Download W1D4 - The Circulatory System

Warm-up
 Patice takes a bite out of her cheeseburger
from McDonalds. Write out all of the digestive
system organs the cheeseburger goes
through.
 Mouth Esophagus Stomach
Duodenum/ Small Intestine  Large
Intestine Rectum/Anus
 What does ATP stand for?
 Adenosine Triphosphate
Mr. Mah
Living Environment
Lecture 4
THE CIRCULATORY
SYSTEM
AIM:
How does the
circulatory system
help us to main
homeostasis?
Review: Homeostasis
 A set of stable conditions that are maintained
inside an organism (staying the same).
 It is necessary for life. An organism that
cannot maintain homeostasis may get sick or
die
 Digestive System helps maintain
Homeostasis by making sure the body has
enough food and nutrients for survival
What is the circulatory system?
 The circulatory system carries blood and dissolved
substances to and from different places in the body.
 The Heart has the job of pumping these things
around the body.
 The Heart pumps blood and substances around the
body in tubes called blood vessels.
 The Heart and blood vessels together make up the
Circulatory System.
Parts of the Circulatory System
 Heart
 Blood
 Arteries
 Veins
 Capillaries
The Heart
 Has 4 chambers; 2 atria (Left Atrium,
Right Atrium) and 2 ventricles (Left
Ventricle, Right Ventricle).
 Blood flows through the heart in one
direction.
 Valves control the blood flow.
 A bunch of nerve cells at the top of the
right atrium, called the pacemaker,
controls heart rate (how fast the heart
beats).
Blood Flow Through the Heart
 Remember, there are 4 chambers of the heart
(Left Atrium, Right Atrium, Left Ventricle,
Right Ventricle).
 Blood that comes back from your body first
enters the Right Atrium, into the Right
Ventricle, where it gets pumped to the Lungs
to get oxygen.
Blood Flow Through the Heart
Follow the Blue
Arrows. Blood
first enters into
the Right
Atrium, then
goes into the
Right Ventricle.
It gets pumped
to the lungs
through the
Pulmonary
Artery.
Respiratory System Interaction
 Blood from the Right Ventricle travels
through the Pulmonary Arteries into the
lungs for oxygen
 Then comes back to the heart into the Left
Atrium through the Pulmonary Veins.
 The blood goes into the Left Ventricle,
where it gets pumped to the rest of the
body through the Aorta
Blood Flow Through the Heart
Follow the Red
Arrows. Blood
first enters into
the Left
Atrium, then
goes into the
Left Ventricle.
It exits the heart
from the Aorta
Blood Flow Through the Body
Blood
 Complex mixture
of cells, water,
and various
proteins and
sugars.
 Fifty-five percent
is plasma (liquid).
 Forty-five
percent is solid.
4 Main Parts of Blood
red blood cell
platelets
white blood cell
plasma
What’s In Blood?
digested food
red blood cells
white blood cells
oxygen
waste (urea)
platelets
carbon dioxide
plasma
hormones
Arteries
 Carry blood AWAY from the heart.
 Large, thick-walled, muscular, and elastic
Veins
 Carry blood back to the heart
 Blood returns to the heart through
the veins.
 Thin blood vessels with valves which
bring the blood back to the heart.
 Has valves which act to stop the
blood from going in the wrong
direction.
Capillaries
 CONNECT arteries and veins, it is here
that substances are loaded and unloaded
into the blood.
 Dense network of tiny blood vessels that
make sure the oxygen and nutrients in our
blood reach all the cells in our bodies.
 The thin capillary walls (ONE CELL
THICK!) allow nutrients and gases to
diffuse (move) easily between blood cells
and surrounding tissue.
The CAPILLARY
A collection of capillaries is known
as a capillary bed.
artery
vein
body cell
capillarie
s
Arteries  Capillaries
 Veins
Follow A Red Blood Cell
Through the Body
 Start in the Right Atrium:
 Right Atrium  Right Ventricle 
Pulmonary Arteries  Lungs 
Pulmonary Veins  Left Atrium  Left
Ventricle  Aorta  Arteries  Capillaries
 Veins  Right Atrium
Are you alive?
 Check your PULSE!
 Place two fingers (index and middle) on your
wrist (thumb side) right under your thumb
 Press firmly against the bone until you feel a
pulse
 Count the number of beats for 30 seconds,
then multiply that number by 2