Biology B1.P2

Question 1

Blood is responsible for (P21)

Answer 1

-Transporting oxygen from lungs to the body cells for aerobic respiration.

-Delivering nutrients from the intestine to the body cell.

-Also transports hormones from the endocrine glands to their targeted cells.

Question 2

Blood is also responsible for regulating (P2)

Answer 2

-Body temperature

-PH of body tissue

-Volume of fluid concentration

Question 3

4 components of blood are:

Answer 3

-Platelets (Thrombocytes) - helps in blood clot in order to prevent bleeding and entry of pathogen.

-WBC (leukocytes)- defends one from infections.

-RBC (Erythrocytes)- carry blood from lungs and then throughout the body.

-Plasma- dissolves digested food and transports them aswell as CO2 and urea.

Question 4

Plasma transporting digested food

Answer 4

Digestive system breaks down insoluble molecules of food to small soluble molecule for use of energy.

Then the digested food goes from small intestine into blood stream where it is dissolved into the plasma and that transports it.

Question 5

Plasma transporting Carbon dioxide

Answer 5

Co2 goes from body cells into blood where it is dissolved by plasma

Where it then carries it to the lungs, where it is then released.

Question 6

Plasma transporting urea

Answer 6

Made in liver
Urea enters blood in liver and dissolve in plasma which transports it to kidneys.

Question 7

Steps for blood clotting: Platelets (Thrombocytes)

Answer 7

Damage to the endothelium releases clotting factors which goes onto the tear blood vessels and sticks together

Clotting factors convert enzyme, prothrombin to thrombin which causes the plasma protein fibrinogen to form threads
of fibrin

Fibrin threads mesh together clotting the blood and sealing the
wound

Lastly other cells go on it to make it stronger.

Question 8

Atrial systole (contraction of both atria)

Answer 8

Atria is first filled with blood from vena cava/ Pulmonary vein

Then it is contracts and forced trough the atrioventricular valves into the ventricles where it goes to ventricles.

Question 9

Ventricular systole (contraction of both ventricles)

Answer 9

Ventricles then contract forcing blood through the semi-lunar valve to stop backflow into ventricles.

Question 10

Diastole (relaxation of the heart)

Answer 10

As ventricles relaxes the drop in blood causes the SL valves to close and it then starts again with blood filling at the atria.