respiratory system

Question 1

what are the functions of the respiratory system?

Answer 1

• Deliver oxygen from the atmosphere to the lungs
• Provide method of gaseous exchange within the lungs
• Create speech as air passes over the vocal cords
• Facilitate sense of smell
• Expel heat and water vapor in the air breathed out

Question 2

what are the 3 main sections of the respiratory system?

Answer 2

• Air passages
• Lungs
• Diaphragm

Question 3

what is the alveoli?

Answer 3

• Cup shaped sacs found at the end of bronchioles
• Surrounded by capillaries, site for the continual exchange of 02 and CO2
• process of diffusion – the movement of gas from an area of high concentration to low concentration

Question 4

what are the lungs?

Answer 4

• Located within the thoracic cavity and protected by the sternum, ribs and vertebral column
• They contain the bronchi, bronchioles and alveoli
• Gas exchange occurs at the site of the alveoli

Question 5

what is diffusion?

Answer 5

the movement of substances from a high to low concentration through a semi-permeable membrane

Question 6

where are the two sites of diffusion within the body?

Answer 6

lungs (alveoli) and muscles

Question 7

what are the features of the alveoli that allow efficient gas exchange to occur?

Answer 7

• Large surface area to volume ratio
• Surrounded by capillaries
• Very thin walls

Question 8

what is the diaphragm?

Answer 8

• Involuntary or smooth muscle that contracts and relaxes to aid breathing at all times

Question 9

what is ventilation?

Answer 9

The amount of air that is inspired and expired during 1 minute’
= tidal volume x respiratory rate

Question 10

what is tidal volume?

Answer 10

The amount of air breathed in and out in 1 breath

Question 11

what is respiratory rate?

Answer 11

The number of breaths per minute

Question 12

what happens during inspiration?

Answer 12

• Volume of lungs increases
• External intercostal muscles contract
• internal intercostal muscles relax
• lift rib cage up
• diaphragm contracts to become flatter
• area of low pressure
• Air enters the lungs moving from area of high pressure to low pressure

Question 13

what happens during expiration?

Answer 13

• Volume of lungs decreases
• External intercostal muscles relax
• internal intercostal muscles contract
• lower rib cage
• diaphragm relaxes to become dome-shaped
• high pressure
• Air exits the lungs from an area of high pressure to low.

Question 14

describe the process of gaseous exchange in the lungs

Answer 14

• oxygen moves from the alveoli of the lungs into the capillaries which surround them. carbon dioxide moves from the capillaries into the alveoli to be expired.
• oxygen moves from a high concentration in the alveoli to the capillaries where they are of low concentration.

Question 15

what features allow for effective gaseous exchange?

Answer 15

• Large surface area to volume ratio - so lots of opportunity for gas exchange to occur
• Surrounded by capillaries – to allow for gas exchange to occur efficiently into the blood
• Very thin walls – to promote diffusion of gases

Question 16

describe the process of gaseous exchange within muscles

Answer 16

• allow the transport of oxygen to muscle tissue and carbon dioxide (a by-product) to be removed.
• oxygen is of a high concentration in the capillaries so moves to the muscle tissue where it is of low concentration.