Biology Chapter 10: The Nervous System I

Questions and Answers

What are two types of neural tissue?

Muscle Cells and Epithelial Cells

Connective Tissue and Epithelial Cells

Bone Cells and Fat Cells

Neuron and Neuroglia Cells (correct)

How many types of fibers does a neuron have?

Two

What do dendrites do?

Receive nerve impulses and transfer information to the body of the neuron

What does the axon do?

Carries nerve impulses away from the body of the neuron Signup and view all the answers

What is at the end of an axon?

Knobbed branches Signup and view all the answers

What is the myelin sheath?

An insulation around axons made of fatty material Signup and view all the answers

What are the Nodes of Ranvier?

Uninsulated spaces between myelin sheaths Signup and view all the answers

What are nerves?

Bundles of axons Signup and view all the answers

What is a synapse?

The small space between the knobs on an axon and another cell Signup and view all the answers

What are the two types of synaptic transfers?

Electrical and Chemical Signup and view all the answers

What is an electrical synaptic transfer?

Transfer of an electrical signal between neurons Signup and view all the answers

What is a chemical synaptic transfer?

Transfer involving neurotransmitters released at the synapse Signup and view all the answers

What happens when a neurotransmitter is released?

It diffuses across the synaptic cleft and triggers a nerve impulse Signup and view all the answers

Describe unipolar neurons.

Neurons with a single process extending from the cell body Signup and view all the answers

Describe bipolar neurons.

Neurons with two processes extending from both ends of the cell body Signup and view all the answers

Describe multipolar neurons.

Neurons with multiple processes from the cell body Signup and view all the answers

Describe sensory neurons.

Neurons that carry impulses from peripheral body parts to the brain or spinal cord Signup and view all the answers

Describe interneurons.

Neurons that transmit impulses within the spinal cord or brain Signup and view all the answers

Describe motor neurons.

Neurons that carry nerve impulses to effectors like muscles or glands Signup and view all the answers

Study Notes

Neural Tissue

Neuron: Fundamental unit of the nervous system, responsible for transmitting nerve impulses.
Neuroglia Cells: Support cells in the nervous system that produce myelin, facilitate communication between neurons, and maintain ionic balance.

Neuron Structure

Two types of fibers: Dendrites and axons, projecting from the neuron’s cell body.
Dendrites: Receive nerve impulses and carry information toward the neuron body.
Axon: Transmits nerve impulses away from the neuron body to other neurons or cells.

Axon Characteristics

Axon Terminals: Knobbed branches at the end of an axon that transmit signals to other cells.
Myelin Sheath: Insulating layer surrounding axons, composed of fatty material from Schwann cells; it enhances signal transmission efficiency by preventing impulse dissipation.

Nodes of Ranvier

Definition: Gaps in the myelin sheath that allow nerve impulses to jump, increasing conduction speed.

Nerves and Synapses

Nerves: Bundles of axons that transmit signals in the nervous system.
Synapse: The junction between an axon terminal and another neuron or cell, critical for electrochemical communication.

Types of Synaptic Transfers

Electrical Transfer: Direct transfer of electrical signals; prevalent in the heart and digestive system for maintaining rhythmic contractions.
Chemical Transfer: Involves neurotransmitters released from axon terminals, transmitting signals across synapses.

Neurotransmitter Function

Release Mechanism: Upon receptor binding, they generate a nerve impulse in the receiving cell. Following transmission, neurotransmitters are broken down or reabsorbed to terminate the signal.

Neuron Types

Unipolar Neurons: Single process extending from the cell body; primarily located outside the brain and spinal cord.
Bipolar Neurons: Two processes extending from each end; located in specialized sensory organs such as the eyes, ears, and nose.
Multipolar Neurons: Multiple processes from the cell body; primarily found in the brain and spinal cord.

Functional Neuron Categories

Sensory Neurons (Afferent): Transmit impulses from peripheral sensory receptors to the CNS; often unipolar.
Interneurons: Found in the CNS, transmitting signals between different parts of the brain and spinal cord; typically multipolar.
Motor Neurons (Efferent): Carry impulses from the CNS to effectors like muscles and glands; usually multipolar.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on the fundamentals of the nervous system with this flashcard quiz. Learn about neural tissue, neuronal fibers, and the specific functions of dendrites and axons. Perfect for students studying biology!