Transcript What Are the Major Physiological Systems

What Are the Major
Physiological Systems ?
Nervous system – relays messages through
nerve impulses
 Responsible for controlling and
integrating the other systems of the body
 Neurons are the basic units
 Endocrine system – glands which secrete
chemical messages (hormones)

What Are the Major Parts of a
Neuron ?
Dendrites – receive information
 Cell body – generates electrical signals or
action potentials
 Axon – transmits signals at the synapse by
way of neurotransmitters

Neuron
Action Potential Movie
What Are the Major Divisions of
the Nervous System ?
Central nervous system (CNS)
 Brain and spinal cord
 Peripheral nervous system (PNS)
 Sensory and motor neurons that connect
the CNS to the rest of the body

CNS &
PNS
What Are Some of the Major
Features of the Brain’s Structure ?

The brain consists of 3 major parts
 Hindbrain – brainstem
 Midbrain – limbic system
 Forebrain – cerebral cortex
Hindbrain Graphic
Midbrain Graphic
Forebrain Graphic
What Are Some of the Major
Features of the Brain’s Structure ?

The brain is divided into a left hemisphere
and a right hemisphere
Left hemisphere movie
What Are Some of the Major
Features of the Brain’s Structure ?
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The corpus callosum connects the
hemispheres
Split Brain Movie
What Are the Major Divisions of
the Peripheral Nervous System ?
Somatic nervous system – connects CNS
with the skeletal muscles & senses
 Autonomic nervous system – connects CNS
with the internal organs and glands
 Sympathetic division – produces the
emergency reaction
 Parasympathetic division – returns body
to normal functioning

Endocrine System
What Are the Major Divisions of
the Endocrine System ?

Pituitary gland – the most influential gland
 Influenced by the hypothalamus
 Regulates growth
 Controls other glands
 Located on the underside of the brain
What Are the Major Divisions of
the Endocrine System ?
Thyroid gland – located below the larynx
 Produces thyroxin
 Regulates body’s metabolism
 Parathyroid glands – 4 pea-shaped organs in
the thyroid gland
 Regulates calcium in blood
 Related to excitability of nervous system

What Are the Major Divisions of
the Endocrine System ?
Pancreas – located in stomach area
 Regulates level of sugar in blood by
secreting insulin
 Gonads – ovaries & testes
 Produces secondary sex characteristics
 Adrenal glands – located above kidneys
 Helps with fight/flight/fright reaction
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