Blood

Question 1

What are the functions of blood?

Answer 1

Transport dissolved gases, nutrients, hormones
Buffer
Protection against toxins and pathogens
Stabilize body temp

Question 2

Composition of blood

Answer 2

Water
Nutrients
O2
Co2
Proteins

Question 3

What are erythrocytes

Answer 3

Transport o2 in blood

Question 4

Can get blood cells repair themselves?

Answer 4

No they die in 120 days

Question 5

What are leukocytes

Answer 5

Body’s defence mechanisms

Question 6

What are thrombocytes?

Answer 6

Platelets

Involved in clotting

Question 7

What do leukocytes do?

Answer 7

Defend the body against pathogens

Question 8

What do thrombocytes do?

Answer 8

They stick to damaged vessel walls to form haemostatic plug

Constrict the vessel and release chemicals to initiate clot reaction

Question 9

What are the four chambers of the heart?

Answer 9

Left atrium
Left ventricle
Right atrium
Right ventricle

Question 10

What are the four valves

Answer 10

Bicuspid
Triscuspid
Mitral
Aortic

Question 11

What is the resting heart rate and why?

Answer 11

Around 70bpm because the heart is under vagal restraint

Question 12

What is cardiac output?

Answer 12

Volume of blood pumped through the circulatory system per minute

Question 13

Veins..

Answer 13

Takes blood towards the heart

Question 14

Arteries..

Answer 14

Takes blood away from the heart

Question 15

Describe the flow of blood through the heart?

Answer 15

Blood goes into right atrium via superior vena cava and inferior vena cava
Blood goes into right ventricle via the tricuspid valve
Then goes through the pulmonary valve and splits into left and right pulmonary arteries into the left and right lungs
In the lungs it picks o2 and gets rid of co2
Blood comes back in the left atrium via the left and right pulmonary veins
Blood goes into the left ventricle via the bicuspid valve
Blood passes through the aortic valve to the aorta and then to the rest of the body

Question 16

Describe the electrical system of the heart

Answer 16

In the right atrium, the cells in the sinoatrial node depolarize
When these cells depolarize, they send out waves of depolarization
So all the neighbouring cells start depolarizing in the right atrium and left atrium (via bachmanns bundle in the left atrium)
More bands of tissue like the bachmanns bundle travel to the atrial ventricular node which connects the atria and ventricles
In the AV node, there is a delay between an atrial contraction and ventricle contraction.
If the atrial and ventricles contract simultaneously, they would be squeezing blood against eachother
So the delay allows blood to move from the atria to the ventricles after the atria contracts and then the ventricles can contract and move the blood onwards
The signal continues onto the bundle of His
Through left and right bundles
Signal goes to purkinje fibres and goes off in all directions