What is Blood? - Lighthouse Christian Academy
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Transcript What is Blood? - Lighthouse Christian Academy
UNIT J: CIRCULATORY SYSTEM
(Ch. 13, pp. 226-234 & Ch. 14, pp. 250-251, 254 & Ch. 22, pp. 430-431)
J1. Describe and differentiate among the five types of
blood vessels. (p. 226-227)
J3. Demonstrate safe and correct dissection
techniques (Not covered in text)
J4. Distinguish between pulmonary and systemic
circulation. (p. 234-235)
J5. Identify and describe differences in structure and
circulation between fetal and adult systems. (Ch. 22
p. 430-431)
J2. Identify and give functions for each of the following
(p. 234- 235):
a)
Subclavian arteries and veins
b) Jugular veins
c) Carotid veins
d) Mesenteric arteries
e) Anterior and posterior vena cava
f)
Pulmonary veins and arteries
g) Hepatic vein
h) Hepatic portal vein
i)
Renal arteries and veins
j)
Iliac arteries and veins
k) Coronary arteries and veins
l)
Aorta
J6. Demonstrate a knowledge of the path of a blood
cell from the aorta through the body and back to
the left ventricle. (p. 234-235)
J7.
List the major components of plasma. (p. 237)
J8.
Identify and give functions for lymph, capillaries,
veins, and nodes. (Ch. 14 p. 250-251)
J9.
Describe the shape, function, and origin of red
blood cells, white blood cells, and platelets. (p.
237-240)
J10. Demonstrate the correct use of the compound
microscope. (Not covered in text)
J11. Explain the roles of antigens and antibodies.
(Ch. 14 p. 254)
J12. Describe capillary-tissue fluid exchange. (p. 241)
Note: J3 and J10 are not examinable on the Provincial Biology 12 exam.
•Acclimatize
•Afferent arteriole
•Agglutination
•Anaemia
•Anterior vena cava
•Antibody
•Antigen
•Aorta
•Aortic arch
•Arteriole
•Artery
•Atrioventricular (AV) valve
•Blood clot
•Blood pressure
•Brachial artery
•Capillary
•Capillary fluid exchange
•Carbaminohemoglobin
•Carbonic anhydrase
•Carotid arteries
•Chemoreceptor
•Contrict
•coronary
•Diastole
•Dilate
•Ductus arteriosus (arterial duct)
•Ductus venosus (venous duct)
•Edema
•Efferent arteriole
•Electrocardiogram (EKG)
•Erythrocyte
•Fetus
•Fibrin
•Fibrinogen
•Foramen ovale
•Hemoglobin
•Hepatic portal vein
•Hepatic vein
•Histamine
•Hypertonic
•Hypotonic
•Iliac artery/vein
•Jugular vein
•Leucocyte
•Lymph
•Lymph capillary
•Lymph duct
•Lymph node
•Lymphatic duct
•Lymphatic system
•Mesenteric artery
•Valve
•Oxyhemoglobin
•Venule
•Pacemaker
•Villi
•Phagocytic
•White blood cell
•Platelet
•Posterior vena cava
•Pressure receptor
•Prothrombin
•Pulmonary artery/vein
•Pulmonary circulation
•Pulse
•Red blood cell
•Renal artery/vein
•Rhesus (Rh) factor
•RhoGAM
•Precapillary sphincter muscle
•Subclavian artery/vein
•Systemic circulation
•Systole
•Thrombin
•Thrombocyte
•Thromboplastin
•Thymus gland
•Umbilical cord
•Umbilical artery/vein
What is Blood?
• Blood is more than just a red liquid that
leaks onto your best white shirt when you
cut yourself!
•How much blood does your heart pump in a day?
7,000 litres
•How long do red blood cells live? 4 months
•How long does blood last outside your body?
5 days
•In a tiny drop of blood, there are 250 million RBC’s,
375,000 WBC’s, & 16 million platelets!!!
• Your body has about 5.6 liters of blood, which
circulates through the body 3 times every minute.
• During an average lifetime, the heart will
pump enough blood to fill over 100 fullsized swimming pools.
