Chapter 10 - blood

what can blood transport?

nutrients, wastes, and body head managed through blood cells

why is blood unique?

only fluid tissue; has both solid and liquid components; complex connective tissue

formed elements

living blood cells suspended in plasma; account for 45% of blood sample

plasma

nonliving fluid matrix, makes up 55% of blood, 90% water, straw colored, over 100 different substances dissolve in it, helps distribute heat throughout the body

what would happen if blood was spun in a centrifuge?

heavier formed elements would be at the bottom and the plasma would rise to the top with a layer separating in between

erythrocytes

red blood cells, primarily carry oxygen in blood to all cells in body

buffy coat

thin whitish layer containing leukocytes and platelets (1%) separating plasma and the formed elements

hematocrit

percentage of blood volume of a red blood cell

blood

sticky, opaque fluid with metallic taste

what does the color of blood depend on?

amount of oxygen it is carrying

scarlett (bright) red blood

oxygen rich

dull dark maroon red blood

oxygen poor

blood vs water

heavier and 5 times thicker

what is the pH of blood?

slightly basic/ alkaline; 7.35-7.45

what temperature is blood?

100\.4 F

what is the volume of blood?

accounts for roughly 8% of body weight; 5-6 L or 6 quarts

what are some substances dissolved in plasma?

nutrients, salts, respiratory gas (02 and CO2), hormones, plasma proteins, wastes

plasma proteins

most abundant solute of plasma, made by liver, wide variety of functions

albumin

plasma protein; contributes to osmotic pressure in blood

what is a function of clotting proteins?

help stem blood loss

composition of plasma

varies continuously as cells remove/ add substances to the blood; kept relatively constant by homeostatic mechanisms

how are RBCs different from other cells?

anucleate, contain few organelles; mature ones have sacs of hemoglobin

hemoglobin (Hb)

iron-bearing proteins, transports bulk of oxygen in blood, binds with small amount of CO2

RBCs shape

small biconcave disks; provide for large surface area idea for gas exchange

how many oxygen molecules is an Hb molecule capable of binding to?

4

anemia

a decrease in oxygen carrying ability off the blood

what major problem do people with sickle cell anemia face?

blood clots

polycythemia

an excessive/ abnormal increase in number of erythrocytes; can result from bone marrow cancer or high altitudes; increases blood viscosity and impairing circulation

leukocytes

white blood cells; crucial to body's defense against disease, only "complete" cells in blood

why are leukocytes the only complete cells in bloodd?

they have nuclei and organelles

how do WBCs defend the body?

they form a protective movable army that protects against bacteria, viruses, parasites, and tumor cells

how are leukocytes unique?

they can move in and out of blood vessels

diapedesis

leaping across, walking in and out; the ability of a WBC to move in and out of blood vessels

positive chemotaxis

WBCs can locate areas of tissue damage/ infection in the body by responding to certain chemicals that diffuse from the damaged cells

how many WBCs appear in the blood when they mobilize?

twice as much as the body speeds up production

leukocytosis

count above 11000 cells/mm3, too many cells; indicates infection in the body

leukopenia

lacking white blood cells

what happens in leukemia?

1) bone marrow becomes cancerous & huge numbers of WBCs turnout rapidly 2) new WBCs are immature & incapable of carrying out normal protective functions 3) therefore body becomes easy prey for bacteria and viruses

classification of WBCs

granulocytes & agranulocytes (depending on visible granules)

granulocytes

lobt nuclei, stained specifically with Wrights stain; neutrophils, eosinophils, basophils

neutrophils

smaller phagocyte, show up at sites of acute infection

eosinophils

numbers increase rapidly during allergies and infections by parasitic worms

basophils

rarest of WBCs; contain large histamine containing granules

what does histamine do?

chemical makes blood vessels leaky

agranulocytes

lack visible cytoplasmic granules, nuclei closer to norm (circular); lymphocytes and monocytes

lympthocytes

take up residence in lymphatic tissue, play important role in immune response

monocytes

largest of WBCs; macrophages fight prolonged chronic infections

platelets

not technically cells, fragments of multinucleate cells (megakaryocytes), pinch off into thousands of anucleate pieces sealing off from surrounding fluid

megakaryocytes

large bone marrow cells

what are platelets needed for?

clotting process when blood vessels are ruptured/ broken

where does blood cell formation occur?

red bone marrow