Respiration 1: The lung

Question 1

What is the overview pathway of the respiration system from nasal cavity

Answer 1

Into the nasal cavity, pharnyx, Larynx, Trachea and then in to left and right bronchi into lots of tubes called bronchioles and then to the respiratory bronchioles, alveolar ducts + sacs and then alveoli.

Question 2

What is the overall definition of respiration and the 3 places it takes place

Answer 2

Respiration is a general term for the transfer of gas (CO2 and O2) across a boundary/membrane/somewhere different.
3 places is external, internal and cellular

Question 3

Compare the 3 places that respiration takes place

Answer 3

External: transfer of gases from external atmosphere to blood through pulmonary capillaries

Internal: transfer of gases from blood to tissues and interstitial fluid via systemic capillaries

Cellular : where O2 is consumed and Co2 is produced

Question 4

What is Pulmonary Ventilation. How does it relate to ventilatory pump

Answer 4

The mechanical bulk movement of air in and out of the lungs. It uses the ventilatory pump= rib cage, associated muscles and diaphragm

Question 5

Compare the two functional classifications of the Respiratory system. What are they

Answer 5

Conducting zone: series of cavities, thick walled tubes that conduct air from the nasal cavity to the bronchioles. It warms, cleans and humidifies the air

The respiratory zone: is the tiny thinwalled airways where gas exchange occurs. (respiratory bronchioles -> alveoli)

Question 6

• Upper vs lower RTract:
  Where is a blockage of the respiratory tract worse.
  Where is an infection worse

Answer 6

A blockage is worse in the upper conducting pathway because there are more branches in the lower tract.
Whereas an infection is better in the upper tract because the respiratory zone is much closer with blood supply and therefore can grow more easily/ get into the blood.

Question 7

What are the anatomical/structural classification of the respiratory system.

Answer 7

Upper Respiratory tract : Nose ->larynx

Lower Respiratory tract: Trachea- alveoli

Question 8

What is the three ‘stops’ where oxygen bus goes from outside to inside the body and CO2 goes from inside to outside

Answer 8

First stop - ventilatory pump as air
2nd stop- Left cardiac pump (in blood)
3rd stop- Cells in tissue where CO2 is produced.
Co2 then goes to Right cardiac pump and then back to the ventilatory pump

Question 9

What is the overall purpose of the nasal cavity

Answer 9

Prepares the air for gas exchange by making it

1. Warm the air to 37’
2. Clean - filtering
3. Wet - humidify (100% saturated)

Question 10

What features of the nasal cavity help to filter the air

Answer 10

• Vibrissae -coarse hairs filter big particles
• Respiratory epithelium mucous
• Seromucus gland close to the entrance of nose

Question 11

What features of the nasal cavity help to humidify the air

Answer 11

• Respiratory epithelium mucous helps to transfer moisture to dry air
• Seromucus gland close to the entrance of nose

Question 12

What features of the nasal cavity help to warm the air

Answer 12

• Rich blood supply underneath the epithelium that is vasodilated and close to the surface to allow heat exchange

Question 13

What are Turbinates (bones) structure and function

Answer 13

3 conchae of the lateral nasal cavity wall (sup, mid, inf) that increase the SA of the nasal cavity. It slows the air and causes turbulence. This allows the air to slow down for filtering, warming and humidifying.

Question 14

What is the movement of mucocillary escalator in the respiratory epithelium - where is it moving things

Answer 14

The cillia move the mucus layer on top in a concerted mexican wave towards the throat

Question 15

What is the structure and function of the paranasal sinuses

Answer 15

They are cavities behind the lateral nasal cavity walls connected by little holes make your head light and provide a resonance and tone to your voice.

Question 16

What are the 3 parts of the pharynx and what is the difference between then

Answer 16

1. Nasopharynx which connects the Nasal cavity.
2. Oropharynx that connects the oral cavity
3. Laryngopharynx that connects the larynx and throat.

Question 17

How is food kept out of the airway

Answer 17

When we swallow, the nasopharynx is closed by the soft palate which pushes the food down into the posterior eosophagus. The bolus of food passively pushes the epiglottis, a flap of elastic cartilage covered in epithelium closed over the air way. Then springs back after food gone

Question 18

What are the generations of branches of bronchi that are part of the conducting zone

Answer 18

1. Main stem bronchi
2. Lobar bronchi
3. Segmental bronchi
   4-9 Smaller bronchi
   10-15 Bronchioles
   16-19 Terminal bronchioles

Question 19

What are the generations of branches of bronchi that are part of the respiratory zone

Answer 19

20-23 Respiratory bronchi (where air is clean)
24-27 Alveolar ducts
28 Alveolar sacs

Question 20

Describe the main features of the Trachea:

Answer 20

Its tube as thick as your thumb anterior to the chest. It has a stiff C shaped rings of cartilage with the posterior ends connected by trachealis muscle.
It is lined with the respiratory epithelium that has mucocilary escalator towards the nasopharynx.

Question 21

Where does the oesophagus sit in relation to the traches

Answer 21

It is dorsal to the trachea lying on the trachealis.