Blood

Blood is the fluid through which gases, waste products, nutrients and hormones are transported throughout the body.

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The average human body contains 5L of blood.

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4 Components of the Blood

Blood is made up of 4 Components

1. Plasma
2. Erythrocytes (Red Blood Cells)
3. Leukocytes (White Blood Cells)
4. Platelets

Plasma makes up 55% of the blood and blood cells (erythrocytes, leukocytes, and platelets) make up 45% of the blood.

Components of Blood: Plasma

Structure and Function:

-Fluid medium through which the solid blood components, and other molecules (dissolved gasses, nutrients, wastes, and hormones) are transported around the body

-Contain proteins necessary

for blood clotting, and antibodies

which are necessary for providing

immunity for diseases such as

the measles.

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Components of the Blood: Erythrocytes (Red Blood Cells)

Structure and Function:

• Contains hemoglobin (a molecule that enables the cell to bind Oxygen molecules)
• Erythrocytes not have a nucleus allowing the cell to carry increased hemoglobin

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Components of the Blood: Leukocytes (White Blood Cells)

Structure and Function:

• Protect the body against invading microorganisms and toxins
• Destroy microorganisms by engulfing and digesting them
• Produce antibodies which protect the organism against microorganisms and

play a large role in the immune

system

• Contain a nucleus

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Components of the Blood: Platelets

Structure and Function:

• Fragments of larger cells produced in the bone marrow
• Function to initiate blood clotting
• When platelets encounter a sharp edge (from a cut) they rupture which releases a substance that reacts with proteins in the plasma to create a mesh of fibers
• Fiber mesh prevents further blood flow

Components of the Blood: Platelets

Discussion Questions

1. Patients with hemophilia can lose large amounts of blood from a small cut. Affected individuals have mutations in components of their blood that hinders clotting. Which component(s) of the blood (plasma, leukocytes, erythrocytes, or platelets) do you think hemophilia affects? Explain your answer.

Discussion Questions

2. The Human Immunodeficiency Virus (HIV) attacks the white blood cells of an affected individual. How would the reduced numbers of white blood cells impact the health of an HIV positive individual?

Discussion Questions

3. When performing surgery doctors require large amounts of platelets (obtained through blood donation). Why do you think platelets would be necessary for a procedure such as open heart surgery?

Discussion Questions

4. Red blood cells lack a nucleus to make room for more hemoglobin. Why would increased hemoglobin in red blood cells be beneficial to a human?

Name that Cell!