Transcript BLOOD

BLOOD
Erythrocytes: Red blood cells which carry
oxygen on hemoglobin
Leukocytes: White blood cells which protect
against disease
Thrombocytes: Platelets which are
responsible for blood coagulation
Erythrocytes
Thrombocytes
Leukocytes
Hematocrit = percent of blood
cells in whole blood. The
normal hematocrit is 45%
cells and 55% liquid (plasma).
A 152 lb. person has 5-6 liters
or 10.5-12.5 pints of blood
The pH of blood is 7.35-7.45
Hemopoiesis = the formation &
development of blood cells. It
takes place in the red
marrow of spongy bone.
By age 20, blood cell
production only occurs in the
bone marrow of large bones:
humerus, femur, cranium,
ribs, sternum, scapula,
clavicles, vertebrae.
Blood cells are made in the
bone marrow.
Erythrocytes = RBC’s have nuclei only
in early development, & lack nuclei
when mature. This makes more room
for hemoglobin. Life span of RBC’s is
120 days.
The shape of the cells allows them to
adapt to the job of transporting gas.
Normal amounts of RBC
Males = 5,450,000mm3
Females = 4,750,000mm3
Erythropoietin- a hormone (produced by
kidney & liver) that controls the rate of
RBC formation. Also known as Epo, it
is given to cancer patients, since
chemotherapy causes anemia. Epo is
also illegally used by athletes to
increase bloods oxygen carrying
capacity. This procedure is known as
blood doping.
Red blood cell in arteriole
Erythropoietin
The cell membrane of RBC’s is highly
elastic so cells can change shape
when passing through tiny
capillaries.
Sickle cell anemia results in
irregularly shaped RBC’s which
lose elasticity and get stuck in
capillaries.
Hemoglobin- is the oxygen-carrying
red pigment in RBC’s. Each cell is
1/3 hemoglobin. It’s made of
protein (globin) & iron (heme).
The # of circulating RBC’s determines
the blood’s oxygen-carrying ability.
The production of RBC’s is influenced
by vitamin B12 and folic acid.
Normal & Sickle shaped
RBC
Leukocytes- white blood cells, are twice
the size of RBC. They protect against
disease by producing antibodies, killing
parasites by phagocytosis, or killing our
own cells when they are infected by a
parasite or are cancerous.
There are 5-9000 WBC/mm3. They have
a life span of 12 hours to years.
Leukocytes
All are nucleated. Their size and shape
vary.
There are five types of leukocytes
Neutrophils
Basophils
Eosinophils
monocytes
Lymphocytes
Neutrophils and monocytes exhibit
ameboid movement and are phagocytic
(surround and engulf parasites).
WBC activity increases during infection
Macrophage
phagocytosis of bacillus
bacteria
CBC = complete blood count. It is a
test to determine the percentage of
WBC’s and RBC’s in blood. This is
used for diagnosis. Too few RBC’s
is anemia. Too many WBC’s =
infection. If cells are immature, =
leukemia.
Thrombocytes = fragments of cells
called platelets. Life span is 10
days. They are made in red bone
marrow, and the quantity is
250,000-500,000/mm3.
They are small (half the size of RBC),
granular, with no nucleus.
They initiate a chain reaction which
results in blood clotting.
Plasma = the liquid portion of blood
and consists of water, amino acids,
protein, carbohydrates, lipids,
vitamins, hormones, electrolytes,
wastes.
Blood components can be
separated by centrifugation
Functions of plasma are
1. Transport nutrients, gases, &
vitamins.
2. Help regulate the fluid &
electrolyte balance.
3. Maintain pH.
Physiology of blood
1. Helps control water level in tissues
2. Maintains acid-base balance
3. Maintains body temperature
4. Protects against disease
5. Transports gases
Blood Types depent on the type of antigen
present on the cell membrane.
Types = A (has A antigen) B (has B antigen)
AB (has both A and B antigens) and
O (with neither A or B antigen).
