INTRODUCTION TO BODY
SYSTEMS
WHAT DO THE BODY
SYSTEMS DO?
Humans and other organisms need to get
energy.
Body systems, also called organ systems,
help organisms to do all of these things.
They also coordinate all the functions of
a body.
There are eleven body systems –
1. The muscular system: allows
movement of body parts. Consist of
skeletal, smooth and cardiac muscles.
There are approximately 640 skeletal
muscles within a typical human.
BODY SYSTEMS
2. Skeletal system – is made up
bones, ligaments, and cartilage.
It supports the body and
protects important organs. It
also makes blood cells. The
human skeleton has 206 bones.
BODY SYSTEMS
3. Respiratory system – gathers
oxygen from the environment and
gets rid of carbon dioxide form the
body. The primary organs of the
respiratory system are lungs, which
carry out this exchange of gases as
we breathe.
BODY SYSTEMS
4. Cardiovascular
system – moves
blood through the
body. The heart is
the pump for this
system. Includes the
veins, arteries,
capillaries, heart,
and blood.
5. Male reproductive
system – produces sperm
and delivers it to the female
reproductive system.
Female reproductive
system – produces eggs and
nourishes a developing
fetus.
BODY SYSTEMS
6. Lymphatic system –
returns leaked fluid back to
the blood. The primary
function of the lymphatic
system is to
transport lymph, a fluid
containing infectionfighting white blood cells,
throughout the body.
BODY SYSTEMS
The spleen plays multiple
supporting roles in the body.
It acts as a filter for blood as
part of the immune system.
Old red blood cells are
recycled in the spleen,
and platelets and white
blood cells are stored there.
BODY SYSTEMS
7. Endocrine system –
makes chemical
messages. They also
influence growth and
development. Is made
up of glands that
produce and secrete
hormones, chemical
substances produced
in the body that
regulate the activity
of cells or organs.
BODY SYSTEMS
8. Integumentary
system – is the
protective covering
of the body. It
includes the skin,
hair, and nails. The
skin acts as a
barrier that
protects the body
from infection.
BODY SYSTEM
9. Excretory system –
gets rid of the body’s
wastes. The urinary
system removes
wastes from blood.
The skin, lungs, and
digestive system also
remove wastes from
the body.
BODY SYSTEM
10. Digestive system – breaks down
food into nutrients that can be used by
the body. The stomach breaks down
food into tiny pieces. Digestion begins
in the mouth with chewing and ends in
the small intestine.
The gallbladder then stores the extra bile
the liver makes. It releases bile when
you eat a meal with fats that need to be
digested.
BODY SYSTEM
11. Nervous system – collects
information and responds to it by
sending electrical messages. The
brain is the center of the nervous
system. The nervous system of
vertebrates (including humans) is
divided into the central nervous
system (CNS) and the peripheral
nervous system (PNS). The
(CNS) is the major division, and
consists of the brain and
the spinal cord.
WHAT ARE THE BASIC NEEDS OF ALL CELLS?
Cells need to get enough oxygen to carry out life
processes and to have their wastes taken away.
They also need an energy/food supply.
HOW ARE STRUCTURES AND FUNCTION LINKED?
oThe shapes and sizes of cells are related to their function.
oFor example, sperm cells have long tails that are used to move.
oNerve cells are long and thin to send messages long distances.
oSkin is made up of different cells in many layer. The epidermis is
the outer layer of skin. The dermis is the second layer of skin, and
contains glands, hair follicles, and blood vessels.
WHAT IS HOMEOSTASIS?
oCells need certain conditions to work properly.
oThey need food and oxygen and to have their wastes taken away.
oIf body conditions were to change too much, cells would not be
able to do their jobs.
oHomeostasis – is the maintenance of a constant internal
environment when outside conditions change.
WHAT CAN GO WRONG WITH HOMEOSTASIS?
oIf one body system do not work properly, other body systems can be
affected.
oFor example, body cells that do not get enough or nutrients cannot work
properly.
oThe presence of toxins or pathogens also can disrupt homeostasis.
oToxins can prevent cell from carrying out life processes and pathogens can
break down cells.
COMPLETE THE FOLLOWING TABLE:
Alcoholism is a disease that disrupts homeostasis. Below are three body systems that
are affected by alcohol. The effects on the nervous system are filled in. In the space
provided, make a claim about what might happen when the function of the two
remaining systems is affected.
Body systems affected
What are the effects?
Nervous system
Disrupts proper functioning of the brain. The brain
cannot respond properly to internal or external
messages.
Digestive system
The liver and other organs of the digestive system can
be harmed by alcohol, which will affect the ability of
the digestive system to digest food and remove toxins.
Reproductive system
Affecting the reproductive system could harm the ability
to produce healthy sex cells, or in the case of a woman,
develop and nourish a healthy fetus or baby.