Transcript Circulatory System - Hrsbstaff.ednet.ns.ca

Circulatory System
Biology 11
Video

PBS: Mysterious Human Heart
Open vs. Closed

Open Circulatory System: Blood is not
contained in vessels, bathes tissues and
organs directly.
Example: Arthropods and most mollusks

Closed Circulatory System: Blood is
contained in vessels.
Example: Vertebrates and earthworms
Human Circulatory System
3 main parts:

Heart

Blood

Vessels
Function of Circulatory System

The circulatory system transports oxygen and
carbon dioxide, nutrients, wastes and
hormones throughout the body.
Blood

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Normally, 7-8% of human body weight is from
blood.
This essential fluid carries out the critical functions
of transporting oxygen and nutrients to our cells and
getting rid of carbon dioxide and other waste
products.
In addition, it plays a vital role in our immune system
and in maintaining a relatively constant body
temperature.
Blood Composition
Plasma
Platelets
White blood
cells
Red blood
cell
Whole Blood
Sample
Sample Placed
in Centrifuge
Blood Sample
That Has Been
Centrifuged
Components of Blood
4 Main components:
 Red blood cells
 White blood cells
 Platelets
 Plasma
Red Blood Cells


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Red blood cells, or erythrocytes, are relatively large
microscopic cells without nuclei.
They transport oxygen from the lungs to all of the
living tissues of the body and carry away carbon
dioxide.
Hemoglobin is the gas transporting protein
molecule that makes up 95% of a red cell.
*FYI: Each red cell has about 270,000,000 iron-rich
hemoglobin molecules.
White Blood Cells


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White blood cells, or leukocytes, exist in variable
numbers and types but make up a very small part of
blood's volume-normally only about 1%.
White cells are a major part of the immune system.
They also have the function of getting rid of invaders
(such as viruses and bacteria), old unneeded blood
cells as well as foreign matter such as dust and
asbestos.
Platelets

Platelets, or thrombocytes, are cell
fragments that clot blood at the site of
wounds.
Plasma

Plasma is the relatively clear liquid protein
and salt solution which carries the red cells,
white cells, and platelets.

About 95% of plasma consists of water.
Blood Type

Q: What causes a bruised bone?

A: Two types…

Sub-periosteal Hematoma:
Collection of blood located underneath the protective membranous
layer on bones called the periosteum. Tends to occur as a result of
direct force trauma against a bone, usually in a leg.

Inter-osseus:
Occurs from compressive forces being applied to a bone that cause
internal injury to the bone marrow. Professional athletes, such as
football and basketball players as well as runners, are at higher risk
for these injuries.
Anatomy of the Human Heart

PBS: Nova interactive
The Heart
Superior Vena Cava:
Large vein that
brings oxygen-poor
blood from the
upper part of the
body to the right
atrium
Right Atrium
The Heart
Left Atrium
Pulmonary
Veins:
Bring oxygen-rich
blood from each
of the lungs to the
left atrium
The Heart
Pulmonary Valve:
Prevents blood
from flowing back
into the right
ventricle after it
has entered the
pulmonary artery.
Right Atrium
Pulmonary
Arteries
The Heart
Right Atrium
Tricuspid Valve:
Prevents blood
from flowing back
into the right
atrium after it has
entered the right
ventricle
The Heart
Right Atrium
Inferior Vena Cava:
Vein that brings
oxygen-poor blood
from the lower part of
the body to the right
atrium.
The Heart
Left Atrium
Mitral Valve:
Prevents blood
from flowing back
into the left atrium
after it has entered
the left ventricle
Left Ventricle
The Heart
Aorta
Left Atrium
Aortic Valve:
Prevents blood
from flowing back
into the left
ventricle after it
has entered the
aorta
Left Ventricle
The Heart
Pulmonary Arteries:
Bring oxygenpoor blood to
the right or left
lung
The Heart
Aorta:
Brings oxygen-rich
blood from the left
ventricle to the
body
Septum

The septum divides the right side of the heart
from the left.

It prevents the mixing of oxygen-poor and
oxygen-rich blood.
Blood Flow
Pulmonary
Circulation:
Circulates blood
between the heart
and the lungs.
In the lungs, carbon
dioxide leaves the
blood and oxygen is
absorbed. The
oxygen-rich blood
returns to the heart.
Blood Flow
Systemic Circulation:
Circulates blood
between the heart
and the rest of the
body.
After returning from
the lungs, the
oxygen-rich blood is
pumped to the rest
of the body.
3 Types of Blood Vessels

Arteries: Carry blood away from the heart

Veins: Return blood back to the heart

Capillaries: Tiny blood vessels that allow for
gas exchange and diffusion.

Q: How / why does nitroglycerine work?

A: It dilates blood vessels, therefore
decreasing blood pressure during an angina
attack (chest pain).
Blood flow…
The “rules”

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Left side of heart  oxygen rich blood
Right side of heart  oxygen poor blood
Atria receive blood
Ventricles pump blood
Arteries flow away from heart
Veins flow towards heart
Pulmonary = lungs
Trace a RBC…

Right atrium right ventricle 
pulmonary arteries  arterioles
 capillary bed (in lung) 
venule  pulmonary veins 
left atrium  left ventricle 
aorta  arterioles  capillary
bed (body / organs)  venule
 inferior or superior vena
cava  right atrium…
Exam Prep

Study Skills
Textbook Review
Read Pages 242-258
 Questions 1-2 page 243
 Questions 1-8 page 246
 Questions 1-4 page 253
 Question 1-2 page 258
What is this???
Crane video

PBS: Nova Science Now
Growing Hearts?