1. Coordination and Control
Human Regulation
Coordination and Control

2. Regulation in Humans Controlled by 2 systems
Nervous System - electrical
Endocrine System – chemical
Both systems respond to and send messages throughout the body

3. Central and Peripheral
Human Nervous System
Central and
Peripheral

4. A General Sense…

5. An Overview of the Nervous System:
Peripheral Nervous System
Central Nervous System
-Brain
-Spinal Cord
Sensory Neurons
-carry messages towards spinal cord from sensory receptors
Motor Neurons
-carry signals away from CNS
Somatic System: Voluntary Nerves
--neurons control skeletal muscles
Autonomic System:
Visceral, Involuntary
--heart, blood vessels, digestive organs, smooth muscle
Sympathetic Division
--“fight or flight”
--activated by stress
Parasympathetic Division:
--Routine

6. Nervous System Cells Called neurons
Neurons axons so they can transmit signals. Many neurons together are called a nerve.

7. Anatomy of a Neuron Cell body – main part
Dendrite – receives stimulus from other neurons
Axon – one long branche from cell body, sends the signal out
Synapse – gap between neurons; between the axon of 1 neuron and the dendrite of a 2nd neuron

8. Anatomy of a Neuron

9. Central Nervous System (CNS)
BRAIN
About 100 billion neurons
12 pairs of cranial nerves are connected to the human brain

10. Parts of the Brain Cerebrum – for voluntary activities of the body
Cerebellum – for coordinating body movements
Brain stem – connects brain and spinal cord
2 parts:
Medulla oblongata and Pons – controls internal organs

11. Spinal Cord Starts at the medulla oblongata (in the brain)
31 pairs of spinal nerves branch out to the body
Spinal Reflexes: these don’t go to the brain, instead they go to the spinal cord—
Ex. patellar reflex
Spinal Cord

12. Reflexes An automatic reaction to some sense message, like pain
Don’t need to think or make decisions about something
The information gets processed in your spinal cord
Your muscles begin to react immediately even before your brain gets the news of what’s happening.
This is called a reflex arc

13. Reflex Arc Begins at a receptor Travels to the spinal cord
Sensory neurons in the skin receive a stimulus
Travels to the spinal cord
Ends at an effector
A muscle or gland that reacts to the stimulus
Usually a motor neuron

14. Draw a Reflex Arc

15. Peripheral Nervous System (Motor and Sensory) Motor Division: signals away from CNS
Somatic nervous system is for voluntary muscle control. These neurons control the skeletal muscles….
Autonomic nervous system is automatic or involuntary
Control of heart rate, respiration, blood pressure, smooth muscle, etc.
This has 2 separate divisions: sympathetic and parasympathetic

16. Autonomic: Sympathetic Division & Parasympathetic Division
Sympathetic: Activated by physical or emotional stress “Fight or Flight” response.
Parasympathetic: Routine life, conserves energy, heart rate lowers, digestive organs back to normal.

17. Autonomic NS: Parasympathetic and Sympathetic Controls

18. Peripheral Nervous System Sensory Division
Sensory neurons carry messages toward the CNS from sensory receptors all over body.
Sensory receptors are in sense organs, such as eyes, ears, mouth, nose, skin… and different regions of the brain respond to different signals.

19. Transmission of a Signal
Think of it as dominoes
1st – send the message
Knock down the 1st domino
2nd – move the message along
Dominoes start to fall
3rd – reset the nerve
Line the dominoes back up

21. How does the electrical wave jump the gap?
Neurotransmitters
Chemicals released by the end of the axons that can flow across the synapse and bind to the dendrite of another neuron.
Lock and Key method

22. Nervous System Disorders
Cerebral Palsy – affect the ability to control body movements
Alzheimer’s – progressive degenerative disease; lose memory and ability to think, speak, etc.
Multiple Sclerosis – cells in the brain and spinal cord do not function normally.
Wide variety of symptoms

