leukocytes, platelets, and hemostasis Flashcards
week 2
— are the only formed element that is a complete cell with organelles and a nucleus
leukocytes
how many leukocytes are in microliters blood?
4,800 to 10,800
leukocytes play an essential role in the body’s — response
immune
what is positive chemotaxis?
it’s when white blood cells are attracted to the site of infection or injury by a chemical signal released by damaged cells.
what is diapedesis?
how white blood cells “squeeze” through blood vessel walls to reach where they’re needed in the body.
what is the term for an elevated number of leukocytes?
leukocytosis
what is the term for a decreased number of leukocytes
leukopenia
what are the five types of leukocytes?
neutrophils, lymphocytes, monocytes, eosinophils, basophils
which leukocytes are granulocytes?
neutrophils, eosinophils, and basophils
which leukocytes are agranulocytes?
lymphocytes, monocytes
what is the order of abundance of leukocytes?
neutrophils, lymphocytes, monocytes, eosinophils, basophils (Never Let Monkeys Eat Bananas)
what is a specific function of neutrophils?
fight bacteria and inflammation.
what is a specific function of eosinophils?
defend against parasites and allergies.
what is a specific function of basophils?
trigger inflammation and help control immune response.
what is a specific function of lymphocytes? (T-cells and B-cells)
T-Cells: Fight virus-infected and tumor cells.
B Lymphocytes (B-Cells): give rise to antibody-producing plasma cells
what is a specific function of monocytes?
large cells that turn into macrophages, which eat pathogens and help activate lymphocytes for immune responses.
chemical messengers called — or —trigger the creation of leukocytes
interleukins; colony-stimulating factors (CSFs)
like erythrocytes, leukocytes come from —
hematopoietic stem cells
hemocytoblasts are quickly differentiated into — and — stem cells
lymphoid; myeloid
Myeloid stem cells give rise to —, —, —, and all the —
erythrocytes, platelets, monocytes, and granulocytes
— arise from the myeloid line of stem cells
myeloblasts
— collect lysosomes
promyelocytes
— collect granules
myelocytes
In Band Cells, the nuclei form a —
curved arc
In mature granulocytes, nuclei are —
segmented
— are derived from the myeloid line
monocytes
— are derived from the lymphoid line
lymphocytes
T Lymphocyte Precursors give rise to immature T-Cells which mature in the —
thymus
B Lymphocyte Precursors give rise to immature B-Cells which mature in the —
bone marrow
what is leukemia?
the overproduction of abnormal leukocytes
how is leukemia caused?
when a single blood cell undergoes uncontrolled division, producing too many leukocytes that aren’t fully functional
excessive leukocytes impair normal function of —
red bone marrow
what are the four types of leukemia?
acute, chronic, myeloid, and lymphocytic
what is infectious mononucleosis?
highly contagious viral disease typically seen in young adults
infectious mononucleosis is caused by the —
Epstein-Barr Virus
what are some symptoms of infectious mononucleosis?
fatigue, body aches, chronic sore throat, and low-grade fever
how long does recovery take for infectious mononucleosis?
4 to 6 weeks
how does chemotherapy work?
by using drugs to kill rapidly dividing cancer cells, but it can also affect healthy cells that divide quickly.
platelets are fragments of very large cells, called —
megakaryocytes
the granules contained in platelets play important roles in —
blood-clotting
what would happen without platelets?
blood loss from an injured or damaged blood vessel would continue indefinitely
platelets age — and degenerate within — days
quickly; 10
where do platelets come from?
A hormone called thrombopoietin
Each microliter of blood contains — platelets
150,000 to 400,000
what is hemostasis?
a fast, localized reaction to stop blood loss from a damaged or injured blood vessel
what are the three steps of hemostasis?
