vascular system

Question 1

What is the pulmonary system

Answer 1

takes deoxygenated blood from the heart to the lungs and oxygenated blood back to the heart

Question 2

what is the systemic system

Answer 2

takes oxygenated blood to the body from the heart and then the return of deoxygenated blood from the body to the heart

Question 3

what are the 5 different blood vessels in the body

Answer 3

Heart -> Arteries -> arterioles -> capillaries -> venules -> veins -> heart

Question 4

how do you work out blood pressure

Answer 4

blood pressure = blood flow x resistance

Question 5

what is systolic pressure

Answer 5

this is where the heart contracts - blood is forced out under high pressure

Question 6

what is diastolic pressure

Answer 6

where the ventricles relax and lower pressure

Question 7

how do you measure blood pressure

Answer 7

12o mmHg / 80 = milimetres of mercury

Question 8

what happens if the pressure in the lungs is low?

Answer 8

this makes it hard to return blood to the heart. the larger lumen offers little resistance to blood flow.

Question 9

what mechanics are needed if pressure in the veins is low

Answer 9

The skeletal muscle pump
the respiratory pump
pocket valves

Question 10

what is the skeletal muscle pump

Answer 10

muscles contracting and relaxing pressing on nearby veins causing a pumping effect. this squeezes the blood back to the heart

Question 11

what is the respiratory pump

Answer 11

when muscles contract during breathing in and out pressure changes occur in the thoracic and abdominal cavities. this compresses nearby veins and assists blood flowing back.

Question 12

what are pocket valves

Answer 12

it is important that blood in veins only flows in one direction. valves ensure this happens. They close once blood has passed through to prevent blood from flowing back.

Question 13

what are other factors thatr aid venous return

Answer 13

very thin layer of smooth muscle on vein walls, which help to squeeze blood back into the heart.

gravity helps blood from the upper body return to the heart
the suction pump action of the heart

Question 14

what is the equation of venous return

Answer 14

venous pressure - right atrial pressure / venous vascular resistance

Question 15

How is oxygen transported transported by

Answer 15

During exercise, oxygen diffuses into the capillaries to serve the skeletal muscles.

3% dissolves into the plasma, 97% combines with haemoglobin to form oxyhaemoglobin.

when fully saturated haemoglobin will carry oxygen molecules.

this happens when partial pressure of oxygen in the blood is high

At the tissues, oxygen is released from the oxyhaemoglobin due to lower pressure of oxygen in the tissues - this is known as oxygen dissociation

In the muscle oxygen is stored in the mitochondria until it is used by the muscles

mitochondria are the centres in the muscles where aerobic respiration takes place.

Question 16

what happens to the oxyhaemoglobin dissociation curve.
what is the Bohr shift

Answer 16

Durine exercise, the s-shaped curve shifts to the right because when muscles require more oxygen, the dissociation of oxygen from haemoglobin in the blood capillaries to the muscle tissues occur more efficently - this is known as Bohr shift

Question 17

what are three factors are responsible for the Bohr shift

Answer 17

increase in blood temperature
partial pressure of carbon dioxide increases
PH - more carbon dioxide lower blood PH

Question 18

Redistribution of blood?

what happens if you eat a meal before a competition?

Answer 18

a full gut would result in more blood being directed to the stomach.
less blood being redirected to the working muscles
detrimental affect on performance as less oxygen is available

Question 19

where is the vasomotor centre located and what does it control

Answer 19

the vasomoter is found in the medulla oblongata of the brainand helps to control both blood pressure and blood flow.

Question 20

what doe chemoreceptors do?

Answer 20

they detect chemical changes e.g increased carbon dioxide and lactic acid. they send a signal to the vasomotor centre which redistributes blood to flow through

Question 21

what happens when sympathetic stilumation increases

Answer 21

vasoconstriction occurs

Question 22

what happens when sympathetic stimulation decreases

Answer 22

vasoldilation occurs

Question 23

why is the redistribution of blood important

Answer 23

increases the supply of oxygen to the working muscles
removes waste products from the muscles, such as carbon dioxide and lactic acid
Ensure more blood goes to the skin during exercise
direct more blood to the heart during exercise.

Question 24

what is arterio- venous oxygen difference

Answer 24

the difference between the oxygen content of the arterial blood arriving at the muscles and the venous blood leaving the muscles.

Question 25

what is the difference of the arterio-venous oxygen when it is low and then during exercise

Answer 25

at rest the arterio venous differenc is low not as much oxygen is required to the working muscles.

but during exercise as more oxygen is needed for the working muscles the arterio venous difference is high