Lower and Upper Respiratory Anatomy and Physiology

Question 1

Describe the location and anatomy of the lungs

Answer 1

• The Concave base of the lungs rests on the diaphragm
• The Apex of the lung is superior, and extends slightly above the clavicles
• The trachea is an airway that branches to form a tree like formation of bronchi and bronchioles.
  -The right lung has three lobes and the left lung has two lobes

Question 2

Identify SIX functions of the Respiratory System

Answer 2

1. Supplies oxygen and removes carbon dioxide
2. Filters, warms and humifies air
3. Regulation of pH
4. Olfaction
5. Voice Production
6. Respiratory pump for venous and lymph return

Question 3

Identify the THREE parts of the Pharynx AND state the function for each

Answer 3

Nasopharynx - connect your nasal passages to the rest of your respiratory system.
Oropharynx - Passage for food and air
Laryngopharynx - Passage for food and air

Question 4

Identify at least FOUR functions of the larynx

Answer 4

1. Passage for air
2. Epiglottis - switching mechanism to prevent food/drink entering the larynx during swallowing
3. Contains vocal folds (glottis) to produce sound
   4.Initiates cough reflex

Question 5

Discuss the effects of homeostatic imbalance in the Upper Respiratory Tract: Viral & Bacterial infections

Answer 5

• Inflammation of nasal cavity mucus membranes
• Excess mucus production
• Nasal congestion
• Postnasal drip

Question 6

Describe sinuses

Answer 6

Paranasal sinuses contain certain cavities in cranial and facial bones lined with respiratory mucosa and serve to lighten the skull and drain into the nasal cavity, act as a resonating chamber for speech.

Question 7

Describe the structure and functions of the nasal cavity

Answer 7

Lined by mucus membranes - produces copious amounts of mucus
- Contains lysozyme to destroy bacteria
- Traps dust, bacteria and debris
- High water content humidifies incoming air

Ciliated cells - create gentle current to move mucus posteriorly towards pharynx for swallowing

Sensory nerve ending - stimulate sneezing when irritated

Rich blood supply and thin wall - warm incoming air

Question 8

Describe the protective mechanisms of cilia

Answer 8

propel debris-laden mucus toward the pharynx

Question 9

Describe the protective mechanisms of cartilage rings

Answer 9

stops the trachea from collapsing and shutting off, also allow the oesophagus to expand when food moves down during swallowing

Question 10

Describe the protective mechanisms of carina

Answer 10

branch point of the trachea into the bronchi) is extremely sensitive and violent coughing is triggered when a foreign object touches it.

Question 11

State the location of origin for a cough and what causes a cough

Answer 11

The mucosa at the carina (branch point of the trachea into the bronchi) is extremely sensitive and violent coughing is triggered when a foreign object touches it.

Question 12

State the effects of Sympathetic AND Parasympathetic stimulation on the bronchioles

Answer 12

Sympathetic stimulation - causes bronchodilation by relaxing smooth muscle enabling more air in through a larger airway, During exercise SNS activity increases, adrenaline release is increased and lung ventilation improves.

Parasympathetic stimulation causes bronchoconstriction reducing airflow when resting or due to histamine during allergic reactions.

Question 13

Describe the structure AND function of the alveoli

Answer 13

Lined with simple squamous epithelium to optimise diffusion, alveolar macrophages remove particles from alveoli, alveoli are the main gas exchange structure of the respiratory tract.

Question 14

Describe the TWO pleural membranes AND their function

Answer 14

Visceral pleural - covers the lungs
Partial pleural - lines the wall of the thoracic cavity

Function: as the pleura adheres to the chest wall and to the lung it produces a mechanical coupling for the two layers to move together lifting up the lung during inspiration and allow it to fall during exhalation.

Question 15

Describe the function of surfactant in relation to surface tension

Answer 15

Prevents a thin watery liquid film lining the surface of alveoli exerting a force called surface tension.
If the film was pure water surface tension would make the alveoli collapse inwards between breaths, the film also contains surfactant.

Question 16

Define surfactant

Answer 16

a detergent-like complex of lipids and proteins which reduces surface tension, prevents the alveoli from collapsing, reduces the energy needed to expand the lungs during each inspiration (increases compliance)

Question 17

Identify the effects of Asthma in the respiratory tract

Answer 17

Bronchioles are narrowed by asthma. Triggered by an allergen or other factors which causes smooth muscle spasm, excessive mucous production, swelling and inflammation and may result in an audible wheeze.