structure and function of respiratory

Question 1

functions

Answer 1

• delivers oxygen from the outside to our lungs
• method of gaseous exchange within the lungs- oxygen enters the blood- carbon dioxide gets replaced
• creates speech as air passes over vocal chords
• facilitates a sense of smell
• expel heat and water vapour in carbon dioxide breathed out- by product of energy usage

Question 2

nasal cavity

Answer 2

1st
where air enters the respiratory system

Question 3

pharnyx

Answer 3

2nd
where the back of the mouth and nose meet

Question 4

larynx/ voice box

Answer 4

3rd
produces sound when air passes over it

Question 5

trachea/ windpipe

Answer 5

4th
strong piece of tissue that assists with air delivery
rings of cartilage to help stop collapsing- remain open

Question 6

bronchi

Answer 6

5th
2 tubes that provide air to our lungs

Question 7

bronchioles

Answer 7

6th
each bronchus subdivides into smaller branches

Question 8

alveoli

Answer 8

7th
- cup shaped sacs found on the end of the bronchioles
- surrounded by capillaries, they provide a site for the continual exchange of gases
- occurs through diffusion- movement of gas through capillaries

Question 9

lungs

Answer 9

• located in thoracic cavity and protected by sternum ribs and vertebrae column
• bronchi, bronchioles and alveoli
• gas exchange happens in the alveoli

Question 10

diaphragm

Answer 10

• an involuntary or smooth muscle that contracts and relaxes to help aid breathing
• as it moves up and down, the size of the cavity changes, causing breathing

Question 11

explain the process of gaseous exchange

Answer 11

• gaseous exchange is the process where oxygen is taken into the body and carbon dioxide is expelled

inhalation (breathing in)
- oxygen enters the body through the nasal cavity and mouth, it travels down the trachea (windpipe) which divides into 2 bronchi leading into each lung
- the bronchi divides into smaller tubes called bronchioles then alveoli

Diffusion in the alveoli
- the alveoli have thin walls and are surrounded by capillaries ( thin blood vessels)
- oxygen from the inhaled air diffuses through alveolar walls into the blood
- at the same time carbon dioxide from the blood diffuses into the alveoli
- oxygen

Exhalation (breathing out)
- carbon dioxide rich blood returns to the lungs
- CO2 diffuses from the blood into the alveoli then expelled from the body

Question 12

mechanisms of breathing

Answer 12

• consists of 2 principals- inhalation and exhalation
• operating on the principal that gases move from an area of high pressure to low pressure

Question 13

inhalation

Answer 13

• breathing in/ inspiration
• diaphragm contracts and becomes flatter
• external intercostal muscles contract and internal intercostal muscles relax to lift the rib cage up
• the volume of the lungs increases as the thoracic cavity expands
• air is drawn into the lungs moving from an area of high pressure to low pressure, lung pressure drops

Question 14

exhalation

Answer 14

• breathing out, expiration
• diaphragm relaxes, becomes dome shaped
• external intercostals muscles and internal intercostals muscles contract to the lower rib cage
• the volume of the lungs decreases as the pleural cavity contracts
• air exits the lungs from an area of high pressure to low, aur pressures in the lungs increases

Question 15

pathway of oxygen

Answer 15

nose/ nasal cavity/ mouth
- air enters through the nose or mouth, the nasal cavity filters dust and microbes using tiny hairs, air is warmed/ moistened for a smooth passage

pharnyx
- shared passage for food and air, epiglottis ( flap of tissue) prevents food from going into the lungs

larnyx/ voice box
- contains vocal cords

trachea/ windpipe
- tube supported by rings of cartildge to prevent, carries oxygen rich air towards the lungs

bronchi
- trachea splits into 2 lungs

bronchioles
- tiny airways that spread throughout the lungs

alveoli
- sacs that are surrounded by capillaries, oxygen diffuses across alveolur walls into blood, carbon dioxide diffuses out through alveoli to be exhaled to be exhaled

blood stream
- oxygen binds to haemoglobin, oxygen rich blood is carries to heart via pulmonary veins, the heart pumps oxygenated blood to all body tissues

capillaries
- surround alveoli, transporting oxygen into the blood

diaphragm
- muscle that helps with breathing

intercostal mucles
- part of your ribcage. linking each rib to the next