respiratory

Question 1

Functions of respiratory system?

Answer 1

• Gaseous exchange, oxygen from environment into blood stream, removal of carbon dioxide through expiration
• Regulate pH in blood through acid base
• Protective function of pathogens
• Voice and sound production

Question 2

upper respiratory tract

Answer 2

1. nasal cavity
2. Sinuses
3. Pharnyx

Question 3

lower respiratory tract

Answer 3

4. Larynx
5. Trachea
6. Bronchi
7. Alveoli

Question 4

Nasal cavity

Answer 4

• Site of olfactory
• Covered in Cilia and Mucus which helps to trap ducts and pathogens- protective
• Encourages reflexes such as sneezing
• warms, humidifies and filters air

Question 5

Sinuses

Answer 5

• Lighten the skull, air filled
• Protective trauma function, reduce risk of injury to eyes and brain from blunt trauma
  -Produce mucus
• Surround nasal cavity

Question 6

Pharynx

Answer 6

• Protective of lower respiratory tract
• Important in the digestive system
• Epiglottis closes when eating to prevent food from entering airway
• Nasopharynx shuts when eating

Question 7

Larynx

Answer 7

• Voice box
• Helps airflow
• The cough reflex is stimulated here by sensory receptors
• Blocks food from entering the trachea

Question 8

Trachea

Answer 8

• 20 C-shaped cartilage allows expansion of oesophagus
• Constantly open
• Surrounded by smooth muscle which allows movement of the head and neck without disturbance to trachea
• Allows you to swallow

Question 9

Bronchi

Answer 9

• Trachea splits into two branches of bronchi
• right bronchi, 3 lobes
  -left bronchi, 2 lobes, cardiac notch for heart
• further splits into bronchioles and then alveoli
• As you move down into bronchi to bronchioles and alveoli, cartilage decreases, smooth muscle increases- allows for constriction and dilation
• CLINICAL- asthma is an disease of the bronchioles as they are constricted- not possible in cartilage trachea

Question 10

Alveoli

Answer 10

• Site of gaseous exchange
• Large surface area, more space for gaseous exhange to happen
• Air filled sacs

Question 11

Gaseous exchange

Answer 11

• in alveoli
• gases must move down conc gradient
• O2: high in alveoli, low in blood, goes in blood
• Co2: high in blood, low in alveoli, goes in alveoli

Question 12

Inspiration process

Answer 12

-Active
- Diaphragm, down and flatterns
- Thoracic cavity increase in volume
- Draws air in
- External intercostal muscules contract
- Ribs and sternum out and up

Question 13

Expiration process

Answer 13

• Passive
• Diaphragm in and up
  -Throacic cavity decrease in volume
• Air exerted
• abdo muscles compress on abdo forcing diaphram down
• Ribs and sternum relax

Question 14

Oxygen dissociation curve

Answer 14

• Measures the amount of oxygen that binds with Haemoglobin
  -Y axis, sats Haemoglobin with o2
• X axis, partial pressure of 02
• Initally it is difficult for Haemoglobin to bind to 02 due to Haemoglobin having low affinity for 02.
• Shown by the increase in partial pressure, sats slowly increase
• When the first o2 binds with Haemoglobin it is alot easier for the next to bind, shown by increase in curve.
• Haemoglobin has four polypeptides, one Haemoglobin can bind with four 02
• The 4th Haem group only binds with 02 at a high partial pressure due to there being a decreased chance in o2 collision.
• n

Question 15

How is oxygen carried in blood?

Answer 15

Red blood cells- 3 adaptations
1. Biconcave, large surface area to volume ratio, allow for greater diffusion
2. Each RBC has millions of haemoglobin, helps transport oxygen
3. RBC lose its nucleus before entering circulation, more room for o2