NVCC BIO 102 Exam 4 Review Part 1 Ch 26

Nerve nets

Are nervous impulses spread over the entire body surface

Ganglia

clusters of neurons

nerve ladder

connects to paired muscles on each side of the body, allowing the worm to move rhythmically

Nerve cord

helps the animal coordinate movements

peripheral nervous system

carries information to or from the central nervous system

Central nervous system

interprets signals it receives from the peripheral nervous system

cell body

contains the nucleus, mitochondria, and other organelles.

Dendrites

are short, branched extensions that transmit information toward the cell body

axon

conducts nerve impulses away from the cell body

synapses

tiny gaps between dentrites and axons of different neurons

Myelin sheath

made of fatty neuroglia cells, coats sections of the axon and speeds neural impulses.

Sensory neurons

bring information from the body's organs toward the central nervous system

Inter neurons

receive signals from sensory neurons.The message is processed, and a signal is sent to a motor neuron.

motor neuron

conducts a message from the central nervous system to a muscle or gland, stimulating contraction or secretion

membrane potential

the voltage difference across a membrane

resting potential

is the membrane potential of a neuronnot sending signals

What is the concentration of K+ inside a neuron?

High

What is the concentration of Na+ inside a neuron?

Low

What is the concentration of K+ outside a neuron?

Low

What is the concentration of Na+ outside a neuron?

High

Sodium-potassium (Na+-K+) pumps

use energy from ATP to actively move Na+ out of the neuron and K+ into the neuron

action potential

a neural impulse; a brief electrical charge that travels down an axon

hyperpolarization

the membrane temporarily dips below resting potential, until the sodium-potassium pumps reestablish it.

Synaptic integration

determines the cell's response: if the majority of stimuli are excitatory, then the post synapticcell will likely initiate an action potential

central nervous system

integrates sensory information and coordinates the body's responses

peripheral nervous system

carries information between the central nervous system and the rest of the body

Somatic motor neurons

carry signals to voluntary muscles

Autonomic motor neurons

carry signals to involuntary muscles and glands

sympathetic nervous system

dominates under stress and emergencies

parasympathetic nervous system FUNCTION

decrease heart rate and breathing rate, constrict arteries

sympathetic nervous system FUNCTION

increase heart rate and breathing rate and dilate arteries

Gray matter

cell bodies and dendrites

White matter

myelinated axons

reflexes

Controlled by spinal cord without interacting with the brain

Forebrain consists of

cerebrum, Thalamus, Hypothalamus

Midbrain

relays info about voluntary movements from forebrain to spinal cord

Hindbrain consists of

medulla oblongata, pons, cerebellum

cerebrum

controls the qualities of what we consider the "mind.

limbic system

is also contained within the cerebrum. This"emotional center" of the brain is actually scattered through different brain areas.

hippocampus

is part of the limbic system responsible for forming long-term memories

amygdala

is part of the limbic system.It is responsible for forming emotions such as fear and pleasure

Neuronal plasticity

is the capacity of the nervous system to be remodeled, especially in response to its own activity. Also is essential to formation of memories

blood-brain barrier

protects the brain from extreme chemical fluctuations

meninges

are layered membranes that help protect the CNS

Cerebrospinal fluid

bathes and cushions thebrain and spinal cord

A

Cerebrum

B

Cerebellum

E

Pons

C

Thalamus

D

Hypothalamus

F

Medulla Oblongata