Download Chapter 2, section 2

Chapter 25, section 1
The Nervous System
Nervous System
• Two functions
1. Gathers and interprets ______
• Information
2. __________ to information gathered
• Responds
The Nervous System has two parts.
•
•
•
•
Central Nervous System (CNS)
brain and spinal cord
Peripheral System (PS)
all of the parts of the nervous system
except the ______ and _________
• Brain, Spinal cord
• PS uses specialized structures called
______
• nerves
Sensory Neurons
• Gather information about what’s
happening in and around your body
• Use ________
• Receptors
• ______ neurons send impulses from the
brain and spinal cord to other systems
• motor
Motor Neurons
• Send impulses from the ______ down the
spinal cord to parts of the body
• brain
• Make the body do stuff (action!)
Your brain has three parts:
• Cerebellum
• Cerebrum
• Medulla
Identify the brain part:
• Connects to your spinal cord
• Controls involuntary processes: body
temperature, heart rate, blood pressure
• medulla
Identify the brain part:
• Second-largest part
• Helps you maintain your balance
• cerebellum
Identify the brain part:
• Largest part
• Controls voluntary movements
• Allows you to sense touch, light, sound, odors,
taste, pain, heat, and cold.
• cerebrum
A _____________ is a nerve cell
that is able to transfer messages in
the form of fast-moving electrical
energy:
• neuron
Impulses are carried away from the
cell body by ____________
• Axons
• 7
Neurons receive information from
other cells through their _________
• Dendrites
• 1
The electrical messages that
neurons carry are called
_______________:
• impulses
A ________________ is a
collection of axons bundled
together with blood vessels and
connective tissue.
• nerve
Spinal cord
• Is protected by vertebrae
Homeostasis
• Keeping all body’s functions in balance
• Sympathetic and parasympathetic systems
working together to maintain homeostasis
Papillae
• Tiny bumps on your tongue
• Contain taste buds
Receptors
• Skin has different kinds of receptors
• There are receptors for
pressure
temperature
pain
vibration
Feedback mechanism
• Cycle of events in which information from
one step controls or affects a previous
step
EX: Cooling process of your body
Reacting to Light
Light passes
through
(from outside
to inside)
1. cornea
2. pupil
3. lens
Hearing a Sound
Sound travels
to your ear
1. Eardrum
2. Ear bones
3. cochlea
Olfactory Cells
• Upper part of the nasal cavity
• Sensory reactors for smell