Structure and Function of Cardio-respiratory system

Question 1

Where does gaseous exchange take place?

Answer 1

Gaseous Exchange takes place in the aveoli.

Question 2

What are the 5 stages for the pathway for air?

Answer 2

• Air enters the body and is warmed as it travels through the mouth and nose.
• It then enters the trachea.
• The trachea divides into two bronchi. One bronchus enters each lung.
• Each bronchus branches out into smaller tubes called bronchioles. Air travels through these bronchioles.
• At the end of the bronchioles, the air enters one of the many millions of alveoli where gaseous exchange takes place.

Question 3

Name 3 characteristics of aveoli?

Answer 3

• they give the lungs a really big surface area
• they have moist, thin walls (just one cell thick)
• they have a lot of tiny blood vessels called capillaries

Question 4

What is the 4 stage process of gaseous exchange?

Answer 4

1) Oxygen that has been breathed in passes through the aveoli (air sacs) and into the red blood cells in the capillaries.
2) The oxygen combines with the haemoglobin to form oxyhaemoglobin.
3) At the same time an enzyme in the red blood cells breaks down the CO2 in the blood and turns it into a gas.
4) The CO2 in the capillaries then passes through the aveoli and into the red blood cells in the capillaries.

Question 5

What does inspiring mean?

Answer 5

Inspiring- Breathing in

Question 6

What does expiring mean?

Answer 6

Expiring- Breathing out

Question 7

What are the mechanics of breathing when your are inspiring?

Answer 7

When you are at rest and inhaling, the diaphragm flattens and moves downwards and the intercostal muscles contract, which raises the ribs up, making the chest cavity larger. This reduces the air pressure inside the chest cavity, which in turns causes air to be sucked into the lungs.

Question 8

What are the mechanics of breathing when you are expiring?

Answer 8

When you are contracting and exhaling, the diaphragm relaxes and domes and moves upwards which effectively makes the chest cavity smaller. This increases the air pressure in the chest cavity, which in turn causes air to be pushed out of the lungs.

Question 9

What is a spirometer trace?

Answer 9

Spirometer Trace- is a measure of lung volumes.

Question 10

What does tidal volume mean?

Answer 10

Tidal Volume- The volume of air inspired or expired/ exchanged in each breath

Question 11

What does Inspiratory reserve volume mean?

Answer 11

Inspiratory reserve Volume- The amount of air that could be breathed out after tidal volume.

Question 12

What does expiratory reserve volume mean?

Answer 12

Expiratory reserve Volume- The amount of air that could be breathed out after tidal volume.

Question 13

What does residual volume mean?

Answer 13

Residual Volume- The amount of air left in the lungs after maximal expiration.

Question 14

What does Cardio Cycle mean?

Answer 14

Cardio Cycle- The process of the heart going through the stages of systole and diastole in the atria and ventricles.

Question 15

What does diastolic blood pressure mean?

Answer 15

Diastolic Blood Pressure- When the heart is relaxing

Question 16

What does Embolism mean?

Answer 16

Embolism- The blockage of a blood vessel

Question 17

What does haemoglobin mean?

Answer 17

Haemoglobin- The substance in red blood cells which transport oxygen (as oxyhaemoglobin) and carbon dioxide.

Question 18

What does Hypertension mean?

Answer 18

Hypertension- High blood pressure in the arteries.

Question 19

What does Systolic Blood Pressure mean?

Answer 19

Systolic blood Pressure- When the heart is contracting.

Question 20

What does Vasoconstriction mean?

Answer 20

Vasoconstriction- Narrowing of the internal diameter of a blood vessel to decrease blood flow.

Question 21

What does Vasodilation?

Answer 21

Vasodilation- Widening of the internal diameter of a blood vessel to increase blood flow.

Question 22

Explain the pathway of blood in 5 stages.

Answer 22

1) The oxygenated blood enters the right atrium. At this time it is dark red with little oxygen but mainly waste products e.g CO2.
2) The right atrium pumps the blood into the right ventricle through the bicuspid valve
3) The right ventricle pumps the blood through the pulmonary artery tot he lungs, where O2 is picked up, and CO2 is deposited. It is at this time that the blood changes colour to bright red because of he O2 it has collected.
4) From the lungs the blood returns to the left atrium through the pulmonary vein.
5) The left atrium pumps the blood into the left ventricle and the blood leaves here though the aorta to be distributed to the reds of the body.

Question 23

What are the 3 types of blood vessels in the body?

Answer 23

• Arteries
• Veins
• Capillaries

Question 24

Name 5 characteristics of arteries.

Answer 24

• Thick walls
• carry oxygenated blood at high pressure away from heart
• No valves
• More elastic walls then the veins
• They sub-dived into smaller vessels known as arterioles.

Question 25

Name 4 characteristics of veins.

Answer 25

• carry deoxygenated blood back tot he heart
• Thinner walls than arteries
• Less elastic walls than arteries
• Has valves to ensure the blood doesn’t back flow

Question 26

Name 3 characteristics of capillaries.

Answer 26

• Microscopic vessels
• Allow CO2 and O2 and waste products to pass through their walls
• Have very thin walls

Question 27

What is the equation for Cardiac output?

Answer 27

Cardiac Output = Stroke volume x Heart rate