Blood types were discovered by Karl Landsteiner
Type O is recessive
Type A & B are dominant
In the USA, Type O = 45% can receive Type O
Type A = 41% can receive A, O
Type B = 10% can receive B, O
Type AB = 4% can receive A, B, O,
Blood water levels
regulated by increasing
or decreasing urine
volume
= universal donor
AB = universal receiver
Rh factor: 85% of individuals have this
antigen. They are referred to as Rh+.
Those who do not have the Rh
antigen are referred to as Rh-.
Hemolysis- breakdown of RBC’s and
release of hemoglobin into the
plasma.
Example Dad is Rh+, mom is Rh- &
baby inherited Rh+ from dad. If it is a
1st pregnancy, no problem. If a 2nd
pregnancy, mom’s antibodies can
cross the placenta and cause
hemolysis, resulting in
erythroblastosis fetalis.
The released hemoglobin can damage
baby organs, cause severe anemia,
and if the baby is born alive, it will
need many transfusions.
Medical Terminology for Blood
Anemia- Deficiency in red blood cell number or low
hemoglobin content. Both result in a reduced O2 supply.
Signs of anemia 1. pale 2. weak
3. little energy
4. labored breathing 5. rapid heart rate
6. intolerance to cold
Thrombosis = blood clot
Embolus = clot that has dislodged from its place of origin
Heparin =anticoagulant used after surgery to reduce the
risk of clotting
Hemorrhage-(external or internal)
= excessive bleeding
Loss of ½ liter of blood (10%)
= no effect
Loss of 35% = serious
Loss of 50% = fatal
Cerebral Hemorrhage
Intestinal Hemorrhage
Top = intestine with hemorrhage
Bottom = normal intestine
DISORDERS
Hypoxia
1. causes prolonged oxygen
deficiency and results in
cyanosis. Skin turns blue
due to high
deoxyhemoglobin.
2. Exposure to low
temperature causes
superficial blood vessels to
constrict, resulting in a
decrease in blood flow. This
allows more oxygen to be
removed from the blood in
proximal areas, making less
oxygen available in distal
areas.
Blood Cells not carrying O2
Deep
water
blackout
is due to
cerebral
hypoxia
DISORDERS of THE BLOOD
Newborn Jaundice. Immature
liver cells excrete bilirubin into
bile. Accumulation of bilirubin
causes yellow skin. Exposure
to fluorescent lights used to
break down bilirubin
Sickle Cell Disease caused by a
single DNA base change which
results in crystalization of
hemoglobin. Instead of being
round, the RBCs become
sickle-shaped in a low oxygen
environment. Causes severe
pain and hypoxia due to
blocked circulation.
NEW THERAPY: bone marrow
transplant can cure sickle cell
anemia, but there is a 15% risk
of death
Newborn with Jaundice
DISORDERS of THE BLOOD
Leukemia
Symptoms colds, fever, chills, bruises,
bone pain, fatigue, normal blood
clotting disrupted
1. Myeloid leukemia too many white blood
cells. Cells are immature and can not
fight infection. The cells crowd out
the RBCs and platelets.
2. Lymphoid leukemia involves
lymphocytes produced in the lymph
nodes.
3. Acute leukemia appears suddenly.
Rapid death (within a few months).
4. Chronic leukemia begins slowly and
may not be detected for months. Life
expectancy is 3 years if not treated. If
treated, 50-80% go into remission.
Child with leukemia
receiving
chemotherapy
Hemophilia Uncontrolled bleeding,
due to an abnormal in one of the
clotting factors.
Hemophilia A is the most common
Symptoms hemorrhage
nose bleed
hematoma
blood in urine
Caused by a mutation on the X
Chromosome. Therefore, it is
classified as a sex-linked
inherited illness.
The mother usually does not have
the illness, but passes on the
gene. Therefore, she is called a
carrier.
The disease is usually found in
males, since they only have a
single X Chromosome.
Females have two X Chromosomes
and would require both alleles to
be mutated for them to have
hemophilia.
Bruises continue to bleed