Ch25: Blood

Question 1

What are the 4 components of blood?

Answer 1

Plasma
Platelets
Red Blood Cells (RBC’s)
White Blood Cells (WBC’s)

Question 2

Brief description of plasma

Answer 2

-Yellow, liquid part of blood
-Makes up 55% of blood
-Made up of 90% water, 7% proteins and 3% dissolved materials

Question 3

What are the main plasma proteins?

Answer 3

-Antibodies (produced by WBC’s to bind foreign substances)
-Clotting proteins (form blood clots)

Question 4

What is serum?

Answer 4

Plasma from which the clotting proteins have been removed

Question 5

What is the function of plasma?

Answer 5

-To transport dissolved materials like glucose, CO2, hormones etc.
-To transport heat

Question 6

What are other names for RBC’s?

Answer 6

-Red blood corpuscles
-Erythrocytes

Question 7

Where are red blood cells produced?

Answer 7

Bone marrow

Question 8

Describe the structure of RBC’s

Answer 8

-Have a nucleus UNTIL they mature into red blood corpuscles after a few days (No nucleus in maturity)
-No mitochondria
-Very small biconcave discs (for increased surface area to aid diffusion)

Question 9

What protein do RBC’s contain? Describe this protein

Answer 9

-Contains red protein, haemoglobin
-It combines with oxygen to form oxyhaemoglobin

Question 10

Describe the life span of a RBC, and the processes by which th ey are broken down.

Answer 10

-RBC’s live for 4 months before being broken down in the liver and spleen
-When they are broken down, the haemoglobin is stored in the liver (and recycled), and the rest of the cell is converted to bile pigments, bilivirdin and bilirubin

-RBC’s are damaged when they change shape to pass through narrow blood vessels

Question 11

What is the function of RBC’s?

Answer 11

To transport oxygen

Question 12

What causes anaemia and how can it be treated?

Answer 12

-Caused y lack of haemoglobin or red blood cells
-Treated by iron supplements or iron rich foods like green vegetables, red meat

Question 13

What does sickle cell anaemia cause?

Answer 13

Causes blood flow to be blocked

Question 14

What is another name for white blood cells?

Answer 14

Leucocytes

Question 15

Describe WBC’s

Answer 15

-Made in bone marrow
-Have a nucleus
-Less numerous than red blood cells (700 red : 1 white)

Question 16

What is the function of white blood cells?

Answer 16

-To defend against and fight infection

Question 17

What are 2 types of WBC’s?

Answer 17

-Lymphocytes
-Monocytes/macrophages

Question 18

Lymphocytes:
1. Where are they produced
2. Percentage that they make up
3. Length of time they survive for
4. Description of structure
5. Where are they stored

Answer 18

1. Made in bone marrow
2. 25%
3. 3 months to 10 years
4. Large; round nucleus; very little cytoplasm
5. Mature in and stored in lymphatic tissue

Question 19

Monocytes/Macrophages
1. Where are they produced
2. Percentage that they make up
3. Length of time they survive for
4. Description of structure

Answer 19

1. Bone Marrow
2. 5%
3. 6-9 days
4. Kidney-shaped nuclei

Question 20

What is the function of lymphocytes?

Answer 20

To make antibodies

Question 21

What is the function of monocytes?

Answer 21

-To surround and digest bacteria and viruses in a process called phagocytosis

Question 22

What is leukemia and how can it be treated?

Answer 22

-A form of cancer in which the WBC’s are produced too rapidly and are immature
-They crowd out other blood cells and may cause anaemia, increased risk of infection and reduced ability to clot
-Treated by radiation or drugs

Question 23

What is another name for platelets?

Answer 23

Thrombocytes

Question 24

How are platelets made?

Answer 24

Made in bone marrow from large cells which break into fragments called platelets

Question 25

What is the fnction of platelets?

Answer 25

-To clot the blood (using a strong platelet plug with stable fibrin mesh) -This reduces blood loss and stops microorganisms from entering

Question 26

What is haemophilia?

Answer 26

-The lacking ability to form a clot, leading to excessive bleeding -Lack of natural clotting factor means only a weak platelet plug can form -Incomplete fibrin mesh allows the bleeding to continue

Question 27

How is a blood clot formed? What do blood clots cause?

Answer 27

Formed if vessel walls are damaged, leading it to be blocked Blood clots are also called a thrombosis -In the brain, causes stroke -In the heart, causes heart attack

Question 28

What are the overall functions of blood?

Answer 28

-Transport food, waste and hormones -Transport heat -Transport oxygen -Defence against disease (WBC’s engulf bacteria, Lymphocytes produce antibodies, platelets clot blood)

Question 29

What is an antigen?

Answer 29

A chemical marker that can stimulate the production of antibodies

Question 30

Where are antigens on RBC’s?

Answer 30

Most RBC’s have a carbohydrate/protein molecule on their surface that acts as an antigen

Question 31

What are the 4 main blood types and how do they differ?

Answer 31

A, B, AB, O -They differ in the type of antigens they have on their RBC’s, e.g. blood type B has B antigens, therefore has antibodies for A (not compatible with blood type A)

Question 32

Why are blood groups important?

Answer 32

Important in blood transfusions, because introducing the wrong antigen may cause blood clumping in the receiver

Question 33

Name the 2 blood grouping systems

Answer 33

-ABO Blood groups -Rhesus factor

Question 34

Explain the rhesus factor

Answer 34

-If somebody is Rhesus Positive (RH+), they have an antigen called factor D -Rh- people will produce antibodies to Factor D -Rh- blood can be given to a Rh+ person -Rh+ blood cannot be given to a Rh- person because the Rh- person has antibodies for the Rh+ blood (causes clumping in blood)

Question 35

Explain how Rhesus factor can impact pregnancy and what can be done to prevent this?

Answer 35

-May lead to problems for a Rh- mother who is pregnant with her Rh+ child -1st Rh+ baby is born safely -Any further born Rh+ babies may be anaemic, brain-damaged or stillborn -Anti-D treatment is used to prevent this