which human body system is correctly matched with its function

ATI TEAS 7

ATI TEAS Science Test

1. Which human body system is correctly matched with its function?

A. Respiratory system; exchanges oxygen and carbon dioxide in the lungs.
B. Circulatory system; transports oxygen to cells and removes carbon dioxide.
C. Lymphatic system; produces antibodies that destroy virally affected or foreign cells.
D. Endocrine system; regulates hormones controlling bodily functions and metabolism.

Correct answer: B

Rationale: The circulatory system is responsible for the transportation of oxygen from the lungs to all the body's cells and tissues, as well as removing carbon dioxide from the cells and transporting it back to the lungs to be exhaled. This process is crucial for cellular respiration and the exchange of gases necessary for bodily functions. Choice B accurately matches the role of the circulatory system by describing its function of transporting oxygen to cells and removing carbon dioxide, which is essential for maintaining proper cellular activities. Choices A, C, and D are incorrect because they do not accurately match the body system with its function. The respiratory system primarily involves the exchange of gases in the lungs, not transportation to cells; the lymphatic system deals with immunity through the production of antibodies, not gas exchange; and the endocrine system's main function is hormone regulation, not the transport of gases.

2. Myelin sheath is a fatty substance that insulates and protects the long extensions of some nerve cells. It is produced by:

A. Schwann cells
B. Astrocytes
C. Neurons
D. Oligodendrocytes

Correct answer: A

Rationale: Schwann cells are indeed responsible for producing the myelin sheath in the peripheral nervous system. These cells wrap around axons to form the myelin sheath, which enhances the speed of nerve impulse conduction. In the central nervous system, oligodendrocytes are responsible for producing the myelin sheath. Astrocytes provide support and maintenance functions for neurons, while neurons are the nerve cells themselves and do not produce myelin. Therefore, the correct answer is Schwann cells as they are specifically involved in myelin production in the peripheral nervous system.

3. Which of the following is the base that will bind with cytosine?

A. Adenine
B. Cytosine
C. Guanine
D. Thymine

Correct answer: A

Rationale: Adenine is the correct answer as it is the base that binds with cytosine through hydrogen bonding in DNA, forming the A-T base pair. Cytosine always pairs with guanine to form the G-C base pair. Thymine pairs with adenine in DNA, not with cytosine.

4. What property of a substance remains constant regardless of changes in its shape or size?

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

Correct answer: A

Rationale: Mass is a measure of the amount of matter in an object and remains constant regardless of changes in its shape or size. Weight, density, and volume can all change depending on the conditions, but mass remains the same. For example, if you have a piece of clay and you shape it into a ball or flatten it into a pancake, the amount of clay (mass) will remain the same, even though the shape and size have changed. Weight is the force acting on an object due to gravity, which can vary depending on the gravitational pull. Density is the mass per unit volume, so it changes with variations in volume. Volume is the amount of space occupied by an object, which can change if the shape or size of the object is altered.

5. Which type of immunity does the MMR vaccine provide?

A. Artificial/active
B. Artificial/passive
C. Natural/active
D. Natural/passive

Correct answer: A

Rationale: The correct answer is A: Artificial/active. The MMR vaccine provides artificial/active immunity. It works by introducing a weakened or killed form of the virus to trigger the body's immune response, leading to the production of antibodies that offer long-lasting protection against measles, mumps, and rubella. Artificial immunity is obtained through medical intervention, such as vaccination, while active immunity involves the immune system's direct response to an antigen. Choices B, C, and D are incorrect because the MMR vaccine does not provide passive immunity nor is it acquired naturally; instead, it stimulates the body to actively produce its immune response.