23. The Endocrine System

24. Endocrine System
A set of glands that produce hormones-- chemical messengers that circulate in the blood

25. Hormone
Chemical messengers produced by the endocrine glands and circulated in the blood
Similar to neurotransmitters in that they are also messengers
Slower communication system, but with longer lasting effects

26. Endocrine System

27. Hypothalamus Brain region that controls the pituitary gland
Controls homeostasis – the bodies ability to remain at a status quo level

28. Pituitary Gland
The endocrine system’s gland that controls the other endocrine glands
Called the “master gland”
Located at the base of the brain and connects to the hypothalamus
Controls thirst by controlling the amount of water in the body’s cells
Controls female contractions, and tells the mammary glands to produce milk for newborns
May control grooming habits, companionship, and sexual behavior
Controls the flow of the human growth hormones – dwarfism and gigantism

30. Thyroid Gland
Endocrine gland that helps regulate the energy level in the body
Located in the neck
controls body temperature
Controls metabolism – our body’s ability to transform the food we eat into usable energy
Overactive- Behaviors may include excitability, insomnia, ADD, agitation, difficulty focusing
Reduced Activity- Behaviors may include sleepiness, reduced muscle tone, overweight

32. Adrenal Gland
Endocrine glands that help to arouse the body in times of stress
Located just above the kidneys
Release epinephrine (adrenaline) and norepinephrine (noradrenaline)
Increase heart rate, blood pressure, and blood sugar

34. Pancreatic Gland
Regulates the level of blood sugar (insulin) in the blood
Insulin is needed in the body to break down sugars in the body
Too much insulin in the body devours all of the sugar in the blood. Behaviors exhibited include sluggishness and inattentiveness.

35. Too little insulin causes a buildup of sugar in the blood and makes the kidneys use a lot more water to flush it out of the body. The extra water needed to flush the sugar comes from surrounding cells, which in turn dehydrates them and leaves them vulnerable to infection and poisons.

37. Sex Glands
Ovaries (females) and testes (males) are the glands that influence emotion and physical development.
Testosterone – primary male hormone
Estrogen – primary female hormone
Males and females have both estrogen and testosterone in their systems.

38. Gonads Testicles – release androgens (male hormones)
Ovaries – release estrogens (female hormones)
The presence of these chemicals influence male and female reproductive characteristics.

39. Maintaining Homeostasis
Homeostasis is the maintenance of a stable internal state within an organism.
Organisms detect changes in their environment and respond to these changes in a variety of ways. 
A feedback mechanism occurs when the level of one substance influences the level of another substance or activity of another organ.

40. Feedback Mechanisms Three parts of the mechanism
Sensor – something that can detect a change
Ex. Structures in the brain detect change in CO2 levels
Control Unit – something that knows what the correct level should be
Ex. Information in the brain is preset for the correct CO2 level
Effector – something to take the instructions and make changes
Ex. Muscles in the chest used for breathing

41. Feedback Mechanisms
Positive feedback - designed to accelerate or enhance the output created by a stimulus that has already been activated.
Designed to push levels out of normal ranges.
Example is the release of oxytocin to intensify the contractions that take place during childbirth.
The more oxytocin, the greater and more frequent the contractions, which in turn produces more oxytocin

42. Feedback Mechanisms
Negative feedback – process in which a stimulus produces a response that opposes the original stimulus.
Ex. Blood sugar regulation
An increase in blood sugar level triggers the release of the hormone insulin by the pancreas
the hormone insulin lowers blood sugar level restoring the body to its original blood glucose level in two major ways:
it increases the ability of body cells to take in glucose from the blood
it converts blood glucose to the compound glycogen -- this compound is also called animal starch and is stored in our liver and muscles
A decrease in blood sugar levels triggers the release of the hormone glucagon by the pancreas
It causes the liver to release glucose into the blood to regulate blood sugar levels

44. Regulation Disorders Endocrine System
Diabetes – interruption of the feedback system that controls blood sugar.
Type I – born with it
Controlled by insulin injections
Type II – acquired
Usually occurs in older people
May be controlled with diet