Chapter 4

Communication and Control

Vocabulary

Central NervousSystem (CNS)

BrainSpinal Cord

PeripheralNervous System

(PNS)

All parts of the Nervous System

Neuron

A specialized cell to receive and conduct electrical impulses

Nerve

A collection of fibers which impulses through travel of the body

Brain

Main control center

Reflex

An involuntary and immediatemovement in response to a stimulus

Retina

A layer of light -sensitive cells

Cochlea

A fluid-filled organof the inner ear

EndocrineSystem

Controls bodyfunctions

Gland

A group of cells that make up special chemicals for your body

Hormone

A chemical messenger madein one cell that causes a change in another cell

Section1: The Nervous System

Central NervousSystem (CNS)

BrainSpinal Cord

The Nervous System has two parts:

1) Central (CNS)

2) Peripheral (PNS)

The CNS acts as the control center for your body.

The PNS carries information to and from the CNS.

1) What does the CNS consist of?___________________

Brain andSpinal cord

Arms andLegs

2) What system acts as the control for your body?__________________CNS

PNS

PeripheralNervous System

All parts of the Nervous System

The PNS connects all parts of your body to the CNS.

The PNS uses special nerves to carrythe information to the CNS.

1) ____________ uses special nerves to carry information.PNS

CNS

2) __________ connects to all parts of the body.

CNS

PNS

3) What is the special nerve called?____________

neuron axon

These special nerves are called neurons.

NerveA collection of fibers which impulses through travel of the body

Nerves are everywhere in your body.

Nerves have axons that are both sensory neurons and motor neurons.

The axon in the nerve transmits informationfrom the spinal cord to the muscle fibers.

1) Nerves have _____________ that are both sensory and motor neurons.axons

muscleshttp://www.youtube.com/watch?v=sjyI4CmBOA0

Click on the blue button to watch a video on the nervous system.

Brain Main control center

Many processes that the Brain controls happens automatically.

a) You cannot stop food from digesting.

b) This is called an involuntary process.

c) Some actions are voluntary.

d) When you move your arm, this is a voluntary process.

1) What action is an involuntary process?________________digesting food

eating food

2) What action is a voluntary action?_________________

move your arm

digest food

http://www.youtube.com/watch?v=Z48xmSxo8Co

Click on the blue button to watch a video on the brain.

Section 2: Responding to the Environment

ReflexAn involuntary and immediatemovement in response to a stimulus

When you step on something sharp,pain receptors in your foot sendimpulses to your spinal cord.

This involuntary action is calleda Reflex.

1) Reflex is an ______________________action.

voluntary

involuntary

http://www.youtube.com/watch?v=HZRVmjWZVXM

Click on the blue buttons to watch a short video on reflexes.http://www.youtube.com/watch?v=dU8kehupjEY

Retina A layer of light -sensitive cells

Your eyes are sensory organs.

Your eyes detect light which enables your brain to form visual images.

The retina is packed with photoreceptors.

a) rods

b) cones

Rods are sensitive to dim light.

Cones are sensitive to bright light.

1) The retina has two photoreceptors__________________________.rods & cones

square & circle

Cochlea A fluid-filled organof the inner ear

Hearing

A coiled tube that is found in the inner ear.

Ears are specialized organs for hearing.

Neurons in the cochlea change the waves into electrical impulses.

http://www.youtube.com/watch?v=E9GYaSngkVE

Click on the blue button to watch a video on inner ear hearing.

1) What special kind of tube is found in the inner ear?__________________

square coiled

2) A fluid-filled organ in the inner ear is called?___________________

CochleaRetina

EndocrineSystem

Controls bodyfunctions

The Endocrine System controls body functions by using chemicals that are made by the endocrine glands.

a. These glands secrete hormones and regulate growth, development and homeostasis.

b. regulates fluid balance.

http://www.youtube.com/watch?v=gH8dGK7s6lY

Click here to watch a video on the endocrine system.

1) What system regulates growth and development?____________________

endocrinenervous

2) The Endocrine system controls body functions by using _________________?

chemicalsnervous

GlandA group of cells that make up special chemicals for your body

Some Endocrine Glands are:

pituitary: stimulates skeletal growth

regulates the amount of water in your blood

thyroid: controls growth hormones for normal body growth

controls your metabolism

http://www.youtube.com/watch?v=wh6e_5bCfnw

Click the blue button to watch a video on glands.

1) What gland controls growth hormones?_______________

thyroidpituitary

2) What gland stimulates skeletal growth?_____________________

thyroid pituitary

HormoneA chemical messenger madein one cell that causes a change in another cell

A substance that is made on one cell or tissue and that causes a change in another cell or tissue in a different part of the body.

Hormone medications can be used to treat endocrine disorders.

1) What medications can be used to treat disorders?__________________

hormonetissue

2) Hormones are __________________messengers.

chemicalcell

http://www.youtube.com/watch?v=ZGJNhPJN_UU

http://www.youtube.com/watch?v=ZGJNhPJN_UU

Click on the blue button to watch a video on target cell interactions.

http://www.youtube.com/watch?v=I8uXewS9dJU

Click on the blue button to watch a video on cells and tissues.