Blood is 55% Plasma (Liquid)
The plasma portion of blood is:
• 91% Water
Maintains blood volume
Transports molecules
• 7% Proteins (ie: clotting
proteins, albumin,
immunoglobulins…)
• 2 % Salts, gases (O2, CO2),
nutrients, wastes,
hormones, vitamins, etc…
Blood is 45% Formed Elements (Solids)
The solid portion of blood is:
Red Blood Cells
Erythrocytes/corpuscles
White Blood Cells
Leukocytes
Platelets
Thrombocytes
HOW ARE RBC’s MADE?
•
When the liver and kidneys detect low levels of oxygen in
the body, they release chemicals (REF and GLOBULINS)
that stimulate the red bone marrow to increase production
of RBC’s.
•
It takes several weeks to build up the rate of erythrocyte
production and this is why it takes a while to become
acclimatized when you:
a) Visit or move to a higher elevation
b) Hemorrage after an accident
c) Have sickle cell anaemia
Red Blood Cells (RBC’s)
• No nuclei
• Transport CO2 and O2 and H+
(acts like a buffer)
• Bioconcave discs: look like
donuts without complete holes!
• Live for ~ 120 days (4 months)
• Dark purple to bright red
• Contain hemoglobin molecules,
carbonic anhydrase, and antigens
• There are ~800 million oxygen
molecules in each RBC
• Made in the red bone marrow
Erythrocytes
Transports oxygen as oxyhemoglobin (bright red)
Hb + O2
------------------------------- HbO2
Hb attaches to oxygen when
it’s cool, high pH, and low
pressure (ie: at the lungs)!
Transports carbon dioxide as carboxyhemoglobin
Hb + CO2
-------------------------------
HbCO2
Transports hydrogen ions as reduced hemoglobin (thus
acting as a buffer)
Hb + H+
-------------------------------
HHb
Note: fetal hemoglobin has a
greater affinity for oxygen than
maternal hemoglobin!
White Blood Cells
(Leukocytes)
• They make histamines, antibodies
and hunter killer cells
• Fight Infection: the antibodies
attach to foreign invaders & the
hunter killer cells destroy them.
• WBC’s can squeeze out of blood vessels to attack invaders.
They have
strangely shaped
nuclei.
They are also
made in the red
bone marrow
Platelets
(Thrombocytes)
• 150,000-300,000 / mm3 blood
• They are just fragments of
cells with no nuclei
• We produce ~ 200
billion/day
• Made in bone marrow
Platelets
• Aid in blood clotting
• Recognize micro tears in blood vessels
& bind together to form a blood clot
Formation of a Blood Clot
Step 1
- A Vessel and Platelets become DAMAGED some way.
Step 2
- Platelets release a protein called THROMBOPLASTIN.
Step 3
- Thromboplastin changes PROTHROMBIN (a blood protein
produced by the liver) into THROMBIN (requires Calcium)
Step 4
- Thrombin changes FIBRINOGEN (another blood protein
produced by the liver) into FIBRIN (insoluble)
Antigens/Antibodies & Blood Type
Antigens and Antibodies
have different but related
functions!
Antigen:
an identification protein on a RBC
• It is a glycoprotein on the RBC membrane
• There are two kinds of antigens on human
RBC's: A and/or B
• Therefore, there are 4 possible blood types:
Antigen A Type A blood
Antigen B Type B blood
Antigens A & B Type AB blood
No Antigens Type O blood
Antibody: a protein designed to combat any foreign protein
• Made by the WBC in the body
• Will bind to foreign proteins with foreign antigens
• This causes AGGLUTINATION = clumping
• WBC’s will then destroy the agglutinated cells
Antigen + Antibody
(Foreign)
(Yours)
+
Y
(Agglutinization)
=
YYYYY
Y
YY YY
Our blood has antibodies that are opposite to
the antigens we have on our RBC’s.
WHY?
So we don’t attack our own blood!
