which of the following types of cells is primarily responsible for the destruction of old cells and invasive micro organisms

ATI RN

ATI Anatomy and Physiology

1. Which of the following types of cells is primarily responsible for the destruction of old cells and invasive micro-organisms?

A. Basophils
B. Eosinophils
C. B-cells
D. Macrophages

Correct answer: D

Rationale: Macrophages are a type of white blood cell that plays a crucial role in the immune system by engulfing and digesting cellular debris, foreign substances, microbes, cancer cells, and old or damaged cells. Basophils are primarily involved in allergic reactions and parasitic infections, eosinophils combat multicellular parasites and have a role in allergic reactions, and B-cells are responsible for producing antibodies. Therefore, the correct answer is macrophages as they are specialized in phagocytosis and removal of unwanted cells and microorganisms.

2. Signs of aging at the cellular level are

A. graying hair, waning strength, and wrinkles.
B. unrepaired DNA and abnormal proteins.
C. impaired cell division and the ability to break down and recycle worn cell parts.
D. a fatty liver and clogged blood vessels.

Correct answer: C

Rationale: The correct answer is 'impaired cell division and the ability to break down and recycle worn cell parts.' Aging at the cellular level involves reduced efficiency in cell division and the breakdown/recycling of cellular components, leading to functional decline. Choices A, B, and D are incorrect because they involve external physical manifestations or organ-specific issues rather than cellular-level changes associated with aging.

3. Which part of the brain regulates heart rate, respiratory rate, and blood pressure?

A. Corpus Callosum
B. Medulla Oblongata
C. Pituitary Glands
D. Pineal Glands

Correct answer: B

Rationale: The correct answer is the Medulla Oblongata. This part of the brain is responsible for regulating essential autonomic functions such as heart rate, respiratory rate, and blood pressure. The Corpus Callosum is responsible for connecting the left and right hemispheres of the brain, not for regulating these vital functions. The Pituitary Glands and Pineal Glands are part of the endocrine system and are not directly involved in regulating heart rate, respiratory rate, and blood pressure.

4. Which of the following is a result of stimulation of the sympathetic nervous system?

A. decreased blood flow to the skeletal muscles
B. increased cardiac output
C. decreased respiratory rate
D. increased urinary output

Correct answer: B

Rationale: Stimulation of the sympathetic nervous system leads to an increase in cardiac output. When the sympathetic nervous system is activated, it causes the heart to beat faster and with more force, leading to an increased cardiac output. Choices A, C, and D are incorrect because the sympathetic nervous system does not cause decreased blood flow to the skeletal muscles, decreased respiratory rate, or increased urinary output.

5. 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.