Transcript Slide 1 - mscsclass

Unit 3 Lecture 3: Peripheral nervous system
(PNS) and the Endocrine System
A. Peripheral Nervous System (PNS)
• What is the PNS?
– The nerves that run throughout your body connecting your sensory
organs (skin, eyes, ears, tongue, nose) to your brain and spine (CNS)
• 2 parts: somatic and autonomic
– Somatic nervous system: controls voluntary muscle movement and
reflex responses (balance, blinking, knee jerk)
– Autonomic: controls involuntary internal organ actions
Quick think and write:
•What are 3 examples of somatic actions?
•What are 3 examples of involuntary actions you are doing right now?
Somatic: turning page as you read, choosing to run or jump or talk
Autonomic: breathing, heart rate, digestion, salivation
Autonomic Nervous System
• 2 parts: sympathetic and parasympathetic
– Sympathetic: Drives flight or fight response during
stressful/strenuous events
• Speeds up heart, directs blood flow to muscles that
need most oxygen, suspends digestion
– Parasympathetic: relaxation
PNS (shown in blue) and
CNS (shown in red)
neurons/nerves
Incoming signals
•Sensory: PNS nerves carry
signals from body to CNS
spinal cord and brain
•Receptors: receive
information (sound, light,
heat, pressure, flavor, smell)
from environment (auditory
receptors, olfactory, visual,
kinesthetic, taste buds)
PNS (shown in blue) and
CNS (shown in red)
neurons/nerves
•Motor: carry outgoing
signals from the CNS to
the muscles, skin, and
glands of body
Internal CNS messages
carried by interneurons
between spine and brain
Quick-draw challenge
Draw a multi-panel comic strip (simple stick figures are fine) that shows the path of
the incoming message as it comes from the environment, gets to your body, travels
through your body, and your sends out a response message in the following
situation:
Sample: A child touches a hot stove.
Your turn: Mosquito lands on your arm.
Be sure to label the following on your strip and provide a short caption for each image!!
• Sensory: carry signals from body to spinal cord and brain (Central Nervous
System or CNS)
• Motor: carry signals from the CNS to the muscles, skin, and glands of body
• Receptors: receive information (sound, light, heat, pressure, flavor, smell)
from environment (auditory receptors, olfactory, visual, kinesthetic, taste
buds)
• Inter: neurons found in CNS (spinal cord and brain)
B. Endocrine System
• Function? Sends hormone
chemical messages to body’s
organs to control metabolism,
growth, sexual development
• In females: ovulation,
menstruation, and lactation
• In males: sperm production,
deepening of voice, growth of
sex organs
• More examples:
– Thyroid gland produces thyroxin
• Too little = lazy
• Too much = overactive
– Adrenal glands release
adrenalin when person
frightened or angry