blood

anemia

Anemia is a disease that occurs when there is not enough hemoglobin (or iron) in the blood so it cant carry adequate oxygen to the cells. There are many possible causes of anemia. One possible cause is excessive blood loss due to an injury or surgery. Not getting enough iron in the diet is another possible cause.

diseases of the blood

Some diseases affect mainly the blood or its components. They include anemia, leukemia, hemophilia, and sickle- cell disease.

rhesus blood type

Another red blood cell antigen determines a persons Rhesus blood type. This blood type depends on a single common antigen, typically referred to as the Rhesus (Rh) antigen. If your red blood cells carry the Rhesus antigen, you have Rhesus-positive blood, or blood type Rh+. If your red blood cells lack the Rhesus antigen, you have Rhesus-negative blood, or blood type Rh-.

functions of blood

The main function of blood is transport. Blood in arteries carries oxygen and nutrients to all the bodys cells. Blood in veins carries carbon dioxide and other wastes away from cells to be excreted. Blood also transports the chemical messengers called hormones to cells throughout the body where they are needed to regulate body functions. Blood has several other functions as well. For example, blood: defends the body against infections. repairs body tissues. controls the bodys pH. helps regulate body temperature.

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blood components

Blood consists of both liquid and cells. The liquid part of blood is called plasma. Plasma is a watery, golden-yellow fluid that contains many dissolved substances. Substances dissolved in plasma include glucose, proteins, and gases. Plasma also contains blood cells. There are three types of blood cells: red blood cells, white blood cells, and platelets. You can see all three types in Figure 18.8. 1. Red blood cells are shaped like flattened disks. There are trillions of red blood cells in your blood. Each red blood cell has millions of molecules of hemoglobin. Hemoglobin is a protein that contains iron. The iron in hemoglobin gives red blood cells their red color. It also explains how hemoglobin carries oxygen. The iron in hemoglobin binds with oxygen molecules so they can be carried by red blood cells. 2. White blood cells are larger than red blood cells, but there are far fewer of them. Their role is to defend the body in various ways. For example, white blood cells called phagocytes engulf and destroy microorganisms and debris in the blood. 3. Platelets are small, sticky cell fragments that help blood clot. A blood clot is a solid mass of cell fragments and other substances that plugs a leak in a damaged blood vessel. Platelets stick to tears in blood vessels and to each other, helping to form a clot at the site of injury. Platelets also release chemicals that are needed for clotting to occur.

abo blood type

ABO blood type is determined by two common antigens, often called antigen A and antigen B. If your red blood cells carry only antigen A, you have blood type A. If your red blood cells carry only antigen B, you have blood type B. If your red blood cells carry both antigen A and antigen B, you have blood type AB. If your red blood cells carry neither antigen A nor antigen B, you have blood type O.

blood type

Red blood cells carry proteins called antigens on their surface. People may vary in the exact antigens their red blood cells carry. The specific proteins are controlled by the genes they inherit from their parents. The particular antigens you inherit determine your blood type. Why does your blood type matter? Blood type is important for medical reasons. A patient cant safely receive a transfusion of blood containing antigens not found in the patients own blood. With foreign antigens, the transfused blood will be rejected by the persons immune system. This causes a reaction in the patients bloodstream, called agglutination. The transfused red blood cells clump together, as shown in Figure 18.9. The clumped cells block blood vessels and cause other life-threatening problems. There are many sets of antigens that determine different blood types. Two of the best known are the ABO and Rhesus antigens. Both are described below. You can also learn more about them by watching this video:

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hemophilia

Hemophilia is a genetic disorder in which blood fails to clot properly because a normal clotting factor in the blood is lacking. In people with hemophilia, even a minor injury can cause a life-threatening loss of blood. Most cases of hemophilia are caused by a recessive gene on the X chromosome. The disorder is expressed much more commonly in males because they have just one X chromosome.

sicklecell disease

Sickle-Cell Disease is another genetic disorder of the blood. It is more common in people with African origins because it helps protect against malaria. Sickle-cell disease occurs in people who inherit two copies of the recessive mutant gene for hemoglobin. The abnormal hemoglobin that results causes red blood cells to take on a characteristic sickle shape under certain conditions. You can compare sickle-shaped and normal red blood cells in Figure 18.10. The sickle-shaped cells get stuck in tiny capillaries and block blood flow. This causes serious, painful symptoms. Watch this video animation to learn more about the genetic basis of sickle-cell disease:

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structure and functions of blood

Blood is a liquid connective tissue. It circulates throughout the body via blood vessels due to the pumping action of the heart. You couldnt survive without the approximately 4.5 to 5 liters of blood that are constantly being pumped through your blood vessels.

