Chapter 19: Blood Flashcards
What type of tissue is blood
connective tissue consisting of cells surrounded by a liquid matrix (plasma)
Cellular components of blood
formed elements: red blood cells, white blood cells and platelets
plasma: water, proteins and other solutes
Name the different proteins found in blood plasma
- albumins (maintain bp)
- globulins (immunoglobulins –> antibodies)
- fibrinogen (helps w blood clotting)
Name the ‘other solutes’ in blood plasma
- electrolytes
- nutrients
- gases (O2)
- regulatory substances (molecules that control glands “hormones”)
- waste products (takes it to the kidney to be filtered)
Name the different white blood cells in blood
- neutrophils
- eosinophils
- lymphocytes
- monocytes
- basophils
RBC appearance and description
- biconcave shape
- larger surface area to allow O2 to go in and out quicker
- no nucleus
WBCs are very much like
typical cells and have a nucleus
3 main functions of blood
- blood transports oxygen, carbon dioxide, nutrients, hormones, heat and waste products
- blood regulates homeostasis of all bodily fluids, pH, body temperature, and water contents of all cells
- Blood protects against excessive loss by clotting, and uses white blood cells to protects against infection
Epithelium and cartilage do not have…
blood cells
Water in blood; description and function
- liquid portion of blood
- solvent and suspended medium. Absorbs, transports and releases heat
Plasma proteins in blood; description and function
- most produced by liver
- Responsible for colloid osmotic pressure (liquid pressure that results due to increased solutes)
- Contributes to blood viscosity
- Transport hormones, fatty acids, and calcium
- Regulate pH
Smallest and most numerous plasma proteins are…
Albumins
Albumins in blood plasma; description and function
- smallest and most numerous plasma proteins
- help maintain osmotic pressure, an important factor in the exchange of fluids across blood capillary walls
Globulins in blood plasma; description and function
- large proteins
- produce immunoglobulins which help attack viruses and bacteria
- Alpha and beta globulins transport iron, lipids and fat-soluble vitamins
Fibrinogen in blood plasma; description and function
- large protein
- plays essential role in blood clotting
- later turns into fibrin
Electrolytes in blood plasma; description and function (other solutes)
- inorganic salts; positively and negatively charged
- help maintain osmotic pressure and play essential roles in cell functions
Nutrients in blood plasma; description and function (other solutes)
- products of digestion such as amino acids, glucose, fatty acids, vitamin and minerals
- essential roles in cell functions, growth, and development
Gases in blood plasma; description and function (other solutes)
- O2, CO2, N2
- important in many cellular functions (O2)
- involved in regulation of blood pH (CO2)
- no known function (N2)
Waste products in blood plasma; description and function (other solutes)
- Urea, uric acid, creatine, creatinine, bilirubin, ammonia
- most are breakdown products of protein metabolism that are carried by the blood to organs of excretion
What type of blood cell loves for years while most other blood cells live for hours, days or weeks
Lymphocytes
What types of blood cells vary depending on invading pathogens and foreign antigens and what types of blood cells remain the same
- WBCs increase or decrease
- RBCs and platelets remain steady
What is the process of producing blood cells called
hemopoiesis
What is the name of the blood stem cells that differentiate into different types of blood cells
pluripotent stem cells
- can only turn into blood cells (also called multipotent stem cells)
Why is too many RBCs bad (polycythemia vera)
it makes the blood thick; having O2 is useful unless you can’t transport it quickly
What type of stem cell can turn into any type of cell
omnipotent stem cells
Pluripotent cells divide into 2 types
- Myeloid stem cell
- Lymphoid stem cell
Myeloid stem cells turn into
- RBCs
- Platelets
- Eosinophils
- Mast cells
- Neutrophils
- Basophils
- Monocytes
What type of precursor cells do platelets come from
- Megakaryoblast
platelets are fragments of megakaryocytes
Lymphoid stem cells turn into
- T lymphocyte
- B lymphocyte
- Natural killer (NK) cell
Lymphoid stem cells cannot turn into
RBCs
What protein do RBCs carry
hemoglobin which carries oxygen to all cells and carry some carbon dioxide to the lungs
Hemoglobin contains
an iron ion which allows each molecule to bind to 4 oxygen molecules
Oxygen poor blood
dark red
Oxygen rich blood
red
Red blood cells are involved in regulating blood flow and blood pressure via
the release of nitric oxide gas
Nitric oxide causes
vasodilation which improves blood flow and enhances oxygen delivery
Carbonic anyhydrase in RBCs catalyzes what?
the conversion of carbon dioxide and water into carbonic acid
What does carbonic acid do?
transports about 70% of carbon dioxide in the plasma
Carbonic anhydrase formula
H2O + CO2—> H + (HCO3)
How long do RBCs live for and how are they removed
- aprox 120 days
- dead cells are removed from the circulation by the spleen and the liver
What happens when RBCs die and get broken down
- hemoglobin breaks down into heme and globin
- globin turns into amino acids which are reused for protein synthesis
- Heme is broken down into iron (Fe) and Biliverdin
- Fe binds with transferrin into ferritin and goes into the liver and then to the bone for erythropoiesis
- Biliverdin turns into bilirubin and from the liver goes to the small and large intestines to be excreted from the body via feces
What is erythropoiesis
production of red blood cells
Erythropoietin?
