Neural and Hormonal Systems

1
Neural and Hormonal Systems

• Module 07

2
Neurons The Building Blocks of the Nervous
System

• Module 7 Neural and Hormonal Systems

3
Nervous System

• The electrochemical communication system of the
  body
• Sends messages from the brain to the body for
  movement
• Brings information to the brain from the senses

4
Neuron

• The basic building block of the nervous system --
  a nerve cell
• Neurons perform three basic tasks
• Receive information
• Carry the information
• Pass the information on to the next neuron

5
Neurons

• Neurons fire -- send an impulse down their
  length -- or they dont fire
• Neurons come in a variety of shapes, sizes, etc.

6
Parts of the Neuron
7
Parts of the Neuron - Dendrites
8
Parts of the Neuron - Soma
9
Parts of the Neuron - Axon
10
Parts of the Neuron Myelin Sheath
11
Parts of the Neuron - Terminals
12
Neural Communication The Neural Impulse

• Module 7 Neural and Hormonal Systems

13
Action Potential

• A brief electrical charge that travels down the
  axon of the neuron.
• A neural impulse
• Considered an on condition of the neuron

14
Refractory Period

• The recharging phase when a neuron, after
  firing, cannot generate another action potential
• Once the refractory period is complete the neuron
  can fire again

15
Resting Potential

• The state of a neuron when it is at rest and
  capable of generating an action potential
• The neuron is set and ready to fire

16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
All-or-None Principle

• The principle that if a neuron fires it will
  always fire at the same intensity
• All action potentials are of the same strength.
• A neuron does NOT fire at 30, 45 or 90 but at
  100 each time it fires.

20
Communication Between Neurons

• Module 7 Neural and Hormonal Systems

21
Synapse

• The tiny, fluid filled gap between the axon
  terminal of one neuron and the dendrite of
  another neuron
• The action potential cannot jump the gap

22
Neurotransmitters

• A chemical messenger that travels across the
  synapse from one neuron to the next
• Can influence whether the second neuron will
  generate an action potential or not

23
Neurotransmitters
24
(No Transcript)
25
(No Transcript)
26
(No Transcript)
27
Excitatory Effect

• A neurotransmitter effect that makes it more
  likely that the receiving neuron will generate an
  action potential (impulse)
• The second neuron is more likely to fire.

28
Inhibitory Effect

• A neurotransmitter effect that makes it less
  likely that the receiving neuron will generate an
  action potential (impulse)
• The second neuron is less likely to fire.

29
Neural Communication The Neural Chain

• Module 7 Neural and Hormonal Systems

30
Receptor Cells

• Specialized cells in the sensory systems of the
  body that can turn other kinds of energy into
  action potentials that the nervous system can
  process
• Receptor cells in the eye turn light into a
  neural impulse the brain understands.

31
Sensory Nerves

• Nerves that carry information to the central
  nervous system
• Connect the sense organs to the brain and spinal
  cord

32
Interneurons

• Nerve cells in the brain and spinal cord
  responsible for processing information related to
  sensory input and motor output

33
Motor Nerves

• Nerves that carry information from the central
  nervous system
• Carries messages from the brain and spinal cord
  to other parts of your body

34
A Neural Chain
35
A Neural Chain
36
A Neural Chain
37
A Neural Chain
38
A Neural Chain
39
The Structure of the Nervous System

• Module 7 Neural and Hormonal Systems

40
The Nervous System
41
Central Nervous System (CNS)

• The brain and spinal cord
• The brain is the location of most information
  processing.
• The spinal cord is the main pathway to and from
  the brain.

42
Spinal Cord
43
Divisions of the Nervous System
44
Peripheral Nervous System (PNS)

• The sensory and motor nerves that connect the
  central nervous system to the rest of the body
• Peripheral means outer region
• The system is subdivided into the somatic and
  autonomic nervous systems.

45
Divisions of the Nervous System
46
Somatic Nervous System

• The division of the peripheral nervous system
  that controls the bodys skeletal muscles
• Contains the motor nerves needed for the
  voluntary muscles

47
Divisions of the Nervous System
48
Autonomic Nervous System

• The division of the peripheral nervous system
  that controls the glands and muscles of the
  internal organs
• Monitors the autonomic functions
• Controls breathing, blood pressure, and digestive
  processes
• Divided into the sympathetic and parasympathetic
  nervous systems

49
Divisions of the Nervous System
50
Sympathetic Nervous System

• The part of the autonomic nervous system that
  arouses the body to deal with perceived threats
• Fight or flight response

51
Divisions of the Nervous System
52
Parasympathetic Nervous System

• The part of the autonomic nervous system that
  calms the body
• Brings the body back down to a relaxed state

53
Divisions of the Nervous System
54
The Sympathetic and Parasympathetic Divisions of
the Autonomic Nervous System
55
The Sympathetic and Parasympathetic Divisions of
the Autonomic Nervous System
56
The Sympathetic and Parasympathetic Divisions of
the Autonomic Nervous System
57
The Sympathetic and Parasympathetic Divisions of
the Autonomic Nervous System
58
The Sympathetic and Parasympathetic Divisions of
the Autonomic Nervous System
59
The Sympathetic and Parasympathetic Divisions of
the Autonomic Nervous System
60
The Sympathetic and Parasympathetic Divisions of
the Autonomic Nervous System
61
The Endocrine System

• Module 7 Neural and Hormonal Systems

62
Endocrine System

• One of the bodys two communication systems
• A set of glands that produce hormones-- chemical
  messengers that circulate in the blood

63
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

64
Pituitary Gland

• The endocrine systems gland that controls the
  other endocrine glands
• Called the master gland
• Located at the base of the brain and connects to
  the hypothalamus

65
Endocrine System
66
Thyroid Gland

• Endocrine gland that helps regulate the energy
  level in the body
• Located in the neck

67
Endocrine System
68
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)

69
Endocrine System
70
Pancreatic Gland

• Regulates the level of blood sugar in the blood

71
Endocrine System
72
Sex Glands

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

73
Endocrine System
74
Self Test pg. 137-38 1-11