Transcript Chapter 29 Review

Chapter 29 Review
Section 29.1
• The nervous system (brain, spine, nerves) and
endocrine systems (glands that produce
hormones) allow for communication inside the
body
• These systems respond to a stimulussomething that causes a response or change in
the animal (e.g. sight, sound, smell, etc.)
Differences between the
communication systems
• Nervous system responds quickly and has shortterm effects.
• Endocrine system responds more slowly and
has long-term effects.
• Nervous system controls thoughts, movements,
and emotions.
• Endocrine system controls growth, development,
and response to the environment.
The Nervous System
• Divided into 2 parts:
• Central Nervous System(CNS)- brain and spinal
cord
• Peripheral Nervous System(PNS)- network of
nerves spread throughout the body (everywhere
except brain and spinal cord).
• PNS sends signals to CNS, which CNS
processes, then sends signal back to PNS to tell
the body what to do.
Section 29.2
• Neurons: cells that make up the nervous
system.
• Neurons store information and send
signals to the brain and throughout the
body.
• Neurons have 3 parts: dendrites (branchlike area at front of neuron), cell body (has
nucleus), and axon (long tail end of
neuron)
Movement of Signals Inside a
Neuron
• Resting potential is when the neuron is not active. The
inside of the neuron is negative, while the outside is
positive.
• A signal is picked up by the dendrites of the neuron, then
passes through the cell body and goes down the axon
until it reaches the axon terminal.
• The signal (or impulse) that goes through the neuron is
called an action potential.
• In an action potential, the inside of the neuron becomes
positive while the outside is negative (because sodium
moves into the neuron).
Neurotransmitters
• When the action potential reaches the axon
terminals (end of axon), it causes vesicles to
release chemical messengers
(neurotransmitters) into the synapse (the gap
between two neurons).
• The neurotransmitter goes through the gap and
binds to receptors on the other neuron. This
moves the signal (action potential) from the first
neuron to the second neuron.
Section 29.4
• CNS-brain and spinal cord-processes
information that comes from the rest of the body
(the PNS).
• CNS has interneurons that interact with other
nerves in the body.
• PNS sends signals from the body (e.g. muscles,
organs) to the CNS and then responds to signal
from the CNS.
• PNS has sensory neurons (detect stimuli) and
motor neurons (control muscles).
Peripheral Nervous System
• PNS is divided into somatic nervous
system (controls voluntary muscles) and
autonomic nervous system (controls
involuntary muscles).
• Somatic nervous system is used when you
raise your hand.
• Autonomic nervous system is used when
you are breathing.
Autonomic Nervous System
• This is divided into 2 parts:
• Sympathetic nervous system-controls fight
or flight response.
• Parasympathetic nervous sytem-calms the
body down after fight or flight response.
Section 29.5
• Changes in the brain can cause illness.
• If there are too many or too few
neurotransmitters, that can hurt the function of
the brain.
• Illnesses of the brain include schizophrenia and
depression.
• Brain can become dependent on a drug
(addiction), such that larger doses of the drug
are needed to cause a response (tolerance).
Section 29.6
• The Endocrine System is made of glands
that produce hormones.
• Hormones are chemical messengers that
enter the blood and travel through the
body.
• Hormones bind to receptors on target cells
to cause a response in the cell.
Control of Hormones
• The hypothalamus (small region inside the brain) is the
master regulator of the endocrine system.
• Hypothalamus sends releasing hormones to the pituitary
gland.
• The pituitary gland releases its own hormones as a
response.
• The hormones from the pituitary causes glands like the
pancreas to produce hormones (e.g. insulin).
• When hormone levels are too high, the hormones cause
the hypothalamus to stop sending its releasing
hormones. This is called negative feedback.