choice is B as it aligns with the characteristic of being caused by a protozoan parasite.

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.

Correct Answer: B

Rationale: The correct answer is B: To provide structural support. The skeletal system functions to support the body, protect internal organs, allow movement, and produce blood cells. Structural support is a primary function as bones form the framework of the body. Red blood cell production occurs in the bone marrow, not the skeletal system directly (A). Nutrient transport primarily involves the circulatory system, not the skeletal system (C). Fat storage is not a function of the skeletal system; it is mainly stored in adipose tissue (D). In summary, the skeletal system's main function is to provide structural support for the body.

Correct Answer: A

Rationale: Estrogen is the correct answer because it is the hormone released by the ovaries to mature an egg. Estrogen plays a crucial role in the development of the ovarian follicle, promoting the growth and maturation of the egg. Luteinizing Hormone and Progesterone are also involved in the menstrual cycle but do not directly mature the egg. Testosterone is primarily produced in the testes and plays a role in male reproductive functions, not in egg maturation.

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.