Topic 8: Blood and bone marrow

blood

specialized CT

cells, fluid extracellular matrix

blood consists of?

fluid extracellular material

plasma is called?

blood

o Propelled by rhythmic contraction of the heart

o Average Volume: 5L

Erythrocytes

leukocytes

platelets

formed elements of blood:

blood

1. Transport nutrients, oxygen, wastes, and carbon dioxide to and from

the tissues.

2. To convey hormones, cytokine, chemokines, and other soluble

regulatory molecules.

3. To transport leukocytes and antibodies through the tissues.

4. To maintain homeostasis.

albumin

Serves to maintain the osmotic pressure of the blood;

transport insoluble metabolites.

globulins

Transport metal ions; protein-bound lipids,

lipid-soluble vitamins.

immunoglobulins (antibodies or y-globulins)

Secreted by plasma cells; antibodies for host defense

complement proteins

comprise a defensive system important in inflammation and destruction of microorganisms

clotting factors

formation of blood clots

plasma lipoproteins

Transport of triglycerides and cholesterol to/from the liver.

water

is the solvent in which formed elements are suspended and proteins and solutes are dissolved

plasma proteins

all proteins serve to buffer against pH charges

albumin

exerts osmotic force to retain fluid within the microvasculature

contribute to bloods viscosity

binds and transports some fatty acids, electrolytes, hormones and drugs

fibrinogen

participants in blood coagulation, precursor of fibrin

regulatory proteins

consists of enzymes, proenzymes, hormones and the complement system

electrolytes

help establish and maintain membrane potentials, maintain pH balance and regulate osmosis

nutrients

energy source, precursor for synthesizing other molecules

respiratory gases

oxygen is needed for aerobic cellular respiration, carbon dioxide is a waste product produced by cells during this process

wastes

serve no function in the blood plasma; they are merely being transported to the liver and kidneys where they can be removed from the blood

Erythrocytes (RBC)

life span in blood: 120 days

RBC at angles of capillary bifurcations

assume a cuplike shape

RBC at angels of capillary vessels

dheres to one another loosely in stacks called rouleaux

peripheral microtubule bundle

maintains shape

actin and myosin

clot contraction

Thrombocytes (platelets)

life span in blood: 10 days

neutrophils

life span in blood: < 1 week

eosinophils

life span in blood: <2 weeks

basophils

life span in blood: 1-2 years

monocytes

life span in blood: few days in blood, several months in CT

lymphocytes

life span in blood: variable (few days to several years)

megakaryocyte

develop into large polyploidy cells that

remain transcriptionally active and extrude platelets as

cytoplasmic fragments directly into marrow sinus.

future granulocytes

produce specific and non-specific granules, and

then shape their nucleus.

future monocytes

produce non-specific granules and shape their

nucleus.

future small lymphocytes

decrease their size and enter the blood, but

then undergo further maturation at another site

future erythocytes

fill cytoplasm with hemoglobin, synthesized on

free polysomes (ribosomes on mRNA), and eventually extrude their

nucleus.