The Ventilation System and COPD

Question 1

Respiratory system

Answer 1

1. pathway to alveoli: nose/mouth–> trachea–> bronchi–> bronchioles–> alveoli–> blood capillaries
2. trachea is a large membranous tube reinforced by rings of cartilage, extending from the larnyx to the bronchial tubes and conveying air to and from lungs
3. bronchi are two short branches located at the lower end of the trachea that carry air into the lungs
4. Bronchioles are airways in the lungs that lead from the bronchi to the alveoli
5. Rings of cartilage help keep trachea open for the passage of air
6. ciliated epithelial cells are cells in the trachea which have microscopic hairs( cilia) on them, which waft mucus up & out of the airways that may have trapped bacteria in
7. goblet cells are column-shaped cell found in the trachea which secretes mucus
8. bronchiole walls are composed of a relatively thick layer of smooth muscle to constrict and control airflow into alveoli.

Question 2

what are alveoli

Answer 2

small sacs found at the ends of the bronchioles. The alveoli are made from epithelial cells & are 1 cell thick. Between the alveoli there are collagen and elastic tissue. The elastic tissue will stretch during inspiration & recoil during expiration to expel air

Question 3

what are the features of alveoli that adapt them to gas exchange

Answer 3

• numerous+ highly folded so they have a large surface area for increased diffusion of gasses
• the alveolus wall is one cell thick made out of a squamous epithelium. These cells are thin & flat, meaning they provide a short diffusion distance for faster gas exchange
• vast network of blood capillaries circulation maintains a conc. gradient.

Question 4

the process of gas exchange at the alvelous

Answer 4

1. CO2 diffuses from the blood, across the smooth endothelium wall
2. across the squamous epithelium, into the alveolar air space
3. O2 diffuses from the alveolar air space, across the squamous epithelium
4. across the smooth endothelium and into the red blood cells
5. this diffusion pathway is only two cell thick

Question 5

Ventilation

Answer 5

Inspiration:
1. external intercostals contract( internal relax)
2. ribcage lifts up & out
3. Diaphragm contracts and flattens
4. Volume of thorax increases (&pressure decreases)
5. Air moves down pressure gradient into lungs
inspiration requires energy from ATP for respiration for muscle contraction
Expiration:
1. external intercostals relax ( internal contract)
2. ribcage drops down & in
3. diaphragm relaxes and lifts up
4. Volume of thorax decreases ( & pressure increases)
5. air moves down pressure gradient, out of lungs

Question 6

what is forced expiration

Answer 6

active process; uses abdominal( oblique and transverse) and internal intercostal muscles contract.

Question 7

COPD

Answer 7

1. chronic obstructive pulmonary diseases
2. smoking, pollution, chemical irritants and genetic mutation
3. history of progressive shortness of breath,excessive cough and sputum production. Patients with predominatly emphysematous COPD may have dry cough and weight loss
4. cigarette smoking, occupational chemicals and dust , air pollution, infection, heredity, aging ,asbestos

Question 8

emphysema

Answer 8

1. A lung disease marked by the loss of elasticity and thinning of the lung tissue. reduces surface area
2. shortness of breath, wheezing and increased breathing rate

Question 9

bronchitis

Answer 9

1. Any respiratory infection
2. smoking
3. air pollution
4. heavy mucous discharge,persisent cough (S)

Question 10

what is pulmonary fibrosis and asthma

Answer 10

• the formation of scar tissue in the lung, resulting in decreased lung capacity and increased difficulty in breathing. Increases diffusions pathway therefore diffusion of oxygen into blood is slower
• A chronic allergic disorder characterised by episodes of severe breathing difficulty, coughing and wheezing , becauss smooth muscle lining the bronchioles contracts and a large amount of mucus is produced ,. constriction of the airways making it diffcult to breathe. The air floe in out of the lungs is severely reduced, so less oxygen enters the alveoli