Circulatory system

Question 1

why do we need a circulatory system

Answer 1

for transportation of useful substances to body cells and to carry waste substances away from the body

Question 2

useful substances

Answer 2

oxygen , water and digested fod

Question 3

waste substances

Answer 3

urea , carbon dioxide

Question 4

what is the function of the blood , blood vessels and heart

Answer 4

blood - transport substances around the body
blood vessels- tubes that carries the blood
heart- pumps the blood around the body

Question 5

what is blood composed of

Answer 5

red blood cells, white blood cells and platelets

Question 6

what is plasma and state 3 functions

Answer 6

plasma is the yellow fluid composed of 90% water and makes up 55% of blood. it transports digestive products to the liver from the ileum , urea from liver to kidneys and and hormones from glands to target organs

Question 7

serum

Answer 7

plasma minus clotting factors

Question 8

blood clotting

Answer 8

platelets in blood become spiky and stick close together and release an enzyme called thromboplastin together with calcium and vitamin k which coverts inactive plasma to thrombin which is then coverts plasma proteins into fibrin which forms a network across the cut and eventually dries and forms a scalp

Question 9

blood groups

Answer 9

a, b, ab , o

Question 10

blood vessels

Answer 10

veins . arties and capillaries

Question 11

Arties

Answer 11

these transport blood from the heart to the body at high pressure very rapidly and only carries oxygenated blood with exception of the pulmonary arties. they lie deep in the body and have no valves except the pulmonary artery and aorta. has a narrow lumen and thick layer of muscle

Question 12

capillaries

Answer 12

Transports blood throughout the body and links veins and arties the flow is at a low pressure ad very slow. they have no valves and are one cell thick so substances can pass into them easily

Question 13

veins

Answer 13

transports blood from body to the heart at low pressure and low speed and the blood is deoxygenated besides in the pulmonary vein. THER ARE VALVES TO PREVENT BACKFLOW OF BLOOD. their lumen is wide and the are located close to the surface of the body

Question 14

journey of blood through the heart

Answer 14

anterior/posterior vena cava, right atrium , tricuspid valves , right ventricle, semi lunar valves, pulmonary valves , lungs , pulmonary veins , left atrium , bicuspid valves , left ventricle , semi lunar valves , aorta , body

Question 15

pacemaker

Answer 15

specialised cells that send electrical impulses that travel through the heart causing it to 75 times per minute

Question 16

types of blood pressure

Answer 16

systolic pressure / diastolic pressure

Question 17

why do we need double circulation

Answer 17

the blood losses pressure in lungs and the body

Question 18

causes of heart attacks

Answer 18

fatty material builds up in the coronary artery and blocks oxygen supply

Question 19

causes of hypertension

Answer 19

being over weight , smoking , lack of physical exercise and stress

Question 20

symptoms of a heart attack

Answer 20

chest pains, shortness of breath and dizziness

Question 21

lymph

Answer 21

transport medium which is colour less and forms from tissue fluids and flows from tissues to the heart

Question 22

functions of lymph

Answer 22

removes body waste around body cells, helps maintain normal blood pressure

Question 23

lymph nodes

Answer 23

these filter dead cells and cancerous cells out of lymph and release lymphocytes in time of infection