Blood Powerpoint Ch 6

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Transcript Blood Powerpoint Ch 6

Blood’s functions
Chapter 6
• Maintains homeostasis in the body
• Picks up oxygen in the lungs and transports it
to the cells.
• Picks up nutrients from the digestive system
to transport to cells.
• About 75 mL of blood is pumped through the
heart each heart beat. X 70 per minute =
5,250 mL or 5.25 Liters per minute.
Blood’s functions
• Picks up waste carbon dioxide from the cells to exhale out the lungs and
mouth and nose.
• Excess nitrogen is transported to the kidneys where it is filtered out into the
• Distributes heat in the blood to cells.
• Transports regulating hormones and proteins throughout the body.
Blood’s functions
• Defend the body against pathogens blood loss.
• Makes antibodies to disable pathogens.
Blood’s functions
• Antibodies flag bad invaders for T cells to destroy by phagocytosis.
Blood’s functions
• Platelets and Proteins clot the
blood to prevent loss of blood
and death.
• Prothrombin and Fibrinogen
activate when there is a cut and
start working to clot the blood.
• Globulins
• Albumins
Blood components
• Formed elements are red blood cells
(erythrocytes), white blood cells
(leukocytes), and platelets.
• Red blood cells are smaller than White
Blood Cells.
• Millions of RBCs and 1000s of WBCs in 1 mm3
of blood.
• Plasma is the liquid part of blood.
• Contains dissolved salts and proteins, which
create osmotic pressure, which attracts water.
• Blood buffers keep the blood pH around 7.4.
Platelets (thrombocytes)
• Megakaryocytes
fragment in the red
bone marrow.
• 200 billion every day.
• 150,000 to 300,000 per
mm3 in blood.
• Platelets help clot blood with prothrombin & fibrinogen from the liver.
• Vitamin K is essential for making prothrombin.
• 12 or more clotting factor proteins and Calcium ions make clots.
• Prothrombin activator is released at cut or bruise
• Calcium helps convert prothrombin to thrombin which cuts two short
amino acid chains from two fibrinogen threads.
• They join end to end in ropes making a framework clot.
• Plasmin enzyme destroys fibrin so tissues grow.
• Yellow fluid called serum escapes. It has same parts of plasma except for
fibrinogen and prothrombin.
How blood cells are formed
• Stem cells in red bone
marrow are pluripotent: they
are parent cells that give rise
to different blood cells.
• Stem cell research is figuring
out what switches need to be
present to form different blood
Blood components
• Plasma proteins like fibrinogen, globulins, and albumins are produced
in the liver. One type is produced by white blood cells.
• Fibrinogin helps clot the blood
• Most plasma proteins are albumins, they combine with and help transport
other organic molecules.
• Globulins are of 3 types: alpha, beta, and gamma.
• Alpha and Beta help transport hormones, cholesterol, and iron.
• Gamma globulins are antibodies produced by white blood cells called lymphocytes.
• Plasma proteins are too large to pass through capillary walls so they
stay in the blood, so water absorbs back into the capillaries and veins.
Review and Practice activity
Red Blood cells (erythrocytes)
• 6-8 micrometers wide,
biconcave, without a nucleus
and most organelles.
• Anaerobically make ATP
• Transports Oxygen and Carbon
• Protein called hemoglobin that
has four highly folded chains
and a central iron group that
grabs oxygen, changes shape,
and lets it go in the tissues.
Carbon dioxide
• 7% of carbon dioxide is dissolved in plasma.
• Higher percentage would turn our blood to carbonated soda
• 25% of carbon dioxide is bound to hemoglobin
• 68% of carbon dioxide joins with water to form Carbonic Acid
(H2CO3-) in plasma sped up by an enzyme carbonic anhydrase, then
forms Hydrogen ions and Bicarbonate ion (HCO3-). The acid H+ joins
with the hemoglobin protein to keep blood pH constant.
• At the lungs the process reverses.
Red blood cells
• Because they lack organelles and a nucleus they
die in 120 days, and are phagocytized by white
blood cells in the liver and spleen.
• About 2 million per second.
• Hemoglobin is broken down into amino acids in
the liver and kidneys
• Most Iron is returned to bone marrow, but some
is lost.
• Caused by build up of heme in the liver (yellowing of skin and eyes)
• Heme is chemically broken from red/purple to blue to green to
Homeostasis and regulation of oxygen
• Too little oxygen releases a kidney and liver hormone called
• Erythropoietin stimulates red bone marrow stem cells to make more
red blood cells.
Blood cell disorders
• Anemia- run down feeling
• Lack of Iron, so lack of hemoglobin.
• Vitamin B12, (pernicious anemia)
• Lack of stem cell producing DNA so less RBCs.
• B vitamin folic acid (folic acid anemia)
• Common in pregnant women
• Rupturing of red blood cells
Sickle-cell anemia
• Hereditary disease caused by the change of one amino acid that turns
the red blood cell sickle shaped, and doesn’t transport enough
• RBCs die in 90 days
White Blood Cells
• Fight infection and clean up old cells
• Largest blood cells, have a nucleus, lack hemoglobin, Translucent
unless stained.
• Made in red bone marrow from stem cells
• Colony stimulating factor protein controls production of each type of white
blood cell
• Normal healthy person produces wbcs in hours.
• WBCs squeeze through capillary wall pores to get into tissues and
• Granular
• Phagocytize pathogens and old cells
• Don’t stain with acids or bases. (Neutral)
• 50-70% of all WBCs.
• Polymorphonuclear leukocyte
• Granular
• Bilobed nucleus
• Digest large pathogens like parasite worms
• Reduce inflammation or swelling
• Found in allergic reactions
• Stained with a red acid stain
• Granular
• Promote blood flow to injured tissues
• Inflammation by releasing histamine which dilates blood vessels but
constricts air tubes to the lungs (asthma)
• Stain with bases to a dark blue color
• Agranular
• 25-35% of all WBCs
• Specific immunity to a particular pathogen or toxin
• B cells- produce antibodies which are proteins that fit on a particular
pathogen and mark them for destruction
• T cells- destroy pathogens
• AIDS attacks T cells.
T cell
• Agranular
• Largest WBC
• Live in tissues, become larger
• In skin they are called dendritic cells. They destroy old cells and
dissolve cellular debris.
• They stimulate other white blood cells to defend the body.
• Severe Immunodeficiency Disease (SCID)
• 100 children are born yearly where WBC Stem cells lack enzyme adenosine
deaminase, so T & B cells don’t develop.
• Leukemia- uncontrolled cell growth of WBCs. Different types based on
WBC affected.
• Epstein-Barr Virus infectious mononucleosis. Herpes family. Virus
remains dormant in throat and lymph glands. Passed by kissing.
• - low platelet production in bone marrow
• Or increased breakdown of platelets
• Bruise, rash, nosebleeds, mouth bleeding, gastrointestinal bleeding, brain
• Clots form an embolism that can cause death due to inactivity.
Hemophilia• X chromosome carries a clotting factor gene.
Abnormal copy of Factor 8 causes non-stop
• Girls have two copies, boys have one copy of the gene.
• Tsar of Russia (Anastasia’s brother had this disease).
Blood types video
• Antibody types
• The + and – refer to the presence or absence of Rhesus clotting factor.
• A+, A• B+, B• AB+, AB• O+, O-
Blood types lab