lab: blood n hematocrit

blood is composed of:

• plasma (55%)

• white blood cells and platelets (<1% aka buffy coat)

• red blood cells (45% aka formed elements)

erythrocytes

• red blood cells/RBCs

• biconcave disc

• anucleated

• orange-pink to bright red to dark red colors

• transport oxygen and carbon dioxide

• use hemoglobin to carry oxygen to tissues throughout the body

• most abundant formed element in blood

• 100-120 days lifespan

• sketch what they look like

leukocytes

• white blood cells/WBCs

• have many different immune functions

• can travel out of blood vessels into tissues

• draw what they look like

• granulocytes

  • eosinophils

  • neutrophils

  • basophils

• agranulocytes

  • lymphocytes

  • monocytes

diapedesis

• ability of WBCs to travel out of blood vessels into tissues

• protective function to move in and out of blood vessels

• WBCs wander in body tissues by ameoboid motion to reach sites of inflammation or tissue destruction

platelets

• critical in blood clotting

• not complete cells - cytoplasmic fragments

• originate from megakaryocytes that fragment

• cell fragments of large multinucleate cells (megakaryocytes) formed in bone marrow.

• dark and irregular shaped; provide sketch

megakaryotes

• big

• multinucleated

• fragments into platelets

order of leukocytes from most to least abundant

• Neutrophils

• Lymphocytes

• Monocytes

• Eosinophils

• Basophils

neutrophils

• nucles multilibed; pale red and blue xytoplasmc granules

• phagoxytize pathogens or debris

• aborted-fetus-like nuclei; usually around 3. Multilobed nucleus w/ pale red and blue cytoplasmic granules

eosinophil

• kill parasitic worms; slightly phagocytic; complex role in allergy and asthma

• kidney beans-like nuclei; nucleus bilobed; ;red cytoplasmic granules

basophil

• Release histamine and other mediators of inflammation

• contains heparin, an anticoagulant

• nucleus lobed; large blue-purple cytoplasmic granules

lymphocyte

• mount immune response by direct cell attack or via antibody production

• nucleus is huge, like a small cell w/ big nucleus

• nucleus spherical or indented; pale blue cytoplasm

monocyte

• in tissues, develop into macrophages that phagocytize pathogens or debris

• nucleus U/kidney shaped

how to perform hematocrit

• place capillary tube into blood sample to draw up blood

• centrifuge capillary tube

• measure total length of fluid in tube

• measure in cm, RBCs, WBCs, and plasma from bottom

• calculate total %

• draw ratio of what a hematocrit should look like

hematocrit equation

(height of RBC/heigh of all components of blood) 100

why are hematocrits based on erythrocytes?

• RBCs are respoonsible for carrying oxygen thro out the body

• this indicates how well ur body can transport oxygen

• blood cell population is primarily RBCs; hematocrit generally considered equivalent to RBC volume

what happens to blood in hematocrit?

• after getting centrifuged, blood separates to 3 layers

• most dense layer sinks to bottom

• erythrocyte sinks to bottom, around 45% of blood. The % known as hematocrit

• buffy coat contains leukocytes and platelets (<1%), thin, whitish layer b/w erythrocytes and plasma

• plasma rise to top (55%, 90% water)

why is blood considered a connective tissue?

consists of cells and matrix. Non-living matrix = plasma and cells + cell fragments are formed elements/living.

plasma

• more than 100 substances suspended/dissolved in plasma

• over 90% water

• nutrients, gases, hormones, various wastes, metabolites, proteins, electrolytes

• composition

normal hematocrit ranges

• normal adult female = 37-47%

• normal adult male = 42-52%

• normal newborn = 49-61%

what differs RBCs against other cells?

