during normal breathing which muscle is the primary driver of inhalation by contracting and flattening to increase the volume of the thoracic cavity

ATI TEAS 7

TEAS 7 practice test free science

1. During normal breathing, which muscle is the primary driver of inhalation by contracting and flattening to increase the volume of the thoracic cavity?

A. Diaphragm
B. Intercostal muscles
C. Abdominal muscles
D. Pectoral muscles

Correct answer: A

Rationale: The diaphragm is the primary muscle responsible for inhalation during normal breathing. When it contracts, it flattens, increasing the volume of the thoracic cavity and creating a negative pressure that allows air to flow into the lungs. Intercostal muscles also play a role in expanding the chest cavity during inhalation, but the diaphragm is the main driver of the process. Abdominal muscles are primarily involved in exhalation by pushing the diaphragm upward to expel air from the lungs. Pectoral muscles are involved in movements of the arms and shoulders, not in breathing, making them incorrect choices for this question.

2. What is a primary function of red blood cells?

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

Correct answer: B

Rationale: The main function of red blood cells is to carry oxygen from the lungs to all the body's tissues and organs, where it is needed for cellular functions and metabolism. This process is essential for sustaining life and providing energy to cells. Choice A is incorrect because fighting infection is primarily done by white blood cells. Choice C is incorrect because antibody production is mainly carried out by specialized white blood cells. Choice D is incorrect as the primary role of red blood cells is not to transport waste, but rather to transport oxygen and some carbon dioxide.

3. Which term describes a position closer to the center of the body?

A. Distal
B. Proximal
C. Lateral
D. Medial

Correct answer: B

Rationale: The correct answer is B: Proximal. Proximal is used to describe a position closer to the center of the body. Distal, the incorrect choice, refers to a position farther away from the center. Lateral, another incorrect choice, indicates a position on the side of the body. Medial, also an incorrect option, describes a position towards the middle or midline of the body.

4. Find the lowest coefficients that will balance the following combustion equation: C H + O2 → CO2 + H2O

A. 1:5:5:2
B. 4:10:20:8
C. 2:9:10:4
D. 2:5:10:4

Correct answer: C

Rationale: To balance the combustion equation CxHy + O2 → xCO2 + y/2 H2O, we need to balance the carbon and hydrogen atoms. The balanced equation for the given combustion is: 2C H4 + 9O2 → 2CO2 + 4H2O. This means that the correct coefficients are 2:9:10:4, which corresponds to choice C. Choice A (1:5:5:2) does not balance the equation correctly, choice B (4:10:20:8) has excessive oxygen and does not balance the equation, and choice D (2:5:10:4) does not provide the correct ratio of oxygen to balance the equation.

5. Which property of matter refers to the force of gravity acting on an object?

A. Mass
B. Weight
C. Density
D. Volume

Correct answer: B

Rationale: Weight is the property of matter that refers to the force of gravity acting on an object. Mass is the amount of matter in an object, not affected by gravity. Density is the mass per unit volume of a substance, not directly related to gravity. Volume is the amount of space that an object occupies, not a measure of gravity's force.