This is what it ‘looks’ like
Type A has B antibodies
Type B has A antibodies
Type O has A and B antibodies
Type AB has No antibodies
• Therefore blood transfusions are tricky:
introducing foreign antigens can lead to…
DEATH
Note: Antibodies are REMOVED from donated
blood – they cannot cause agglutination
Blood donor
Blood Type
A
B
AB
O
A
B
AB
O
yes
clumps
clumps
yes
clumps
yes
clumps
yes
yes
clumps
yes
clumps
yes
clumps
yes
yes
The Rh factor is another antigen that may be present
on the RBC. The presence of this antigen plays a role
in childbirth.
•If you are Rh+ you have the antigen and don’t have the
‘D’ antibodies. (85% of Caucasians are Rh+)
Rh +
NO ANTIBODIES
•If you are Rh – you don’t have the antigen. You don’t
normally have the ‘D’ antibodies, but can make them if you
are exposed to Rh antigens.
Rh -
HAS ANTIBODIES, BUT
ONLY WHEN EXPOSED
TO Rh+ BLOOD
•If Rh antigens are mixed with Rh antibodies,
agglutination occurs.
Donor
Rh +
Rh -
Recipient
Anti-Rh
Antibodies
in Recipient's
Blood
Rh -
Will Produce
anti-Rh
Antibodies
Rh +
Will Not
Produce
anti-Rh
Antibodies
Rh Blood
Rh +
Blood
WHY ELSE IS THIS IMPORTANT?
•If an Rh- mother has an Rh+ baby,
complications can occur with a second
pregnancy.
•Normally, the mother / fetal blood does not
mix or cross the placenta.
•However, at birth, there is usually some
mixing, and the mother will begin to produce
Rh antibodies in response to the Rh
antigens on the baby's Rh+ RBC's.
•There is no danger for either the mother or
the first baby.
BUT…If the mother becomes pregnant with
another Rh+ baby, the mother’s antibodies
(made during the birth of the 1st child) are small,
and can cross the placenta.
These antibodies will agglutinate the baby's blood.
This will cause the baby to
die / be still born
(Erythroblastosis).
How can this be prevented?
When the first Rh+ baby is born, doctors can destroy the
Rh+ blood cells in the mother's plasma before the
mother has time to make the Rh antibodies.
An injection of Rh immune globulin injection (RhoGAM)
does this.
CIRCULATION
Blood and Blood Vessels
Blood Vessels – The 5 Main Types
1. Arteries
2. Arterioles
3. Capillaries
4. Venules
5. Veins
http://www.youtube.com/watch?v=PgI80Ue-AMo
• The aorta, the largest artery in
the body, is almost the diameter
of a garden hose.
• The aorta in a blue whale is so
big, you could swim down it!!!
• Capillaries, on the other hand, are so small
that it takes ten of them to equal the thickness
of a human hair.
• One pound of excess fat adds approximately 200
miles of extra capillaries. This increases BP!
•If you stretched your veins out, and hooked
them all together, they would go around the
world 2 times!!
1) Arteries
Function
• Transport blood AWAY
from the heart
Structure
• Thick, elastic walls
Location
• Usually deep, along bones
• This protects them from injury
and temperature loss.
Notes
• Walls can expand
• Arteries have very high Blood Pressure
• Expansion is the “pulse” we feel
Arteries of the Human Body
2) Arterioles
Function
• Control blood flow to capillaries
Structure
• Smaller in diameter than arteries, thinner walls
• Have pre-capillary sphincters
Location
• Leading towards all capillaries
Notes
• Blood Pressure > Osmotic Pressure
• Regulate blood pressure with
pre-capillary sphincter muscles:
can dilate or constrict to increase
Afferent = incoming
Efferent = outgoing
or decrease blood flow to a
particular capillary bed.
3) Capillaries
Function
• Connect arteries to veins
• Site of “capillary-fluid exchange”
Structure
• Very thin walls (1 cell thick)
Location
• Everywhere; within a few cells of each other
O2
CO2
Capillary-Fluid Exchange on Arteriole Side
A. Arteriole Side
• Blood pressure @ arteriole side = 40 mmHg
• Osmotic pressure = 25 mmHg
• Net Blood pressure (15mmHg) forces water out of the
blood into the interstitial fluid
• Water carries with it the O2 and nutrients
• Because there is more O2 and nutrients in interstitial
fluid, it diffuses into body cells
• The large things (ie: RBC, WBC, platelets, blood proteins)
stay in the capillary because they are too big to leave.