• they are anucleated when mature and circulating blood

• unable to produce or repair damage

• life span 100-120 days

granulocytes

• have granules in cytoplasm that stain differentially with Wright’s stain; have peculiarly lobed nuclei often consist of expanded nuclear regions connected by thin strands of nucleoplasm

• neutrophils

• eosinophils

• basophils

agranulocytes

• no visibile cytoplasmic granules

• found in blood but more abundant in lymphoid tissue

• lymphocytes

• monocytes

Most abundant to least abundant leukocyte

• “NEVER LET MONKEYS EAT BANANAS”

• neutrophils

• lymphocytes

• monocytes

• eosinophils

• basophils

anemia

• lack of RBCs or hemoglobin

• basically lack of ability to carry o2, whether its bc lack of red blood cells or smt WRONG w those rbcs

• red blood cell may appear pale → indication of decreased hemoglobin content

• RBCs may be nucleated → indication that bone marrow turning out cells prematurely

• hematocrit value below avg

leukocytosis

• leukocyte count too high

• buffy coat constitutes >1%

• caused by infection or some type of leukemia

aplastic anemia

• bone marrow doesn’t produce enough new erythrocyte

iron-deficiency anemia

• erythrocytes are smaller

• smaller erythrocyte = smaller surface area for hemoglobin = less like for bond b/w iron and O2 = less O2 carried n nourish the body

hemolytic anemia

• erythrocytes are destroyed too quickly

• keep dying off quicker so supply of RBCs is low, less media to carry O2 throughout body

sickle cell anemia

• sickle shaped erythrocyte

• funky RBC structure; not biconcaved so area to carry oxygen is not ideal = less oxygen able to circulate w the RBC.

hemorrhagic anemia

• literal blood loss

• NOT detected by hematocrit

• when significant blood is lost, both red blood cells and plasma are lost proportionally, leading to a seemingly normal hematocrit reading until the body re-equilibrates fluid levels by drawing in extravascular fluid, diluting the remaining red blood cells and causing a drop in hematocrit

why do individuals who live in high altitudes have higher hematocrit?

• due to lower O2 lvls at high altitudes, the individuals need to produce more erythrocytes to increase blood oxygen levels

why do babies have higher hematocrit?

• their bodies produce more red blood cells to compensate for low oxygen levels in the womb. This condition is called polycythemia. 

dehydration

• plasma % decreases

• loss of water means less plasma

why do some people have anemia but also a normal hematocrit?

• the problem is not the AMOUNT of RBCs that they have so their hematocrit is normal

• the problem lies in the hemoglobin lvls on RBCs OR funcky red blood cell shapes that affect hemoglobin content and their ability to bind to O2, preventing normal blood oxygen levels

• hemoglobin has heme that combines reversibly with oxygen. Higher hemoglobin content = more o2 able to be transported

hemostasis

• protective mechanism that set into motion when blood vessel breaks

• vascular spasm

• platelet plug formation

• coagulation (blood clotting)

  • interaction b/w many substances such as clotting factors and procoagulants + platelets

  • injured tissues and platelets release tissue factor and phosphatidylserine. Trigger clotting mechanism (cascade)

  • phos wtv the fuck reacts w blood protein clotting factor and calcium ions to form prothrombin activator

  • converts prothrombin in plasma to thrombin

  • thrombin polymerized fibrinogen proteins into insoluble fibrin - form basis of clot

antigen

• agglutinogens

• genetically determined

• accompanied by antibodies

• present on RBCs’ cell membranes

• substance the body recognizes as foreign

• may be attacked by immune system

antibodies

• accompanied by antigens

• present in person’s plasma

• “recognizers”

Rh+ vs Rh-/Rh blood groups

• neither Rh+ or Rh- individuals carry preformed anti-Rh antibodies

• presence of absence of one of 8 rhesus antigens

why can’t Rh+ people donate to Rh- people?

• Rh- people receiving Rh+ blood would be fine the first time, but their body would recognize the Rh antigents and become sensitized to the blood w it.

• Their system begin to produce anti-Rh antibodies

• subsequent exposure to Rh+ blood will result in their own blood clumping and hemolysing the donor’s RBCs

create table of ABO blood typing + blood typing tests

review slides of blood cells and draw sketch + write brief description of each

agglutination

• can also be called precipitation

• antibodies in a person’s body detects specific antigen (present on RBCs)

• cause blood to clump up

ABO blood group

presence or absence of A and B antigen