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leukemia

Leukemia is a type of cancer in which bone marrow produces abnormal white blood cells. The abnormal cells cant do their job of fighting infections. Like most cancers, leukemia is thought to be caused by a combination of genetic and environmental factors. It is the most common cancer in children.

instructional diagrams

No diagram descriptions associated with this lesson

questions

Blood plasma is a

a. chemical that helps blood clot.

-->  b. golden-yellow liquid in blood.

c. disorder in which the blood lacks oxygen.

d. protein carried by red blood cells.

Plasma carries dissolved substances such as glucose and proteins.

-->  a. true

b. false

There are more white blood cells than red blood cells in normal blood.

a. true

-->  b. false

Which statement about red blood cells is false?

-->  a. They are spherical in shape.

b. There are trillions of them in normal blood.

c. They contain iron.

d. none of the above

What are phagocytes?

a. cell fragments that form blood clots

-->  b. white blood cells that engulf microorganisms

c. proteins that bind with oxygen in the blood

d. molecules that determine blood type

Phagocytes are cells that help form blood clots.

a. true

-->  b. false

The main function of blood is transport.

-->  a. true

b. false

All of the following are normal functions of blood except

a. controlling the bodys pH.

b. repairing body tissues.

c. helping regulate body temperature.

-->  d. causing agglutination.

Your ABO blood type is controlled by genes you get from your parents.

-->  a. true

b. false

Which disease of the blood is a form of cancer?

a. hemophilia

b. anemia

-->  c. leukemia

d. sickle-cell disease

One cause of anemia is lack of iron in the diet.

-->  a. true

b. false

Hemophilia is more common in females than in males.

a. true

-->  b. false

__solid mass of cell fragments and other substances that plugs a leak in a blood vessel

a. blood type

b. hemophilia

c. sickle-cell disease

-->  d. blood clot

e. anemia

f. platelet

g. leukemia

__condition in which blood does not have enough hemoglobin (or iron) to carry adequate oxygen to

a. blood type

b. hemophilia

c. sickle-cell disease

d. blood clot

-->  e. anemia

f. platelet

g. leukemia

__type of cancer in which bone marrow produces abnormal white blood cells

a. blood type

b. hemophilia

c. sickle-cell disease

d. blood clot

e. anemia

f. platelet

-->  g. leukemia

__genetic disorder in which abnormal hemoglobin causes red blood cells to change shape

a. blood type

b. hemophilia

-->  c. sickle-cell disease

d. blood clot

e. anemia

f. platelet

g. leukemia

The cardiovascular system normally contains about 2.5 liters of blood.

a. true

-->  b. false

Antigens on your red blood cells determine your blood type.

-->  a. true

b. false

__small, sticky cell fragment that helps blood clot

a. blood type

b. hemophilia

c. sickle-cell disease

d. blood clot

e. anemia

-->  f. platelet

g. leukemia

Dissolved substances in blood include red and white blood cells.

a. true

-->  b. false

__classification of an individuals blood based on its red blood cell antigens

-->  a. blood type

b. hemophilia

c. sickle-cell disease

d. blood clot

e. anemia

f. platelet

g. leukemia

__genetic disorder in which blood is lacking a normal clotting factor

a. blood type

-->  b. hemophilia

c. sickle-cell disease

d. blood clot

e. anemia

f. platelet

g. leukemia

One cause of anemia is excessive loss of blood due to injury or surgery.

-->  a. true

b. false

Blood in veins carries oxygen and nutrients to all the cells of the body.

a. true

-->  b. false

How much blood does your cardiovascular system normally contain?

a. 3.54.0 liters

-->  b. 4.55.0 liters

c. 5.56.0 liters

d. 6.57.0 liters

Blood consists of

a. plasm

b. cells and cell fragments.

c. dissolved substances.

-->  d. all of the above

How does blood carry oxygen molecules?

-->  a. Iron in hemoglobin binds with them.

b. White blood cells engulf them.

c. Platelets stick to them.

d. none of the above

What does blood in veins carry?

a. oxygen

b. carbon dioxide

c. cellular wastes

-->  d. two of the above

Which genotype produces blood type A?

-->  a. AO

b. AB

c. OO

d. none of the above

The blood of a person with leukemia cannot

a. carry enough oxygen.

-->  b. fight infections.

c. clot normally.

d. two of the above

A person with sickle-cell hemoglobin is resistant to

a. blood clots.

b. heart disease.

-->  c. malaria.

d. hemophilia.

diagram questions

No diagram questions associated with this lesson