Cuestionario: Introduction to the Nervous System — 10 preguntas

1. What is the term for the part of the nervous system that includes the brain and spinal cord?

A. Central Nervous System

B. Peripheral Nervous System

C. Myelin Sheath

D. Gray Matter

Answer: (A)

Explicación

The correct answer is the 'Central Nervous System,' which consists of the brain and spinal cord. It is the main processing center of the nervous system, responsible for integrating sensory information and coordinating responses. The other options refer to different parts or features of the nervous system: the peripheral nervous system connects the CNS to the body; the myelin sheath insulates axons; and gray matter is a component of the CNS involved in processing.

2. What is the primary function of the myelin sheath in neurons?

A. To produce electrical impulses within neurons

B. To insulate axons and increase the speed of signal transmission

C. To transmit signals between neurons at synapses

D. To protect the neuron from external physical damage

Answer: (B)

Explicación

The myelin sheath acts as an insulator around the axon, enabling rapid saltatory conduction of electrical impulses. Its main role is not directly producing impulses, transmitting signals at synapses, or providing physical protection.

3. In neuron anatomy, which part of the neuron contains the nucleus and serves as the central processing unit of the cell?

A. Dendrites

B. Myelin sheath

C. Cell body (soma)

D. Axon

Answer: (C)

Explicación

The cell body, or soma, is the central part of the neuron that contains the nucleus and integrates incoming signals from the dendrites. Dendrites are extensions that receive signals, the axon transmits signals away from the cell body, and the myelin sheath insulates the axon to increase conduction speed. Therefore, the cell body is the correct answer.

4. Which parts of the nervous system are included in the Central Nervous System (CNS)?

A. Brain and spinal cord

B. All nerves outside the brain and spinal cord

C. Peripheral nerves and sensory neurons

D. The brain, spinal cord, and peripheral nerves

Answer: (A)

Explicación

The CNS comprises only the brain and spinal cord, which process information and coordinate responses. Peripheral nerves and sensory neurons are part of the PNS, not the CNS.

5. What is the primary role of sensory neurons in the nervous system?

A. To connect different neurons within the CNS for complex processing.

B. To transmit motor commands from the CNS to muscles and glands.

C. To process and interpret sensory information within the brain.

D. To carry sensory information from sensory receptors to the central nervous system.

Answer: (D)

Explicación

Sensory neurons are responsible for transmitting sensory information from sensory receptors located throughout the body to the central nervous system (CNS). They detect stimuli such as light, sound, or touch and relay this information for processing. Therefore, their primary role is to carry sensory information from receptors to the CNS.

6. Which of the following best describes the structure called 'gray matter' in the CNS?

A. Regions rich in myelinated axons responsible for communication

B. Regions rich in neuron cell bodies involved in processing and integration

C. Outer layer of the brain providing protection

D. Specialized nerve fibers responsible for reflexes

Answer: (B)

Explicación

Gray matter is composed mainly of neuron cell bodies and is involved in processing information, unlike white matter, which contains myelinated axons for communication.

7. What is the consequence of saltatory conduction facilitated by myelin and Nodes of Ranvier?

A. Slower transmission of nerve impulses

B. Faster transmission of nerve impulses along the axon

C. Transmission of signals through chemical means only

D. Decrease in the strength of electrical signals

Answer: (B)

Explicación

Saltatory conduction allows electrical impulses to jump between Nodes of Ranvier, speeding up transmission along myelinated axons.

8. What does the autonomic nervous system regulate?

A. Voluntary muscle movements like walking

B. Involuntary functions such as heart rate and digestion

C. Sensory information from skin and muscles

D. Reflex actions mediated by the spinal cord

Answer: (B)

Explicación

The autonomic nervous system controls involuntary functions like heart rate and digestion, unlike the somatic system which manages voluntary movements.

9. Which type of neuron is specialized for transmitting signals from sensory receptors to the CNS?

A. Motor neurons

B. Interneurons

C. Sensory neurons

D. Autonomic neurons

Answer: (C)

Explicación

Sensory neurons carry signals from sensory receptors toward the CNS, while motor neurons send signals away from the CNS to effectors.

10. Who was the scientist that contributed significantly to the understanding of neuron structure in the late 19th century?

A. Santiago Ramón y Cajal

B. Charles Darwin

C. Ivan Pavlov

D. Jean Piaget

Answer: (A)

Explicación

Santiago Ramón y Cajal was awarded the Nobel Prize in Physiology or Medicine in 1906 for his work detailing neuron structure, affirming the neuron doctrine.