Sec 30.5: Blood

Question 1

What is blood?

Answer 1

It is a sticky mixture of cells, cell fragments, and fluid, along with particles of fat, other nutrients, and dissolved gasses

Question 2

What is plasma?

Answer 2

It is a clear pale yellow fluid that makes up about 55% of the blood - made up of 90% water

Question 3

What happens to molecules in the plasms?

Answer 3

They dissolve and can be transported throughout the body (i.e. amino acids, glucose, hormones, vitamins, salts, and waste products)

Question 4

Why is plasma important?

Answer 4

Because the concentration of molecules dissolved in it determines which substances will diffuse in and out of blood in capillaries

Question 5

How is homeostasis maintained?

Answer 5

The movement of water, gases, nutrients, and ions between capillaries and cells, as well as plasma proteins, maintain it

Question 6

What are examples of plasma proteins?

Answer 6

Albumin, Fibrinogen, and immune proteins

Question 7

What is albumin?

Answer 7

It is the most abundant plasma protein (the same substance as in egg white)

Question 8

What is the main role of albumin?

Answer 8

To stabilize blood volume so that fluid in the blood does not leak out of the vessels

Question 9

What is fibrinogen?

Answer 9

It is a clotting factor that works with platelets to stop the bleeding after an injury.

Question 10

How much of all cells in the blood do red blood cells make up?

Answer 10

They make up 40-45% of all cells in the blood

Question 11

What are mature RBCs shaped like? What are they produced from?

Answer 11

They are shaped like an inner tube with a solid center. They are produced from stem cells in bone marrow

Question 12

Why do RBCs lose their nuclei?

Answer 12

They gradually fill with hemoglobin and lose their nuclei and other organelles at they mature, so they can no longer divide

Question 13

What are degraded cells and how long do RBCs circulate before becoming ones?

Answer 13

Degraded cells are discarded RBCs that are carried to the liver and spleen to break up and recycle the cells. The RBCs circulate through the body for about 120 days before degrading.

Question 14

What is the most important function of RBCs?

Answer 14

To transport O2 to the cells and carry CO2 away

Question 15

How is O2 transported to cells?

Answer 15

It binds to the hemoglobin in red blood cells and is transported to all cells

Question 16

What happens to damaged or misshapen RBCs?

Answer 16

They cannot transport O2 effectively.

Question 17

What is sickle cell disease?

Answer 17

RBC are distorted into crescents and transport less O2 and clump in blood vessels (degraded after 10-20 days)

Question 18

What defines blood type?

Answer 18

the surface protein markers on RBC

Question 19

What happens if different protein markers are introduced to a person’s body?

Answer 19

Their immune system will attack the foreign blood cells and cause them to clump, blocking vital blood vessels and resulting in death.

Question 20

What does an AB Blood group mean?

Answer 20

Both protein markers (A & B) are present, so the person can accept any blood type

Question 21

What does an O Blood group mean?

Answer 21

No protein marker is present, so the person can donate to any blood type

Question 22

What does an Rh- factor mean?

Answer 22

Anyone can receive this blood type, but they cannot receive Rh+

Question 23

What are white blood cells?

Answer 23

They are cells that defend the body against infection and remove foreign material and dead cells (no hemoglobin)

Question 24

What do phagocytes do?

Answer 24

They surround and ingest microorganisms

Question 25

What do B-lymphocytes do?

Answer 25

They produce proteins that act to destroy pathogens

Question 26

Are white blood cells limited to the circulatory system?

Answer 26

No, some can pass into lymphatic system and attack pathogens in the body’s tissues

Question 27

What are platelets?

Answer 27

They are cell fragments, produced in bone marrow, that help in blood clotting

Question 28

How do platelets repair injuries?

Answer 28

They form spiky extensions that intertwine into a complex net. “Clotting factors” release proteins to begin repairing
-> converts promothorbin (plasma protein) into thrombin
-> thrombin converts fibrinogen into fibrin
-> sticky threads of fibrin form a web that traps platelets and white blood cells
-> forms a plug/clot on the blood vessel
-> seals the wound and prevents any further loss of blood
-> body increases the rate of change in clotting until the wound is sealed
-> other chemicals are released to dissolve the clot

Question 29

How is clotting that blocks arteries to heart and brain treated?

Answer 29

With medications that thin the blood and dissolve clots

Question 30

What is hemophilia?

Answer 30

It is a genetic disorder in which a key clotting factor is missing in the blood (bruises and scratches can be life-threatening)

Question 31

How is hemophilia treated?

Answer 31

Missing clotting factor is injected into the blood to help seal injuries