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. Which of the following terms refers to a muscle that lengthens while another muscle contracts to produce movement?

A. Synergist
B. Agonist
C. Antagonist
D. Flexor

Correct answer: C

Rationale: The correct answer is 'Antagonist.' An antagonist muscle is a muscle that lengthens while another muscle (agonist) contracts to produce movement. The antagonist muscle relaxes to allow the agonist muscle to contract effectively. In this scenario, the antagonist muscle works in opposition to the agonist muscle, providing control and precision to movement. The other choices are incorrect because a synergist muscle assists the agonist muscle in performing a movement, an agonist muscle is the primary muscle responsible for generating movement, and a flexor muscle is a muscle that decreases the angle at a joint.

3. In the human skeleton, which of the following lists some of the vertebrae in descending order?

A. Atlas, axis, thoracic, lumbar, sacral, coccyx.
B. Axis, sacral, coccyx, atlas, lumbar, thoracic.
C. Thoracic, sacral, lumbar, axis, coccyx, atlas.
D. Coccyx, lumbar, axis, sacral, thoracic, atlas.

Correct answer: A

Rationale: The correct order of some of the vertebrae in the human skeleton in descending order is Atlas, Axis, Thoracic, Lumbar, Sacral, Coccyx. This sequence follows the typical arrangement from the top of the spine down towards the pelvis. Choice B is incorrect as it does not follow the descending order of vertebrae. Choice C is incorrect as it starts with Thoracic which is not the first vertebra in the descending order. Choice D is incorrect as it starts with Coccyx which is the last vertebra in the descending order.

4. Which cells myelinate neurons in the CNS?

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

Correct answer: D

Rationale: The correct answer is D, Oligodendrocytes. Oligodendrocytes are responsible for myelinating neurons in the central nervous system (CNS). Schwann cells, found in the peripheral nervous system, are responsible for myelinating neurons there. Astrocytes support and maintain the neuronal environment, while microglia function as immune cells in the CNS, participating in immune responses and cellular debris clearance. Therefore, choices A, B, and C are incorrect for myelination of CNS neurons.

5. The chemical equation below is unbalanced. When it is properly balanced, how many molecules of carbon dioxide (CO2) are produced for each molecule of propane (C3H8) in the reaction? 3C3H8 + 5O2 → 3CO2 + 4H2O

A. One Half.
B. Two.
C. Three.
D. Five.

Correct answer: B

Rationale: The balanced chemical equation for the combustion of propane is: 3C3H8 + 5O2 → 3CO2 + 4H2O. This equation shows that for every 3 molecules of propane (C3H8) consumed, 3 molecules of carbon dioxide (CO2) are produced. Therefore, when properly balanced, 3CO2 are produced for each molecule of propane used. Thus, the correct answer is B: Two. Choices A, C, and D are incorrect because they do not reflect the correct stoichiometry as determined by the balanced equation.