the above experimental design description is an example of which of the following types of experiments

ATI TEAS 7

TEAS 7 Science Practice Test

1. The above experimental design description is an example of which of the following types of experiments?

A. field experiment
B. natural experiment
C. controlled experiment
D. observational study

Correct answer: C

Rationale: The above experimental design description involves the manipulation of an independent variable (light exposure) to observe its effects on the dependent variable (plant growth) under controlled conditions. In a controlled experiment, researchers actively manipulate one or more variables while keeping all other variables constant to establish cause-and-effect relationships. Choice A, a field experiment, typically takes place in a real-world setting but still involves manipulation and control of variables. Choice B, a natural experiment, involves observing naturally occurring differences in variables without researcher intervention. Choice D, an observational study, does not involve manipulation of variables, making it different from the described experimental design.

2. What type of reaction is represented by the following equation: 2C₆H₁₄ + 19O₂ → 12CO + 14H₂O?

A. Substitution reaction
B. Acid-base reaction
C. Enzyme reaction
D. Combustion reaction

Correct answer: D

Rationale: The given chemical equation represents a combustion reaction. Combustion reactions involve the burning of a hydrocarbon (C₆H₁₄) in the presence of oxygen (O₂) to produce carbon monoxide (CO) and water (H₂O). Combustion reactions typically release heat and light energy. In this case, the reactants are a hydrocarbon and oxygen, resulting in the formation of carbon monoxide and water. Choices A, B, and C are incorrect because the reaction does not involve substitution, acid-base reactions, or enzyme catalysis. Combustion reactions are characterized by the rapid combination of a substance with oxygen, leading to the production of heat and light energy.

3. What is the structure and function of elastic arteries?

A. They are the smallest arteries and constrict and dilate frequently.
B. They are medium-sized arteries that distribute blood to various organs.
C. They are the largest arteries and stretch and recoil to accommodate blood pressure changes.
D. They are thin-walled arteries that supply blood to the capillaries.

Correct answer: C

Rationale: The corrected answer is C. Elastic arteries, like the aorta, are the largest arteries in the body. They possess elastic fibers in their walls, allowing them to stretch and recoil in response to the pulsatile nature of blood flow from the heart. This elasticity helps to maintain blood pressure by absorbing the pressure waves generated by the heart's contractions and ensuring continuous blood flow to the organs. Choices A, B, and D are incorrect because elastic arteries are not the smallest arteries, do not constrict and dilate frequently, are not medium-sized arteries for distributing blood to various organs, and are not thin-walled arteries supplying blood to capillaries. Elastic arteries have a specific structure and function related to their ability to accommodate blood pressure changes due to their elastic properties, which is essential for the cardiovascular system's proper functioning.

4. Which of the following lists of joint types is in the correct order for increasing amounts of permitted motion (least mobile to most mobile)?

A. Hinge, condyloid, saddle
B. Saddle, hinge, condyloid
C. Saddle, condyloid, hinge
D. Hinge, saddle, condyloid

Correct answer: A

Rationale: The correct order of joint types, from least mobile to most mobile, is hinge, condyloid, saddle. A hinge joint allows movement in one plane (like a door hinge), a condyloid joint allows movement in two planes but not rotation (like the wrist), and a saddle joint allows movement in multiple directions (like the thumb). Choice A, 'Hinge, condyloid, saddle,' is the correct sequence as it accurately represents the order of increasing permitted motion in joints. Choices B, C, and D are incorrect because they do not follow the correct order of joint types from least mobile to most mobile as required by the question.

5. What is the primary function of red blood cells?

A. To transport nutrients
B. To transport oxygen
C. To fight infection
D. To produce antibodies

Correct answer: B

Rationale: The correct answer is B: To transport oxygen. Red blood cells play a crucial role in carrying oxygen from the lungs to all the tissues and organs in the body. This oxygen transport is essential for cellular respiration, where oxygen is used in the production of energy. Red blood cells do not primarily transport nutrients, fight infection, or produce antibodies. Choice A is incorrect because while red blood cells do carry some nutrients, their primary function is to transport oxygen. Choice C is incorrect because immune cells, not red blood cells, are responsible for fighting infections. Choice D is incorrect as antibody production is mainly carried out by specialized white blood cells, not red blood cells.