Nervous & Endocrine

Systems

Unit 3 –

Modified PowerPoint from: Aneeq Ahmad -- Henderson State University. Worth Publishers © 2007

Goals for today

●Describe the nervous system and its

subdivisions and functions:

— central and peripheral nervous

systems

●Discuss the effect of the endocrine

system on behavior.

Nervous System

Central

Nervous

System

(CNS)

Peripheral

Nervous

System

(PNS)

Contains the

brain & the

spinal cord

In the “center”

of the body

The sensory

and motor

neurons that

connect the

CNS to the

rest of the

body.

Consists of all the nerve cells.

It is the body’s speedy, electrochemical communication system.

Central Nervous System (CNS)

The neural center of the

body – our body’s control

center

Super highway of nerves –

means of transmitting

messages between the brain

and the body

Peripheral Nervous System

Somatic Nervous System: controls voluntary

movements and communication to and from the

sense organs – you control these items, they don’t

“just happen”

Autonomic Nervous System: controls involuntary

functions or items that happen automatically within

our body – breathing, heartbeat, digestion, etc.

Autonomic Nervous System (ANS)

Sympathetic Nervous System: division of

the ANS that arouses the body, preparing

it to act/react in stressful situations and

expend energy

Parasympathetic Nervous System:

division of the ANS that calms the body,

conserving its energy & helping keep a

constant internal state

Autonomic Nervous System (ANS)

Sympathetic NS

“Arouses”

(fight-or-flight)

Parasympathetic NS

“Calms”

(rest and digest)

Kinds of Neurons

Sensory neurons (afferent) carry

incoming information from the sense

receptors to the CNS.

Interneurons act as messengers between

the two neurons & exist entirely within the

CNS…

Motor Neurons (efferent) carry outgoing

information from the CNS to muscles and

glands.

Sensory Neuron

(Bipolar)

Interneuron Neuron

(Unipolar)

Motor Neuron

(Multipolar)

How the 3

types of

neurons

communicate

The Endocrine SystemThe body’s “slow”

chemical communication

system.

Under “normal”

circumstances works in

parallel with the

parasympathetic NS to

sustain our basic

processes.

In a crisis works to

support the actions of the

sympathetic NS.

Example...While walking down the street, a man pulls

a gun on you…

the hormone epinephrine (adrenalin)

released into the bloodstream, sustaining

the body’s defensive reaction (“fight or

flight” response)

the endocrine system finishes what your

sympathetic NS started, keeping your

heart pounding and muscles tense, ready

for action

HormonesHormones are chemicals synthesized by the various

endocrine glands and secreted in the bloodstream…have

similar structure/function as many neurotransmitters

DIFFERENCES BETWEEN…

Hormones Neurotransmitters

Speed of transmission Slow (minutes) Fast (seconds)

Length of influence Last longer (wks) Brief duration

Method of transmission Bloodstream Neurons

*they are the same thing, just manufactured and located in different parts of the body

Neurotransmitters- made in neurons, in the nervous system

Hormones- made by gland, in the body and bloodstream

Pituitary Gland

“master gland”

Attempts to keep all endocrine

responses under tight control

Pituitary gland is under the

control of the

hypothalamus…sends out

hormone signals to the other

endocrine glands

Thyroid & Parathyroid Glands

Regulate metabolic, physical growth and development

and calcium rate.

Adrenal Glands & Pancreas

Adrenal glands regulate

“fight or flight” response &

metabolism. Pancreas

regulates level of sugar

(glucose) in the blood.

Gonads

Regulate bodily development (secondary sex

characteristics) and maintain reproductive organs

in adults (produce sperm/eggs).

produces

testosterone

produces

estrogen &

progesterone