MIDTERMs ANAPHY - Lec Nervous system

Central Nervous System (CNS) and Peripheral Nervous System (PNS)

What are the two main divisions of the nervous system?

Brain, spinal cord, and nerves

What makes up the nervous system?

It acts as the body’s command and communication center

What is the main role of the nervous system?

sensation

Gathering information from the environment and internal body

integration

Processing and interpreting sensory input

motor output

Triggering actions like muscle movement

Managing voluntary and involuntary activities

What does coordination and control involve?

Consciousness, memory, learning, emotions

What are higher mental functions?

neurons

Nerve cells; basic units of the nervous system

3 parts of a neuron

Cell body, dendrites, axon

Function of dendrites

Carry impulses toward the cell body

Function of axon

Carries impulses away from the cell body

myelin sheath

Fatty covering that speeds up signal transmission

Sensory neurons function

Carry info from receptors to CNS

Motor neurons function

Carry commands from CNS to muscles/glands

Interneurons function

Connect neurons within the CNS

Multipolar neuron

One axon, many dendrites

Bipolar neuron

One axon, one dendrite

Pseudounipolar neuron

One process that splits; sensory in humans

neuroglia

Support cells for neurons

Function of neuroglia

Support, protect, nourish neurons

Function of myelin

Speeds up nerve signals

Nodes of Ranvier

Gaps in myelin where impulses jump

demyelination

Loss of myelin causing nerve problems

Receives, processes, and sends responses

What does the CNS do?

Movement, internal regulation, thinking, memory

What functions does it control?

CNS (Central Nervous System)

brain’s role

Control center for thought, memory, movement

3 major brain parts

Cerebrum, cerebellum, brainstem

Function of cerebrum

Thinking, memory, consciousness

4 lobes of cerebrum

Frontal, parietal, temporal, occipital

Frontal lobe function

Movement, decision-making

Parietal lobe function

Touch and sensory perception

Temporal lobe function

Hearing, memory, smell

Occipital lobe function

Vision

Language, logic, right body

Left hemisphere controls?

Creativity, spatial skills, left body

Right hemisphere controls?

Function of cerebellum

Balance, coordination, posture

Function of brain

Controls breathing, heart rate, reflexes

Function of spinal cord

Transmits signals and controls reflexes

31 segments

How many spinal segments?

meninges

Protective layers of brain and spinal cord

3 layers of meninges

Dura mater, arachnoid mater, pia mater

Function of CSF

Cerebrospinal Fluid

Cushion, protect, transport nutrients

BBB

Blood-Brain Barrier

Selective filter protecting brain from harmful substances

All nerves outside CNS

What is the PNS?

Peripheral Nervous System

Connects CNS to body

Function of PNS?

Peripheral Nervous System

Sensory nerves

Carry info to CNS

Motor nerves

Carry commands from CNS

Cranial nerves

Components

12 pairs from brain

Spinal nerves

Components

31 pairs from spinal cord

Ganglia

Components

Clusters of neuron cell bodies

Somatic Nervous System

: Function

Controls voluntary movements

Autonomic Nervous System

: Function

Controls involuntary processes

Sympathetic Division

: Role

Fight or flight

Parasympathetic Division

: Role

Rest and digest

Enteric Nervous System

: Function

Controls digestion