which of the following describes an experiment

ATI TEAS 7

ATI TEAS Science Test

1. Which of the following describes an experiment?

A. The final math grades for a group of students passing through each year of elementary school are examined.
B. The health trends of smokers in a small random sample are examined.
C. Citizens in a local community are surveyed to determine concerns related to the next election.
D. The effects of a new drug are tested on a group of participants.

Correct answer: D

Rationale: Option D describes an experiment because it involves testing the effects of a new drug on a group of participants. In an experiment, researchers intentionally manipulate an independent variable (in this case, the new drug) to observe its effects on a dependent variable (the participants' health outcomes). This method allows for establishing cause-and-effect relationships between variables, which is a key characteristic of experimental research design. Choices A, B, and C do not represent experiments. Choice A involves observational analysis of math grades, choice B involves observational analysis of health trends, and choice C involves a survey, none of which involve manipulating variables to establish cause-and-effect relationships.

2. Which statement is true about the pH of a solution?

A. A solution cannot have a pH less than 0.
B. A solution always has a pH of 7.
C. A solution's pH is not influenced by its chemical composition.
D. A solution with a pH of 14 is considered acidic.

Correct answer: A

Rationale: The pH scale ranges from 0 to 14, with 0 being the most acidic, 7 neutral, and 14 the most basic. A solution with a pH less than 0 would be outside the defined pH range, as 0 is the lower limit. Therefore, a solution cannot have a pH less than 0. Choice B is incorrect because a pH of 7 is considered neutral, not always the pH of a solution. Choice C is incorrect because a solution's pH is influenced by its chemical composition. Choice D is incorrect as a solution with a pH of 14 is considered highly basic, not acidic.

3. Which type of joint allows for the most movement?

A. Ball-and-socket joint (shoulder)
B. Hinge joint (elbow)
C. Fibrocartilaginous joint (wrists)
D. Suture joint (skull)

Correct answer: A

Rationale: A ball-and-socket joint allows for the most movement among the options provided. This type of joint is characterized by a rounded end of one bone fitting into a cup-like socket of another bone, allowing for a wide range of motion in multiple directions. The shoulder joint is a prime example of a ball-and-socket joint, enabling movements such as flexion, extension, abduction, adduction, and rotation. In contrast, a hinge joint (option B) like the elbow primarily allows for movement in one plane (flexion and extension). Fibrocartilaginous joints (option C) like the wrists have limited movement due to the presence of cartilage between the bones. Suture joints (option D) in the skull are immovable joints that provide structural support but do not allow for significant movement.

4. What is the name of the bone marrow cavity in the long bones where red blood cells are produced?

A. Periosteum
B. Diaphysis
C. Medullary cavity
D. Epiphysis

Correct answer: C

Rationale: The medullary cavity is the correct answer. It is the central cavity within the shafts of long bones where red bone marrow is located, responsible for the production of red blood cells. The periosteum is the outer layer of bone that provides nourishment and participates in bone repair. The diaphysis refers to the shaft of a long bone that contains yellow bone marrow. The epiphysis is the end of a long bone involved in joint articulation and contains red bone marrow in children for blood cell production.

5. What is the structure that connects the ovary to the uterus in the female reproductive system?

A. Urethra
B. Fallopian tube
C. Vagina
D. Cervix

Correct answer: B

Rationale: The fallopian tubes are the structures that connect the ovaries to the uterus in the female reproductive system. These tubes serve as a pathway for the egg to travel from the ovary to the uterus, where fertilization typically occurs. Options (A) Urethra, (C) Vagina, and (D) Cervix are not the structures responsible for connecting the ovary to the uterus, making them incorrect choices for this question.