- Vascular Spasm
- Platelet Plug Formation
- Coagulation
following successful hemostasis, the blood clot will retract and dissolve, what happens when the blood successfully clots?
the clot is replaced by fibrous tissue, which more permanently prevents blood loss
what happens in the first step of (vascular spasm) hemostasis?
blood vessels constrict immediately after injury to reduce blood flow and minimize bleeding.
what happens in the second step of (platelet plug formation) hemostasis?
platelets stick to the damaged area of the blood vessel and each other, forming a temporary plug to stop bleeding.
what happens in the third step of (coagulation) hemostasis?
a series of chemical reactions occur that convert fibrinogen into fibrin, forming a stable blood clot to seal the wound.
what three things can vascular spasms be triggered by?
- injury to blood vessel walls
- chemicals from damaged cells and platelets
- pain signals from nearby nerves
normally, platelets don’t stick to each other or to the blood vessel walls because of the constant release of — and —
prostacyclin; nitric oxide
a plasma protein, called —, stabilizes bound platelets
von Willebrand factor
what is Adenosine Diphosphate (ADP)?
a strong substance that causes platelets to stick together and form clumps.
what is Serotonin and thromboxane A?
chemicals that help strengthen vascular spasms and promote platelet clumping.
Once activated, clotting factors trigger a 3-phase cascade that results in coagulation and vessel repair through the enzyme — and the molecule —.
thrombin; fibrin
what happens during phase 1 of coagulation?
factor X gets activated, either through the damage to tissue (extrinsic) or blood vessel (intrinsic), and preparing for the next step in making a clot.
what happens during phase 2 of coagulation?
prothrombin is changed into thrombin, which will help form the blood clot.
what happens during phase 3 of coagulation?
when fibrin forms the “net” that traps blood cells and makes the clot strong and stable.
platelet-derived growth factor (PDGF) stimulates — and — to form a connective tissue patch
smooth muscle cells; fibroblasts
vascular endothelial growth factor stimulates — to multiply and restore the endothelial lining
endothelial cells
what is Fibrinolysis?
the process of removing unneeded clots when vessel healing has occurred
what is Plasmin?
an enzyme that helps break down fibrin and removes blood clots.
the presence of a clot, triggers endothelial cells to secrete —
tissue plasminogen activator (tPA)
what is tPA (tissue plasminogen activator)?
a protein that helps break down blood clots by converting plasminogen into plasmin, the enzyme that dissolves clots
what is tPA (tissue plasminogen activator) often used for?
a treatment for strokes or heart attacks caused by clots.
what are Anticoagulants?
substances that inhibit blood clotting
what is a natural anticoagulant found in endothelial cells?
heparin
heparin inhibits —
thrombin
how does Nitric oxide help prevent blood clots?
by stopping platelets from sticking to blood vessel walls.
what mineral is essential to forming a blood clot?
calcium
thromboembolic disorders cause —
undesired clot formation
bleeding Disorders prevent —
desired clot formation
what’s the difference between a thrombus and an embolus?
A thrombus is a clot that forms in a blood vessel, while an embolus is a clot that breaks loose and moves through the bloodstream.
example of a thrombus?
myocardial Infarction
two examples of an embolus?
pulmonary emboli or cerebrovascular accident
what is Thrombocytopenia?
a condition where there are too few platelets in the blood, which can make it harder for blood to clot.
whats a symptom of thrombocytopenia?
petechiae (small, red or purple spots on the skin caused by tiny blood vessels breaking)
what’s the cause of thrombocytopenia?
suppression or destruction of red bone marrow
whats the treatment of thrombocytopenia?
platelet transfusion
what does impaired liver function mean?
that the liver can’t produce enough clotting factors
what are some causes of impaired liver function?
vitamin K deficiency, hepatitis, cirrhosis
what is hemophilia?
a genetic condition where the blood doesn’t clot properly due to a lack of certain clotting factors, leading to excessive bleeding
Two of three types of hemophilia are X-linked, meaning they are passed down through the X chromosome and occur mostly in —.
males
what are two symptoms of hemophilia?
prolonged bleeding after minor injuries and repeated bleeding into joint
what are two treatments of hemophilia?
fresh plasma transfusions; injections of clotting factors
— stabilizes the forming platelet plug, while — reinforces the plug
vWF (von Willebrand factor); fibrin
what two growth factors are involved in blood vessel repair?
vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF).
The enzyme that dissolves clots is —
plasmin