neurotransmitters send chemical messages across the gap between one neuron and another through which of the following structures

ATI TEAS 7

TEAS 7 Science Practice Test

1. Neurotransmitters send chemical messages across the gap between one neuron and another through which of the following structures?

A. Schwann cell
B. ganglion
C. synapse
D. axon

Correct answer: C

Rationale: Neurotransmitters send chemical messages across the gap between one neuron and another through a structure called the synapse. The synapse is a specialized junction where the axon of one neuron meets the dendrite or cell body of another neuron. Neurotransmitters are released from the axon terminal of the presynaptic neuron and travel across the synaptic cleft to bind to receptors on the postsynaptic neuron, transmitting the signal between the two neurons. Choice A, Schwann cell, is incorrect as Schwann cells are responsible for producing myelin sheath around axons in the peripheral nervous system, not for transmitting neurotransmitters between neurons. Choice B, ganglion, is incorrect as ganglia are clusters of nerve cell bodies outside the central nervous system and do not directly participate in the transmission of chemical messages between neurons. Choice D, axon, is incorrect as the axon is a long, slender projection of a neuron that conducts electrical impulses away from the cell body and towards the axon terminals, where neurotransmitters are released into the synapse, but it is not the structure across which neurotransmitters travel to communicate between neurons.

2. What is the term for the tiny particles that make up atoms?

A. Protons
B. Electrons
C. Neutrons
D. Subatomic particles

Correct answer: D

Rationale: The correct answer is 'Subatomic particles.' Subatomic particles are the tiny components that constitute atoms, including protons, neutrons, and electrons. Protons and neutrons are located in the nucleus of an atom, while electrons revolve around the nucleus. Choices A, B, and C specifically refer to individual subatomic particles but do not encompass the complete range of particles within an atom.

3. Which hormones are responsible for stimulating the development of sex organs and secondary sex characteristics during puberty?

A. Growth hormone
B. Testosterone (in males) and Estrogen (in females)
C. Insulin
D. Thyroid hormone

Correct answer: B

Rationale: Testosterone and estrogen are the primary sex hormones responsible for the development of male and female sex organs, respectively, and the emergence of secondary sex characteristics during puberty. Growth hormone, insulin, and thyroid hormone do not directly influence the development of sex organs and secondary sex characteristics during puberty. Growth hormone primarily regulates growth and metabolism, insulin regulates blood sugar levels, and thyroid hormone controls metabolism and energy levels. Therefore, choices A, C, and D are incorrect for this question.

4. What is the common name for the compound CH₃COOH?

A. Acetic acid
B. Formic acid
C. Butyric acid
D. Propionic acid

Correct answer: A

Rationale: The compound CH₃COOH is commonly known as acetic acid. Acetic acid is a clear, colorless liquid with a sour taste and a pungent smell. It is a weak acid found in vinegar and is used in the production of various chemicals. Formic acid, butyric acid, and propionic acid are different organic acids with distinct chemical structures and properties, but they are not the common name for the compound CH₃COOH.

5. Which type of muscle is characterized by voluntary control and is responsible for body movement?

A. Cardiac muscle
B. Smooth muscle
C. Skeletal muscle
D. Connective tissue

Correct answer: C

Rationale: The correct answer is skeletal muscle. Skeletal muscle is characterized by voluntary control, meaning it is under conscious control. It is responsible for body movement, such as walking, running, and lifting objects. Cardiac muscle is involuntary and found in the heart, while smooth muscle is also involuntary and found in organs like the intestines. Connective tissue is not a type of muscle but rather a type of tissue that provides support and structure in the body.