Genes and health 2:1 CF effects on lungs Flashcards
Name three genetic disorders
E.G. (and there are more…)
albinism
cystic fibrosis
Huntingdon’s disease
sickle cell anaemia
haemophilia
How do the lungs work? (4 pts)
- lungs allow rapid gas exchange (between air and blood)
- when the diaphragm is moved down and ribs move up, lung volume increases
- then air pressure in the lungs drops relative to external air pressure
- this causes air to rush = inspiration;
opposite for expiration
Which passages does air go down in to the lungs? (6pts)
The airway is composed of
- nose and/or mouth
- pharynx
- larynx
- trachea
- bronchi
- bronchioles (into the lungs)
What is the passage of air in the lungs? (2pts)
- respiratory bronchioles
- alveolar ducts
- alveolar sacs
- alveoli
Two points for bronchioles to alveoli
What is the funciton of goblet cells?
To produce mucus
Regarding the lungs, where is mucus found? (1pt)
In the tubes of the gas exchange system
What is the function of mucus in the gas exchange system in the lungs? (2pts)
1) To remove, with the help of cilia, small particles from the airways - e.g., dust, microorganisms that are inhaled
What are cilia? (1pt)
microtubule-based hair-like organelle covering epithelial cells
basically: cells with hair like structures
What is the effect of cystic fibrosis on the lungs? (5pts)
- CF sufferers have less water in the mucus produced by globulet cell so this makes the mucus sticky
- So the cilia do not ‘waft’ away debris and pathogens as easily
- oxygen also diffuses slowly through sticky mucus, which allows harmful bacteria also to flourish in anaerobic conditions
- white blood cells come to assist the fight, but they die and break down, their DNA makes the mucus even stickier
- This increases chances of lung infections
sticky mucus (lack of water) -> traps pathogens -> infection
Draw an epithelial cell; label the parts (4pts)
There are many kinds of epithelial cell, basedon their shape, but here’s a basic A-level drawing.
3 points: apical membrane or cilia, nucleus, basement membrane
Where are epithelial cells found? (3pts)
Skin surfaces of many animals
Also lining the cavities and tubes - eg, blood vessels
Cover internal organ surfaces
What do epithelium cells rest on?
A basement membrane - protein fibres in a protein-carbohydate jelly like matrix
The intestines have which kind of epithelial cells?
Columnar epithelium
How do cilia work? (1pt)
They beat in a ‘Mexican wave’ and move particles along the tube lining
What is the principle of the surface area to volume ratio?
The larger the volume, the less the ratio between the SA:VOL
EG
1x1x1 CUBE VOL:1 SA: 6 SA:VOL RATIO= 6
2x2x2 CUBE VOL: 8 SA: 24 SA:VOL RATIO= 3
4x4x4 CUBE VOL: 64 SA: 96 SA:VOL RATIO= 1.5
Sketch the structure of alveoli (5 pts)
