Blood System
Blood Vessels
Blood Vessels
Three major types of blood vessels: arteries, capillaries,
and veins.
Arteries (arteri/o)
 large blood vessels that carry oxygen rich blood away
from the heart to the body, arterial blood is bright red
 Aorta is the main part of arterial system, begins in the
left ventricle
 Coronary arteries (coron/o) supplies
the heart with blood.
 Arterioles are thinner branches, carry
blood to capillaries
http://plus.maths.org/issue36/interview/artery.jpg
Blood Vessels Cont’d
Capillaries (capill/o)



Blood vessels that connect arteries and veins to each
other
Smallest vessels in the body
Blood flow is slower through capillaries; allows time for
exchange of oxygen, nutrients, and waste products
between surrounding cells and fluids
Veins (phleb/o, ven/o)



Responsible for carrying waste-filled blood back to heart
Veins have valves that allow for one-way blood flow
toward the heart
Venules are small veins that join to form larger veins
Pulse & Blood Pressure

Pulse – expansion and contraction of an artery
caused by the pressure of the blood moving through
the artery

Blood Pressure – measures the amount of
pressure applied against the walls of the vessels
Example – 124/72


Systolic Pressure – the upper number of
a blood pressure reading (124 / __ )
Diastolic Pressure – the lower number of
a blood pressure reading ( __ / 72)
http://www.stockphotography.com/img/medical/stock_photos/blood_pressure_cuff.jpg
Blood
The Blood (Hem/o or hemat/o)
 Blood is composed of 55% liquid plasma and 45%
formed elements. Formed elements are red blood
cells, white blood cells, and platelets.
Plasma
 Liquid part of blood; contains
nutrients, wastes and hormones
 91% water, 9% proteins
http://www.bloodservices.ca/centreapps/internet/uw_v502_mainengine.nsf/resources/Blood+Process/$file/Step6_150.jpg

Fibrinogen & prothrombin are clotting proteins to help
blood clot and control bleeding
Erythrocytes
Erythrocytes (erythr/o = red + -cyte = cell)
 Also called red blood cells (RBC’s)
 Contains hemoglobin (hem/o = blood + -globin =
protein) which is iron containing portion of
erythrocyte
 Hemoglobin transports oxygen from the lungs to the
tissues of the body
 Live about 120 days
Leukocytes
Leukocytes (leuk/o = white + -cyte = cell)
 Also called white blood cells (WBC’s)
 Protect body against infection

There are five types of leukocytes:


Neutrophils – majority of WBC’s, fight infection by
phagocytosis (engulfing & swallowing germs). Elevated
count indicates a bacterial infection (strep, staph, etc..)
Basophils – promote inflammatory response, elevated
basophil count may indicate an allergic condition (ex. allergic reaction, asthma, etc…)
Leukocytes Cont’d.

Types of Leukocytes cont’d.
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Eosinophils – formed in red bone marrow, increase in
response to allergic conditions (ex - allergic reaction,
asthma, etc…)
Lymphocytes – formed in red bone marrow, lymph nodes,
and spleen; protect body against disease
Monocytes – Also formed in red bone marrow, lymph nodes
and spleen. Help protect against disease, an elevated
count usually indicates a chronic (long-term) condition
http://www.lymphomation.org/images/leukocytes-normal.gif
Thrombocytes
Thrombocytes (thromb/o = clot + -cyte = cell)


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Also known as platelets
Smallest formed elements in the blood
When blood vessel is damaged,
platelets become sticky and clump
together to form a clot
http://sacs.vetmed.ufl.edu/histo/29b_sm.gif
Anatomy Sheet
Take out the “Anatomy of the Heart”
handout
 Fill in the blanks using the diagram on the
next slide
 Color the arteries blue
 Color the veins red
 THIS IS YOUR TICKET TO LEAVE!!!!!!

Blood Flow Through the Heart
A.
 The superior vena cava drains
deoxygenated blood from the head, neck,
and arms.
 The inferior vena cava drains deoxygenated
blood from the abdomen and the legs into
the right atrium.
 The coronary sinus drains deoxygenated
blood from the myocardium into the right
atrium.
Blood Flow Through the Heart
B.
C.
D.
From the right atrium, deoxygenated blood flows
through the tricuspid valve into the right ventricle.
From the right ventricle, deoxygenated blood
flows through the pulmonary semilunar valve into
the pulmonary trunk.
The pulmonary trunk branches to form the right
and left pulmonary arteries, which take
deoxygenated blood to the lungs for gas
exchange. Carbon dioxide is released from the
blood while oxygen is picked up by the blood.
Blood Flow Through the Heart
E.
F.
G.
Oxygenated blood returns through the right
and left pulmonary veins into the left
atrium.
From the left atrium, oxygenated blood
flows through the bicuspid (mitral) valve
into the left ventricle.
From the left ventricle, oxygenated blood
flows through the aortic semilunar valve
into the aorta.
Blood Flow Through the Heart
H.
I.
From the aorta, oxygenated blood flows
into the arteries, arterioles, capillaries,
venules, and veins, eventually reaching the
superior and inferior vena cava once again.
The body’s entire blood supply is circulated
every minute
Pattern of Circulation
RED =
O2 rich
BLUE =
O2 poor
Blood System Abbreviations
– pulse
 BP – blood pressure
 RBC – red blood cells
 WBC – white blood cells
P
Career Opportunities

Hematologist (hemat/o = blood + -ologist = specialist)

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specializes and treats disorders of the blood
Phlebotomist

Takes patient blood samples and prepares
them for testing in the lab
http://healthcare.maricopa.edu/images/PHLEB.jpg

Medical Laboratory Technologist (MT)


Works under the supervision of pathologist to study tissues, fluids,
and cells in the human body
Medical Laboratory Assistant

Prepares specimens for testing and helps clean and maintain
laboratory equipment.