Circulatory System

Question 1

what is blood

Answer 1

a tissue made of fluid (plasma) with suspended cells due to pressure of cells

Question 2

what percentage of blood is plasma

Answer 2

about 55%

Question 3

what percentage of blood is cellular elements

Answer 3

about 45%

Question 4

what are the 4 main functions of blood

Answer 4

transport of substances protection against pathogens protection against blood loss regulation of pH temperature and water content

Question 5

what is plasma

Answer 5

pale yellow liquid 90% water 10% proteins that transports substances blood cells and platelets

Question 6

what are red blood cells

Answer 6

circular biconcave discs without nucleus containing haemoglobin to transport oxygen

Question 7

what adaptations of red blood cells increase oxygen transport

Answer 7

biconcave shape for surface area absence of nucleus for more haemoglobin haemoglobin binds oxygen reversibly

Question 8

what are white blood cells

Answer 8

irregular-shaped cells with nucleus some can move through capillaries produce antibodies and engulf pathogens

Question 9

what are platelets

Answer 9

fragments of cytoplasm with clotting factors involved in blood clotting

Question 10

why is blood clotting important

Answer 10

prevents excessive bleeding and stops entry of pathogens by sealing vessels

Question 11

what are the 4 blood groups

Answer 11

A B AB O

Question 12

who are universal blood donors

Answer 12

O group

Question 13

who are universal blood recipients

Answer 13

AB group

Question 14

why must transfused blood be compatible

Answer 14

incompatible blood causes immune system to attack donor cells which is life-threatening

Question 15

which blood types can O donate to

Answer 15

all groups

Question 16

which blood types can A donate to

Answer 16

A and AB

Question 17

which blood types can B donate to

Answer 17

B and AB

Question 18

which blood types can AB donate to

Answer 18

AB only

Question 19

which blood types can O receive from

Answer 19

O only

Question 20

which blood types can A receive from

Answer 20

A and O

Question 21

which blood types can B receive from

Answer 21

B and O

Question 22

which blood types can AB receive from

Answer 22

all groups

Question 23

what are arteries

Answer 23

vessels with thick muscular elastic walls carrying blood away from heart at high pressure no valves small lumen fast flow

Question 24

what are veins

Answer 24

vessels with thin walls larger lumen carrying blood towards heart low pressure slow flow valves present to prevent backflow

Question 25

what are capillaries

Answer 25

one-cell thick walls no valves no lumen allow efficient diffusion of oxygen carbon dioxide nutrients and wastes slow flow low pressure

Question 26

describe blood flow pathway

Answer 26

blood from heart flows into arteries then capillaries then veins which return blood to the heart

Question 27

what is tissue fluid

Answer 27

fluid around tissues and cells that supplies oxygen and glucose and receives carbon dioxide and wastes by diffusion

Question 28

where does material exchange occur

Answer 28

only at capillaries through tissue fluid

Question 29

how does diffusion in tissue fluid work

Answer 29

oxygen and nutrients move from blood to tissue fluid to cells while carbon dioxide and wastes move from cells to tissue fluid to blood

Question 30

where is the heart located

Answer 30

centre of chest about fist-sized beating 60-100 times per minute

Question 31

what happens when heart muscles contract

Answer 31

they increase pressure and pump blood through the body ensuring circulation

Question 32

how do heart muscles get oxygen and glucose

Answer 32

through coronary arteries

Question 33

what is coronary heart disease

Answer 33

build-up of fatty deposits narrowing coronary arteries reducing blood supply leading to heart muscle death and possible heart attack

Question 34

why is heart muscle damage permanent

Answer 34

dead heart tissue cannot be repaired so other muscles work harder to pump blood

Question 35

what are 3 risk factors for coronary heart disease

Answer 35

poor diet high in fats smoking or lack of exercise stress and genetic family history

Question 36

what happens when surface antigens meet opposing antibodies

Answer 36

agglutination clumping and hemolysis