Download Endocrine and Nervous Systems

Maintaining Homeostasis….
Together…
YAY HORMONES!
Primary Mission: Controlling the activity
of other body systems through chemicals.
• Secrete hormones
• Hormone
• A chemical made in one part of the body that affects another part of the
body.
• Circulate through blood or lymph
• Act only on specific organs or tissues
• Some important examples:
• Hypothalamus: regulates pituitary gland
• Pituitary gland: controls other endocrine
glands
• Pancreas: Produces Insulin and glucagon to
regulate glucose levels.
• Adrenal Glands: regulate metabolism and
adjust to stress in the body
• Pineal Gland: Regulate rhythmic cycles
(like heartbeat)
• Ovaries and Testes: Release reproductive
hormones
• Thyroid: regulates metabolism
• Thymus: Regulates immune responses
• Negative Feedback
• A process in which a
change in the environment
causes a response that
returns conditions to their
original status.
When you are hot or exercise strenuously, you lose water through
sweat. If you lose too much water, your pituitary gland releases a
hormone called ADH. Your blood carries the ADH to your kidneys,
where it signals the kidneys to slow the removal of water from the
blood. You also feel thirsty and take a drink of water. When the
water level in your body rise, the pituitary slows down and the
production of ADH. The kidneys increase the amount of water
removed from the blood, restoring your original water levels.
• How do you think your pituitary gland would respond if the
water level in your blood remained lower than normal? Why
might this happen?
The endocrine system is made up of glands that
A.
B.
C.
D.
Secrete enzymes that help to digest food.
Carry oxygen to all parts of the body.
Secrete hormones directly into the bloodstream.
Carry nerve impulses from one part of the body to another.
What is homeostasis?
A. The ability of an organism to maintain a relatively stable
internal environment
B. The production of a hormone by an endocrine gland that
works on another endocrine gland
C. A series of events that monitor how hormones work in the
body
D. A process in which a change in the environment causes a
response that returns conditions to their original status
Which is the correct sequence of steps in the negative feedback
system that adjusts your body temperature in a cold environment?
A. Hypothalamus– pituitary gland—thyroid gland– metabolism
increases
B. Pituitary gland– metabolism increases– hypothalamus–
thyroid gland
C. Thyroid gland—thyroxine—pituitary gland– metabolism
increases
D. Pituitary gland—thyroxine—thyroid gland– hypothalamus—
metabolism increases
Reacting to the World…
Controls and coordinates body
activities, including responses to
internal and external stimuli
• Stimulus
• Any condition in the environment that produces a reaction
• Light, temperature, movement, pressure, chemicals, and sound
• Response
• An organism’s reaction to a stimulus
• Endocrine Glands: chemical response (hormones)
• Nervous System: Electrochemical response
• Central Nervous
System
• Brain and Spinal
Cord
• Relays messages
• Processes
information
• Analyzes
information
• Receives and Sends
nerve impulses to
and from body
parts.
• Peripheral Nervous
System
• Nerves that are not
part of the brain or
spinal cord
• Somatic Nervous
system
• Regulates conscious
activities
• Autonomic Nervous
system
• Regulates
involuntary
activities
Sensory
• Carry impulses from the
sense organs to the spinal
cord and brain
Interneurons
• Carry
impulses
between
sensory and
motor
neurons
Motor
• Carry impulses from the
brain and spinal cord to the
muscles and glands.
Nerve Impulse
Neuron Communication
• Both the nervous and endocrine systems may respond to certain
stimuli. An example is the response of your body to cold
outdoor temperatures. Describe how both the nervous system
and the endocrine system might respond to a sudden drop in
temperature.
Which of the following BEST describes the role of the nervous
system?
A. Responds to all internal and external stimuli
B. Detects only stimuli from outside an organism
C. Responds only to stimuli occurring inside an organisms
D. Detects internal and external stimuli at the cellular level
Which of the following are cells of the nervous system?
A. Synapses
B. Potassium ions
C. Protein channels
D. neurons
Involuntary body activities are controlled by the
A. Somatic nervous system
B. Autonomic nervous system
C. Sensory receptors
D. interneurons
The role of motor neurons is to
A. Carry impulses from the sense organs to the spinal cord and
brain.
B. Carry impulses from the brain and spinal cord to muscles and
glands.
C. Carry hormones from an endocrine gland to its target organ.
D. Carry impulses between sensory neurons and endocrine
glands.