how are the motor pathways of the ans arranged

ATI TEAS 7

ATI TEAS Science Practice Test

1. How are the motor pathways of the ANS arranged?

A. Single neuron from CNS to target organ
B. Two neurons, a pre-ganglionic and post-ganglionic neuron
C. Multiple neurons from CNS to target organ
D. Single neuron from CNS to peripheral ganglia

Correct answer: B

Rationale: The correct answer is B. The motor pathways of the autonomic nervous system (ANS) are organized with two neurons: a pre-ganglionic neuron that transmits the signal from the central nervous system (CNS) to a ganglion, and a post-ganglionic neuron that conveys the signal from the ganglion to the target organ. This dual-neuron pathway enables the integration and modulation of signals before reaching the target organ, allowing for a more sophisticated and adaptable control system. Choice A is incorrect as it describes a single neuron pathway, which is not characteristic of ANS motor pathways. Choice C is incorrect as it suggests multiple neurons from the CNS to the target organ, which is not the typical arrangement. Choice D is incorrect as it describes a single neuron pathway from the CNS to peripheral ganglia, which does not account for the ganglionic transmission in ANS motor pathways.

2. Bile, a yellowish-green fluid, is stored in the gallbladder and released into the small intestine during digestion. What is the primary function of bile in digestion?

A. Break down carbohydrates
B. Break down proteins
C. Emulsify fats
D. Neutralize stomach acid

Correct answer: C

Rationale: The primary function of bile in digestion is to emulsify fats. Bile contains bile salts that help break down large fat globules into smaller droplets, increasing the surface area for enzymes to work on and aiding in the absorption of fats in the small intestine. Choices A, B, and D are incorrect because bile's main role is not to break down carbohydrates or proteins, nor to neutralize stomach acid; rather, it primarily assists in the digestion and absorption of fats through emulsification.

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 of the following is the cardiac muscle layer that forms the bulk of the heart?

A. Endocardium
B. Epicardium
C. Fibrous skeleton
D. Myocardium

Correct answer: D

Rationale: The correct answer is D, Myocardium. The myocardium is the cardiac muscle layer that comprises the majority of the heart's muscle mass. It is responsible for the heart's contractions, allowing it to pump blood throughout the body. The endocardium is the innermost layer of the heart lining the chambers, while the epicardium is the outermost layer covering the heart. The fibrous skeleton provides structural support and serves as an attachment point for cardiac muscle fibers. Therefore, choices A, B, and C are incorrect as they do not represent the primary muscle layer of the heart.

5. A population refers to a group of organisms of the same:

A. Species living in the same area
B. Genus competing for resources
C. Kingdom inhabiting a specific biome
D. Phylum found throughout the world

Correct answer: A

Rationale: A population is defined as a group of organisms of the same species living in the same area and interacting with one another. Option A correctly describes this definition by specifying that the organisms are of the same species and share a common geographical location. Options B, C, and D are incorrect because they do not accurately define a population in biological terms. In this context, a population specifically refers to a group of organisms belonging to the same species, not higher taxonomic ranks like genus, kingdom, or phylum.