1. Today you will:
review science skills (variables, graphing)
define homeostasis and give examples
compare the nervous system and the 
endocrine system
look at parts of the nervous system

2. Unit 1 - Systems Regulating Change in Human Organisms
Homeostasis
- is the process by which a constant internal environment is 
maintained despite changes in the external environment.
This is crucial for life to exist.
The following diagram shows a homeostatic control system.
monitor
Coordinating
centre
Normal
Range
monitor
Adjustment
Regulator

3. Nervous System Endocrine System
By working together, the nervous and endocrine systems 
help us react to changes in the internal and external 
environment and maintain homeostasis.
Nervous System  Endocrine System
Release electric impulses  Releases chemical messengers (hormones)
Highly organized  Scattered glands with no anatomical
  connections
Systems built for speed;  Generally slower actions with some
Swift reactions to a stimulus  exceptions; have more prolonged
that is short lasting  effects
Enables continual rapid  Regulates activities which require
Adjustments to environmental  more sustained adaptation to change
change  (ex., growth , sexual maturation)
Compare to messages being sent  Compare to messages being sent
by telephone wire  by a mailing system.

4. These two systems co-ordinate activities:
1) The nervous system can stimulate/inhibit secretions of different cells.
2) Hormones can stimulate/inhibit the flow of nerve impulses.

5. Activities of the Nervous System
a) Reception: of stimuli and conduction to the central nervous system (CNS)
b) Interpretation: of impulses sent to CNS followed by decisions made in the light of remembered information
c) Sorting : of impuses and setting priorities for action upon them
 ex., insignificant - ignored
  sifnificant - acted upon
d) Transmission : of the impulses to the motor units which carry 
out appropriate actions; impulses are messages sent along neurons

6. Parts of the Nervous System a) Central Nervous System (CNS)
 - brain and spinal cord
 - coordinates, directs activities of the body

7. b) Peripheral Nervous System (PNS)
 - Nerves (outside the brain and spinal cord)
 - Information carried from sensory and internal organs 
 (ex., eye, ear, nose, ect.)
 - Carry impulses to create reactions by the muscles and 
 glands
 - Includes the autonomic nervous system (ANS) and  somatic nervous system (SNS)

8. Autonomic Nervous System
 - involuntary
 - controls the parts that act without our thinking about  them 
 (ex., stomach, intestines, glands)
 - prepares the body for emergencies and returns them to 
 normal after, its effects are exactly like adrenaline  secretion 
 from the adrenal medulla (sympathetic/parasympathetic)
Somatic Nervous System
 - voluntary
 - controls skeletal muscles, bones, skin

9. These are a Few of My Homeostatic Things
My heartbeat is racing
My breathing is heavy
Cold Clammy hands
And peristalsis ceases
My pupils are dilated
My stomach’s in knots
These are a few of my sympathetic things!
Glucose is flowing
My legs are like noodles
Alarm bells, school bells
Feeling tensile and nervous
I feel I can fly with a moon on my wings
Dogs with long nails make for deep crimson gashes
Moisture dries up in my throat and eyelashes
Jumping the fence with a high bounding spring
When the dog bites
When the bee stings
When I’m feeling mad
I simply remember my homeostatic things and then I don’t do so bad.
I empty my bladder
My pupil constrictions
Adrenaline settles
As do my blood flow restrictions
Kidney’s begin function
As calmness begins
These are a few of my parasymp things!
Pink colored blushes
Normal breathing gurgles
Alarm bells, school bells
I attract restful oogles
I don’t feel like flying with a moon on my wings.
The danger now passes with low glucose gushes
Moisture wells up in my throat and eyelashes
Jumping the fence is not my new thing
These are a few of my parasymp things! 

10. Nervous System Somatic Autonomic nerves nerves Central Nervous System
Peripheral Nervous System
Somatic
nerves
Autonomic
nerves
Brain  Spinal cord
sensory motor sympthetic parasympathetic

11. 1. Which statement is the best description of negative feedback?
Quick Review
1. Which statement is the best description of negative feedback?
a) A series of receptors that respond to changes in the internal environment of the body 
by inhibiting the release of hormones.
b) A control system that prevents imbalances in the body by compensating for any 
changes with a new change in the opposite direction.
c) A mechanism that responds to changes in the internal and external environments of 
hte body by stimulating the release of hormones.
d) A biological system that prevents the body from responding to changes in the 
external environment, releasing hormones, or using nerves to shut down organs.
2. How are the nervous system and endocrine system similar?
How are they different?
3. Differentiate between the peripheral nervous system and the central nervous 
system.