a hormone released by the kidneys in response to hypoxia (lowered oxygen concentration) which stimulates differentiation of hematopoietic stem cells into erythrocytes
Reticulocytes
immature red blood cells that enter the circulation and mature in 1-2 days
White blood cells (leukocytes) contain
a nucleus but no hemoglobin
Lekucocytes are classified into two categories
Granular:
- containing vesicles that appear when the cells are stained
- neutrophils, eosinophils, basophils
Agranular
- contain no granules
- lymphocytes, monocytes
Eosinophils are granular leukocytes which stain…
red as in acidic
Basophils are granular leukocytes that stain…
blue as in alkaline
WBCs have the ability to emigrate…
during an invasion, many white blood cells are able to leave the blood stream and collect at sites of invasion
Elevation in WBCs normally indicates
infection or inflammation
Different types of WBCs help determine
different problems
Neutrophils (high and low count)
high count indicates:
- bacterial infection, burns, stress, inflammation
low count indicates:
- radiation exposure, drug toxicity, vit b12 deficiency, systemic lupus eruthematosus
Lymphocytes (high and low count)
high count indicates:
- viral infections, some leukemias, infectious mononucleosis
low count:
- prolonged illness, HIV infection, immunosupression, treatment with cortisol
Monocytes (high and low counts)
high count indicates:
- viral or fungal infections, tuberculosis, some leukemias, chronic diseases
low count indicates:
- bone marrow suppression, treatment with cortisol
Eosinophils (high and low count)
high count indicates:
- allergic reactions, parasitic infections, autoimmune diseases
low count indicates:
- drug toxicity, stress, acute allergic reactions
Basophils (high and low counts)
high count indicates:
- allergic reactions, leukemias, cancers, hypothyroidism
low count indicates:
- pregnancy, ovulation, stress, hypothyroidism
Megakaryocytes in red bone marrow splinter into
2000-3000 fragments to create platelets that contain many vesicles but no nucleus
Platelets are used to
clot blood
How long do platelets survive for
- 5-9 days
- the liver hormone thrombopoietin stimulates formation of platelets from megakaryocytes
Neutrophils function
phagocytosis, destruction of bacteria
Eosinophils function
combat effects of histamine in allergic reactions
- destroy parasitic worms
Basophils function
liberate heparin, histamine and serotonin in allergic reactions that intensify overall inflammatory response
Lymphocytes (T cells, B cells + natural killer cells) function
- mediate immune responses
- B cells develop into plasma cells which develop antibodies
- T cells attack invading viruses, cancer cells and transplanted tissue cells
Monocytes function
phagocytosis (macrophages)
When are bone marrow transplants used
to replace cancerous red bone marrow with normal red bone marrow
Where is the donor’s marrow usually collected from
iliac crest of the hip bone
Other ways bone marrow can be helped
stem cells collected and frozen from an umbilical cord after birth may also be used
What is hemostasis
the sequence if events that stop bleeding
3 steps in hemostasis
- vascular spasm
- platelet plug formation
- blood clotting (coagulation)
Vascular spasm
- smooth muscle contraction (automatic)
- smooth muscle constricts blood vessels
- allows less blood to be lost
Platelet plug formation step 1
- platelet adhesion: activation and aggregation of platelets
- platelets know to form a plug at a specific site because collagen fibers and endothelium activate platelet formation
Platelet plug formation step 2
- platelet release reaction:
- ADP, serotonin, and thromboxane released
- when substances are released it activates more platelets to come to site
- they change shape to contact and stick to each other
Platelet plug formation step 3:
- platelet aggregation: if the cut is small the platelets are enough, if it is a big cut then fibrin is needed to strengthen
Blood clot formation
complex chemical reaction that results in the production of protein fibrin which secures platelet plug (like glue)
Blood clotting can be activated in one of 2 ways
- Extrinsic pathway
- Intrinsic pathway
Once the clot is formed…
it retracts (tightens) and pulls the edges of the damaged vessels together
Vitamin K is used for
the synthesis of 4 clotting factors
What are small unwanted clots dissolved by
plasmin (fibrinolysin) which breaks down/digests fibrin threads
Blood types and antibodies
- blood plasma usually contains antibodies (agglutinins) that react with A or B antigens
An individual will not have agglutinins against
their own blood type
Blood type A
- has A antigen
- has B antibodies
- can receive from A and O
- cannot receive from B, AB
Blood type B
- has B antigen
- has A antibodies
- can receive from B, O
- cannot receive from A, AB
Blood type AB
- has AB antigens
- has neither A or B antibodies
- can receive from A, B, AB, O
Blood type O
- has no antigens
- has A, B antibodies
- can receive from O
- cannot receive from A, AB, B
Blood typing and cross matching
- done to determine a persons blood type
- a drop of blood is mixed with antiserum
- if the blood agglutinates it is positive for that antigen
Hemolytic disease of the newborn
- when anti Rh antibodies cross the placenta and attack some of the fetus’ red blood cells causing agglutination and hemolysis
- normally occurs after first pregnancy
- A + B antibodies are too big to cross the placenta however, Rh antibodies can cross
Sickle cell anemia
- genetic anemia where oxygen-carrying capacity of the blood is reduced
What type of hemoglobin do individuals with sickle cell anemia contain
- they contain hemoglobin s which causes red blood cells to bend into a sickle shape when it fives up oxygen to the interstitial fluid
Anemia
a condition where oxygen carrying abilities are decreased