• Because most of the water has left, the blood becomes very
hyperosmotic (concentrated)
• The venule side of the capillary is therefore under great
osmotic pressure to draw water back into the blood.
VIDEO: http://www.youtube.com/watch?v=B658Yn3INYc
Capillary-Fluid Exchange on Venule Side
B. Venule Side
• Osmotic pressure @ venule side = 25 mmHg
• Blood pressure = 10 mmHg
• Blood very concentrated (has little water)
• Net osmotic pressure (15mmHg) forces water back into the
blood
• Water carries with it CO2 and metabolic wastes (urea)
• These are carried to the kidneys and other excretory organs
to be removed.
4) Venules
Function
• Drain blood from capillaries
Structure
• Thinner walls than veins
Location
• Often near the surface
Notes
• Join to form veins
• Osmotic Pressure > Blood Pressure
• The end result is no change in blood volume (ie:
no volume is lost in the exchange)
5) Veins
Function
• Transport blood TOWARDS the heart
Structure
•
Inelastic walls, contain one-way valves
Location
• Often near to surface
Notes
• Blood pressure & velocity is much lower than in arteries
• Valves prevent blood from flowing backwards
• Surrounded by skeletal muscle, “squeezes” blood along
Veins of the Human Body
How Does It All Fit Together?
• Arteries:
– Carry blood away from the
heart
– Elastic
• Capillaries:
– Very thin tubes
– Connect arteries to veins
– Can close down or open up to
regulate blood flow
– GAS EXCHANGE
• Veins:
– Bring blood towards the heart
– Have valves to stop blood
from moving backwards
The Circulatory System is organized into two parts:
Systemic Circulation: system of blood vessels that
delivers oxygenated blood to body systems.
Pulmonary Circulation: system of blood vessels that
delivers deoxygenated blood to the lungs to be replenished
with oxygen
What is the big deal?
The systemic arteries carry oxygenated blood.
The pulmonary arteries carry deoxygenated blood.
PULMONARY
ARTERY
VENA
CAVA
PULMONARY
VEIN
AORTA
Pulmonary and Systemic Circulation
SYSTEMIC CIRCULATION
Pulmonary and Systemic Circulation
SYSTEMIC CIRCULATION
Pulmonary and Systemic Circulation
PULMONARY CIRCULATION
Pulmonary and Systemic Circulation
PULMONARY CIRCULATION
B. The Major Blood Vessels of the Body
Cranial vein
VENA CAVA
Cranial artery
AORTA
Brachial artery
1. Aorta
• Biggest Artery
• Carries O2 rich blood from left ventricle to
body systems
• Loops over top of heart, creating
the AORTIC ARCH
• Goes down inside of backbone
= DORSAL AORTA
• Smaller arteries branch off to
‘feed’ the body cells
2. Coronary Arteries/Veins
•Very first branch off the aortic arch
•Blood vessels that “FEED” the heart muscle
Why can’t the heart just get
its oxygen and nutrients
from the blood that passes
through it?
3. Carotid Arteries
• Branch off the aortic arch to
take the blood to the head
• Supply blood to brain = highly
specialized:
CHEMORECEPTORS
detect oxygen content
PRESSURE RECEPTORS
detect changes in blood
pressure
• Reasonably close to the
surface, pulse can be found
in neck
4. Jugular Veins
• Take blood out of head region to the anterior
vena cava
• These veins DO NOT contain
any valves!
•
Blood flows down them
because of gravity only
Try standing on your head for a while!
