Download What is the nervous system?

Miss Sauer Chapter 2: Cell Structure and Function
Lesson 2: How are cells specialized? (Pages A52-A63)
Circulatory System: organ system that carries oxygen to the body and
removes carbon dioxide and other wastes.
Hormones: the chemical message that travels through the blood and
carries special information for certain cells.
Endocrine System: controls the body’s metabolic activity & secretes
different types of hormones into the blood stream.
Nervous System: controls movements and other organ systems.
What is the nervous system?
The nervous system is the highway along which your brain sends and
receives information about what is happening in the body and around it.
This highway is made up of billions of nerve cells, or neurons (say newrons) which join together to make nerves.
 A nerve is a fibre that sends impulses through the body.
 These fibres are covered by fatty substance called
myelin (say my-e-lin). Myelin helps the messages go fast
through the neurons.
 Nerve cells work by a mixture of chemical and electrical
action.
The two main parts of the nervous system are the central nervous system
and the peripheral (say per-if-er-al) nervous system.
Organs: two or more types of tissue that work together to perform a
function.
Musculoskeletal System: the system of muscles and tendons and
ligaments and bones and joints and associated tissues that move the
body and maintain its form.
Respiratory system - the system for taking in oxygen and giving off
carbon dioxide; in terrestrial animals this is accomplished by breathing.
Your respiratory system is made up of the organs in your body
that help you to breathe. Remember, that Respiration =
Breathing. The goal of breathing is to deliver oxygen to the body
and to take away carbon dioxide.
Parts of the respiratory system
Lungs
The lungs are the main organs of the
respiratory system. In the lungs oxygen is
taken into the body and carbon dioxide is
breathed out. The red blood cells are
responsible for picking up the oxygen in the
lungs and carrying the oxygen to all the
body cells that need it. The red blood cells
drop off the oxygen to the body cells, then
pick up the carbon dioxide which is a waste
gas product produced by our cells. The red
blood cells transport the carbon dioxide back
to the lungs and we breathe it out when we
exhale.
Contents
Trachea
The trachea (TRAY-kee-uh} is sometimes called the windpipe. The trachea
filters the air we breathe and branches into the bronchi.
Contents
Bronchi
The bronchi (BRAHN-ky) are two air tubes that branch off of the trachea
and carry air directly into the lungs.
Contents
Diaphragm
Breathing starts with a dome-shaped muscle at the bottom of the lungs
called the diaphragm (DY-uh-fram). When you breathe in, the diaphragm
contracts. When it contracts it flattens out and pulls downward. This
movement enlarges the space that the lungs are in. This larger space pulls air
into the lungs. When you breathe out, the diaphragm expands reducing the
amount of space for the lungs and forcing air out. The diaphragm is the main
muscle used in breathing.
Digestive system
Digestive System: breaks down food.
Tissue: group of cells with a common structure and function.
Lesson 3: How does disease affect cells? (Pages A64-A73)
Immune System: an organ system that fights disease and foreign
agents.
Infectious Disease: a disease caused by organisms or viruses.
Non-infectious Disease: a disease caused by malfunction of an organ
system.
***Know examples of both infectious & non-infectious diseases.***
DISSECTIONS:
Dissection: Earthworm
Functions:
Crop - stores food
Gizzard – grinds food
Anus – removes wastes
Dissection: Frog
Frogs tongues are attached at the front of their mouths.
Functions:
Heart - pumps blood and nutrients throughout the body
Lungs – allows for breathing