which of the following cardiac valves prevents blood from returning to the left ventricle of the heart

ATI RN

ATI Anatomy and Physiology

1. Which of the following cardiac valves prevents blood from returning to the left ventricle of the heart?

A. pulmonic
B. mitral
C. tricuspid
D. aortic

Correct answer: D

Rationale: The correct answer is the aortic valve. The aortic valve is located between the left ventricle and the aorta, preventing the backflow of blood into the left ventricle once it has been pumped out during systole. Choice A, pulmonic, is incorrect as it is associated with the right side of the heart. Choice B, mitral, is incorrect as it is the valve between the left atrium and ventricle. Choice C, tricuspid, is incorrect as it is located between the right atrium and ventricle.

2. Which of the following may indicate hypersecretion of thyroid hormone?

A. weight loss
B. Bradycardia
C. cold intolerance
D. lethargy

Correct answer: A

Rationale: Weight loss is a common symptom of hyperthyroidism, which is characterized by an excess secretion of thyroid hormone. This increased metabolic rate can lead to weight loss despite normal or increased appetite. Bradycardia (slow heart rate), cold intolerance, and lethargy are more commonly associated with hypothyroidism, where there is an insufficient production of thyroid hormone. Therefore, choices B, C, and D are incorrect in the context of hypersecretion of thyroid hormone.

3. Are the oral, nasal, orbital, and middle ear cavities in the dorsal cavity?

A. TRUE
B. FALSE
C. Not Sure
D. None of the above

Correct answer: B

Rationale: The correct answer is False. The oral, nasal, orbital, and middle ear cavities are actually part of the ventral cavity, not the dorsal cavity. The dorsal cavity contains the cranial and spinal cavities, while the ventral cavity includes the thoracic, abdominal, and pelvic cavities. Therefore, these structures are located in the ventral cavity, not the dorsal cavity. Choices A, C, and D are incorrect because these structures are not situated in the dorsal cavity.

4. Organ systems consist of organs, which consist of tissues.

A. True
B. False
C. Not Sure
D. None of the above

Correct answer: A

Rationale: The statement is true. Organ systems are made up of organs, which in turn are composed of tissues. Organs are structures made up of two or more types of tissues that work together to perform specific functions. Tissues, on the other hand, are groups of cells that work together to perform a specific function. Therefore, organs are made up of tissues, and organ systems consist of organs.

5. Ceroid pigments and lipofuscin accumulate with aging, impairing a cell's ability to withstand the damaging effects of oxygen free radicals.

A. TRUE
B. FALSE
C. Not Sure
D. None of the above

Correct answer: A

Rationale: The statement provided in the question is true. Ceroid pigments and lipofuscin are products of cellular damage and aging. These substances accumulate within cells over time and can impair cellular functions, including the ability to withstand the damaging effects of oxygen free radicals. Choice B, 'False,' is incorrect because the accumulation of ceroid pigments and lipofuscin does indeed impair a cell's ability to deal with oxidative stress. Choices C and D are also incorrect as the statement is true.