BLOOD

Plasma

Red blood cell

White blood cell

Platelets

Formed Elements

• ____________ = red blood cells (RBCs)

• __________ = white blood cells (WBCs)

• ____________ = cell fragments

Erythrocytes (Red Blood Cells)

The main function is to _____________

Anatomy of circulating erythrocytes◦Biconcave disks◦Essentially bags of hemoglobin◦ _______________ (no nucleus)◦Contain very few organelles; lack

mitochondriaOutnumber white blood cells 1000:1

Hemoglobin (Hb)

__________-containing protein

Binds strongly, but reversibly, to ______Each hemoglobin molecule has four

oxygen binding sites

Each erythrocyte has 250 million hemoglobin molecules

When there is a high concentration of oxygen (ex. in the lung) hemoglobin combines with oxygen to form oxyhemoglobin. When the blood reaches the tissue which have a low concentration of oxygen the hemoglobin dissociates with the oxygen and the oxygen is released into body tissues

Leukocytes (White Blood Cells)

Crucial in the body’s defense against disease

These are complete cells, with a __________ and ____________

Able to move into and out of blood vessels (_____________)

Can move by ameboid motionCan respond to chemicals

released by damaged tissues – _______________

Leukocyte Levels in the BloodNormal levels are between 4,000 and 11,000 cells per millimeter

Abnormal leukocyte levels◦Leukocytosis

Above 11,000 leukocytes/ml Generally indicates an infection

◦ Leukopenia Abnormally low leukocyte level Commonly caused by certain drugs

Types of LeukocytesGranulocytes

◦Granules in their cytoplasm can be stained

◦ Include:

Types of LeukocytesAgranulocytes

◦ Lack visible cytoplasmic granules◦ Include:

GranulocytesNeutrophils (most common)

◦Multilobed nucleus with fine granules◦Act as _________ at active sites of

infectionEosinophils (not a common WBC)

◦Large brick-red cytoplasmic granules◦Found in response to ____________

and_________________

GranulocytesBasophils (not a common WBC)

◦Have _______________-containing granules

◦Initiate ____________; involved in ________

AgranulocytesLymphocytes (second most

common WBC)◦Two types play an important role in

the_______________ B-cells – produce antibodies T-cells – direct immune response

AgranulocytesMonocytes

◦Largest of the white blood cells◦Function as ________________◦Important in fighting chronic

infection

PlateletsDerived from ruptured

multinucleate cells called __________________

Needed for the clotting processNormal platelet count =

300,000/mm3

Hematopoiesis_______________ formation occurs

in ____________ bone marrowAll blood cells are derived from a

common stem cell - ______________Hemocytoblast differentiation

◦_________ stem cell produces lymphocytes◦_________ stem cell produces other formed elements

Fate of ErythrocytesUnable to divide, grow, or

synthesize proteinsWear out in _____________________When worn out, are eliminated

by____________ in the _______ or _____

Lost cells are replaced by division of hemocytoblasts

Control of Erythrocyte ProductionRate is controlled by a hormone -

___________________________ produce most

erythropoietin as a response to reduced oxygen levels in the blood

Homeostasis is maintained by __________ feedback from blood oxygen levels

Control of Erythrocyte Production

http://people.sinclair.edu/normahollebeke/107/Blood%20Worksheet.pdf