Skip to main content
Ch. 12 Nervous Tissue
Martini - Fundamentals of Anatomy & Physiology 11th Edition
Martini, Nath, Bartholomew11th EditionFundamentals of Anatomy & PhysiologyISBN: 9780136874089당신이 사용하는 게 아니라요?교과서 변경
모든 교과서Martini, Nath, Bartholomew 11th EditionCh. 12 Nervous Tissue문제 24
12장, 문제 24

In multiple sclerosis, there is intermittent and progressive damage to the myelin sheath of peripheral nerves. This results in poor motor control of the affected area. Why does destruction of the myelin sheath affect motor control?

검증된 단계별 안내
1
Understand the role of the myelin sheath: The myelin sheath is a fatty layer that surrounds the axons of many neurons, including motor neurons. It acts as an insulator and increases the speed at which electrical impulses (action potentials) travel along the nerve fiber.
Recognize how myelin affects nerve signal conduction: Myelin enables saltatory conduction, where the action potential jumps between nodes of Ranvier (gaps in the myelin sheath). This process greatly speeds up the transmission of nerve signals compared to unmyelinated fibers.
Consider the effect of myelin damage: When the myelin sheath is damaged or destroyed, as in multiple sclerosis, the insulation is lost. This causes the electrical impulses to slow down or become blocked, reducing the efficiency and speed of nerve signal transmission.
Link impaired nerve conduction to motor control: Motor control depends on rapid and precise communication between the brain, spinal cord, and muscles. If nerve signals are delayed or disrupted due to myelin damage, muscle coordination and strength are compromised, leading to poor motor control.
Summarize the overall impact: Therefore, destruction of the myelin sheath affects motor control because it impairs the rapid and reliable transmission of electrical signals along motor neurons, which is essential for smooth and coordinated muscle movements.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Myelin Sheath and Its Function

The myelin sheath is a fatty layer that surrounds nerve fibers, acting as insulation. It enables rapid and efficient transmission of electrical signals along the nerve cells by facilitating saltatory conduction, which speeds up nerve impulse propagation.
추천 영상:
06:04
Functional Groups

Impact of Myelin Damage on Nerve Conduction

Damage to the myelin sheath disrupts the normal flow of electrical impulses, causing slower or blocked signal transmission. This leads to impaired communication between the nervous system and muscles, resulting in poor motor control and muscle weakness.
추천 영상:
가이드 코스
6:13
Control of Heart Rate

Motor Control and Neural Signaling

Motor control depends on precise and timely signals from the brain to muscles via motor neurons. When myelin is damaged, these signals become erratic or delayed, causing difficulties in coordinating muscle movements and leading to symptoms like weakness and loss of coordination.
추천 영상:
3:33
Levels of Control in the ANS
관련 실천
교과서 질문

What is the difference between temporal summation and spatial summation?

66
views
교과서 질문

Harry has a kidney condition that causes changes in his body's electrolyte levels (concentration of ions in the extracellular fluid). As a result, he is exhibiting tachycardia, an abnormally fast heart rate. Which ion is involved, and how does a change in its concentration cause Harry's symptoms?

588
views
교과서 질문

What factor determines the maximum frequency of action potentials that could be propagated by an axon?

818
views
교과서 질문

Describe the events that occur during nerve impulse transmission at a typical cholinergic synapse.

792
views