10.2 Blood Flashcards
what is the function of blood (3)
- transports nutrients, wastes, hormones
- regulatates blood temp by dispersing body heat and helps regulate blood pressure because plasma proteins contribute to osmotic pressure of blood
- protect body against invasion by disease causing pathogens
additional notes:
- buffers in blood maintain pH around 7.4
- clotting mechanisms protect body against potentially life threatening loss of blood
describe the layers of blood
55%: PLASMA liquid portionof blood
45% FORMED ELEMENTS: thrombocytes and leukocytes (middle layer), erthrocytes (bottom layer)
describe the components of plasma (function + source)
90-92% WATER f: maintains blood volume, transports molecules, s: absorbed from intestine
7-8% PLASMA PROTEIN f: maintain blood osmotic, pressure, pH; maintains blood volume, pressure, transport. s: liver, B lymphocytes, Liver
<1% SALTS f: maintain blood osmotic pressure and pH, aid metabolism. s: absorbed form intestines
GASES: cellular respiration, end of product metabolism. s: lungs, tissues
NUTRIENTS: f: food for cells. s: absrbed from intestines
NITROGENOUS WASTE. f; excretion by kidneys. s: liver
OTHER (HORMONES, VITAMINS) f: aid metabolism, s: varied
why does blood in capillaries have a higher solute concentration
plasma proteins also maintain blood volume because they are too large to leave capillaries therefore water automatically diffuses into them
describe erythrocytes
f: transports O2 help transports CO2
s: red bone marrow of skull, ribs, vertebrae, ends of long bones
- no nucleus, bio concave disk
describe the shape of erthrocytes
shape increases flexibility for moving through capillary beds and surface area for diffusion of gases
why do erythroycytes carry oxygen
they contain hemoglobin ( respiratory pigment)
- hemoglobin is a red pigment that contains four polypeptide chains
- each chain is associated w a heme (iron containing group)
- iron portion of hemoglobin acquires oxygen in lungs and give it ups in tissues
what is the lifeline of erythrocyte
- live only 120 days because lack nuclei
- destroyed mainly in liver and spleen where they are engulfed by large phagocytic ce;;s
- iron salvaged and reused while heme portion undergoes chemical degradation and liver excretes it into bile as bile pigments
what is anemia
three causes
- decreased production of RBC
- loss of RBC from body
- destruction of RBC within body
- tired rundown feeling
what is iron defiency anemia
RBC production decreased bc diet not enough iron
what happens in chronic anemia or when a person takes up high alititude
-reduced amount of O2, kidney increase their production of erythropoietin (hornome) which speeds up maturation of RBC in bone marrow
describe leukocytes
- larger than RBC, have nucleus, lack hemoglobin, without staining appear transulucent
f: WBC fight infections, development of immunity, resist diseases
what are the 2 types of WBC
- granular leukocytes: neutrophils (multilobed nucleus), eosinophils (deep red fight parasitic worms), basophils(deep blue release histamine)
- agranular leukocytes: monocytes (phagocytic dendritic cells and macrophages) and lymphocytes
what are dendritic cells and macrophages
- monocytes (agranular leukocytes)
- dendritic cells: present in tissues in contact w environment : skin, nose, lungs, intesttine. once they capture microbe w dendritesm stimulate WBC to defend body
- macrophages: phagocyte
what are lymphocytes
- agranular leukocyte
- B lymphocyte produce antibodies, T lymphocyte (helper regulate response of other cells) (cytotoxic lymphocytes kill other cells)