5. Subclavian Arteries/Veins
• Arteries branch off of aorta and travel under the
clavicle
• Branch to feed chest wall/arms (via brachial arteries)
• Note For Later: Lymphatic Ducts join circulatory
system right before the subclavian veins meet up
with the anterior vena cava
6. Mesenteric Arteries
• Branch off from the dorsal aorta
• Go to the intestines
• Branch into capillaries of the intestinal villi
• Pick up the newly digested nutrients (glucose,
amino acids and nucleotides)
Mesentary
Mesenteric
Arteries
7. Hepatic Portal Vein
• Hepatic = Liver; Portal = capillary bed on either end
• This vein transports blood rich in nutrients
directly from the intestines to the liver
Remember the liver functions??
• Significant functions for
the circulatory system:
regulation of blood [glucose]
Destroys old RBC’s
detoxification of blood
HEPATIC
PORTAL
VEIN
8. Hepatic Veins
• Carries the blood from liver
to posterior vena cava
9. Renal Arteries/Veins
• Renal arteries branch off
dorsal aorta and bring blood
to kidneys
• Renal veins take blood from
kidneys to posterior vena
cava
10. Iliac Arteries/Veins
• Dorsal aorta branches into two iliac
arteries in the pelvic area
• One iliac artery goes down each leg
• Femoral artery branches off iliac artery
to large quadricep muscle
• Iliac veins return blood to
posterior vena cava
11. Pulmonary Arteries/Veins
• deO2 blood collected from the body is pumped into
the pulmonary artery from the right ventricle
• Pulmonary artery brings deO2 blood to lungs
• Blood picks up O2 in the alveoli of lungs
• Pulmonary vein takes high O2 blood back to
left atrium of heart
Pulmonary
Artery
Pulmonary
Vein
Part D. The Lymphatic System
“A system of thinwalled vessels with
valves that drain
fluids from bodies
tissue spaces”
Functions of the Lymphatic System
1. Take up excessive tissue fluids
2. Transport fatty acids and
glycerol (from intestines to
subclavian vein)
3. Fight infection (lymphocytes)
4. Trap and remove cellular debris
Structures of the Lymphatic System
1. Lymph Ducts and Capillaries
•
Drain and collect excess fluids from tissues
•
Take fluids to nodes to be cleaned
•
Cleansed lymph travels through lymph ducts to the
subclavian vein where they are dumped into the
anterior vena cava
2. Lymph Nodes
• Remove debris from lymph =
‘cleanse’ lymph
• Contain Phagocytic Lymphocytes
• White Blood Cells make
antibodies and attack invaders
3. Lacteals
• absorb/transport fatty
acids & glycerol in the villi
of the small intestine.
4. Other Lymphoid Organs
• Tonsils, Appendix, Spleen, and Thymus gland
Please see attached
“SCHEMATIC DIAGRAM”
worksheet NOW!
•A fetus does not use its lungs.
•The fetus receives its O2 blood from the placenta, not its
lungs.
•To do this, there are four features in the fetus not
present in the adult.
•This is an opening
between the Left and
Right atria
•It is covered by a flap
that acts as a valve
•It allows the blood to
bypass the lungs
•It reroutes most of the
blood from the right
atrium into the left
atrium.
•This is a small arterial
connection, like a shunt.
•Between the pulmonary
artery and the aorta.
•It further allows blood to
bypass the lungs.
•The Umbilical Cord has three
blood vessels traveling through it.
•The largest one is the
umbilical vein, which transports
blood with oxygen and nutrients
into the fetus.
•The other two are the umbilical
arteries, which branch off of the
iliac arteries in the fetus, and
take “spent” (wastes and CO2)
blood back into the mother via
the placenta.
•This blood vessel connects the
umbilical vein to the vena cava.
•The O2 blood from the umbilical
vein mixes with deO2 blood in the
vena cava.
•The ductus venosus bypasses the liver and this blood
is sent directly to the heart.
•Blood will go to the liver eventually, but not until it has
reached the hepatic portal vein.
•This is why the fetus is so susceptible to toxins in
blood.
The First Breath: the lungs are filled with air instead of
fluid and higher oxygen levels in the blood and alveoli
results in an increase in pulmonary blood flow.
Anatomical Changes:
The placenta is removed from circulation.
The foramen ovale, ductus venosus, and
ductus arteriosus close.