TEAS Practice Test Science

Correct Answer: B

Rationale: The correct answer is B: Alveoli. Alveoli are tiny air sacs in the lungs where gas exchange occurs. Oxygen is taken in from the air and carbon dioxide is released into the air through the alveoli walls. The bronchi (A) are airways that carry air into the lungs but do not participate in gas exchange. The trachea (C) is the windpipe that connects the throat to the lungs and does not directly participate in gas exchange. The diaphragm (D) is a muscle that aids in breathing by contracting and relaxing to change the volume of the chest cavity but is not directly involved in gas exchange.

Correct Answer: D

Rationale: The correct answer is D because all of the statements are accurate regarding the microscopic anatomy of heart muscle. A: Cardiac muscle is indeed striated, short, fat, branched, and interconnected. B: Intercalated discs do anchor cardiac cells together and facilitate ion passage. C: The connective tissue endomysium serves as a support structure similar to tendons. Therefore, D is correct as all statements are true about the microscopic anatomy of heart muscle.

Correct Answer: A

Rationale: The correct answer is A: Femur. Long bones are characterized by their elongated shape, with the length exceeding the width. The femur, as the thigh bone, perfectly fits this description. It serves as a major weight-bearing bone and plays a crucial role in movement and support. Ribs and cranial bones (Choice B) belong to the category of flat bones. Sesamoid bones (Choice C) are small bones embedded within tendons. Vertebrae and hip bones (Choice D) are classified as irregular bones due to their complex shapes and structures.

Correct Answer: C

Rationale: The correct answer is C: molarity. Molarity is a concentration unit that depends on pressure because it is defined as the number of moles of solute dissolved in one liter of solution. Pressure can affect the volume of the solution, thus impacting the molarity. A: ppm (parts per million) and B: ppb (parts per billion) are mass-based concentration units and do not directly depend on pressure. D is incorrect because while molarity does depend on pressure, ppm and ppb do not.

Correct Answer: B

Rationale: The correct answer is B: Somatic. The somatic nervous system controls voluntary movements by sending signals from the brain to skeletal muscles. It is under conscious control. Autonomic (A), sympathetic (C), and parasympathetic (D) systems control involuntary functions like heart rate and digestion. These systems operate without conscious effort, making them unsuitable for controlling voluntary movements.