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. What is the function of the cell membrane?

A. To protect the cell and control what enters and exits
B. To store energy
C. To produce proteins
D. To synthesize lipids

Correct answer: A

Rationale: The cell membrane, also known as the plasma membrane, serves as a protective barrier for the cell, separating the internal environment of the cell from the external environment. It is selectively permeable, meaning it controls the passage of substances in and out of the cell. This regulation of what enters and exits the cell is crucial for maintaining the cell's internal environment and ensuring proper functioning. Options B, C, and D are incorrect because storing energy, producing proteins, and synthesizing lipids are functions carried out by other cellular structures such as mitochondria, ribosomes, and endoplasmic reticulum, respectively, not the cell membrane.

3. What property of a substance refers to its ability to undergo a chemical change and form new substances?

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

Correct answer: C

Rationale: Reactivity is the property of a substance that describes its ability to undergo a chemical change and form new substances. Density (A), mass (B), and volume (D) are physical properties of a substance and do not directly relate to its ability to undergo chemical changes. Density is the measure of how much mass is contained in a given volume, mass is the amount of matter in an object, and volume is the amount of space an object occupies. Therefore, reactivity (C) is the correct answer as it specifically addresses the substance's ability to undergo chemical changes.

4. What is the structure that surrounds individual muscle fibers, providing support and aiding in the transmission of force generated during muscle contraction?

A. Tendon
B. Endomysium
C. Perimysium
D. Epimysium

Correct answer: B

Rationale: The endomysium is the connective tissue layer that surrounds individual muscle fibers, providing support and aiding in the transmission of force generated during muscle contraction. It is crucial for maintaining the structural integrity of muscle fibers and facilitating the transmission of force within them. Tendons (option A) connect muscles to bones, perimysium (option C) surrounds bundles of muscle fibers known as fascicles, and epimysium (option D) encases the entire muscle. The endomysium specifically targets the structure that directly supports and aids in force transmission within individual muscle fibers, making it the correct answer in this context.

5. Define the term 'velocity' in relation to motion.

A. Speed in a specific direction
B. Distance traveled in a given time
C. Rate of change of position
D. Acceleration due to gravity

Correct answer: A

Rationale: Velocity is a vector quantity that describes the speed of an object along with its direction of motion. Unlike speed, which is a scalar quantity focusing solely on the magnitude of motion, velocity considers both speed and direction. Therefore, the best definition of velocity is 'speed in a specific direction.' Choice B, 'Distance traveled in a given time,' is incorrect as it defines speed rather than velocity. Choice C, 'Rate of change of position,' is more aligned with the definition of velocity but lacks the specificity of direction. Choice D, 'Acceleration due to gravity,' is unrelated to the definition of velocity and refers to a different concept in physics.