AQA Biology Unit 1 Lungs and Immunity

?
What are the symptoms of pulmonary fibrosis?
1) Persistent cough 2) tiredness and loss of appetite 3) Weight loss 4)Coughing up blood can occur
1 of 32
How is TB spread?
Droplet infection (and through drinking milk containing the bacterium)
2 of 32
Who are the people at greater risk of contracting TB?
1) In close prolonged contact with someone infected 2) Work in facilities with lots of people living close 3) From countries where TB is common 4) Have reduced immunity
3 of 32
What is the course of the TB infection? (card 1)
1) Bacteria grow and divide in upper lungs due to high oxygen supply 2) Immune response and white blood cells accumulate at infection site (ingest bacteria) 3) Inflammation of lymph nodes - called primary infection 4) Few symptoms present
4 of 32
What is the course of the TB infection? (card 2)
5) Years later bacteria may emerge - post-primary TB occurs 6) Infection also arises in upper regions, bacteria destroy the lung tissue causing cavities and scar tissues 7) Coughing up lung tissues occurs - if not treated can spread and can kill
5 of 32
What is pulmonary fibrosis?
When scar tissue forms on epithelium of lungs causing them to be irreversibly thickened
6 of 32
How does pulmonary fibrosis decrease oxygen content in the blood?
1) increased diffusion pathway 2) Volume of air the lungs can contain has been reduced 3) Fibrosis also reduced elasticity of the lungs - less ventilation of air
7 of 32
What are the symptoms of pulmonary fibrosis?
1) Shortness of breath - lower volume of air, less oxygen inspired, increased diffusion pathwathway 2) Chronic dry cough - obstruction in airway occurs (cant be removed) 3) Pain in chest 4) Weakness - reduced oxygen in blood means less cell resp.
8 of 32
What is asthma?
It is a localised allergic reaction to an allergen such as pollen - histamine is released
9 of 32
What effects does the release of histamine have?
1) Lining of airway becomes inflamed 2) Cells of epithelium lining secrete larger quantities of mucus 3) Fluid leaves the capillaries and enters airways 4) The surrounding muscles contract narrowing the airway of the bronchioles
10 of 32
What are the symptoms of asthma?
1) Difficulty in breathing - constriction of bronchioles and extra fluid 2) A wheezing sound - air passing through a narrowed bronchi/bronchioles 3) A tightness in chest - not being able to ventilate lungs 4) Coughing - reflex to narrowed airway
11 of 32
What is emphysema?
Where the elastin in the lungs becomes permanently stretched out and hence cannot fully vent the lungs
12 of 32
What are the symptoms of emphysema?
1) Shortness of breath - less venting, smaller surface area of alveoli, increased resp rate as a result 2) Chronic cough - attempt to remove damaged tissues and mucus as cilia have been destroyed 3) Bluish skin colour -low levels of oxygen in blood
13 of 32
What is an atheroma?
A fatty deposit forming on the artery wall, build up of fatty LDL's, streaks enlarge to atheromatous plaque, bulge into lumen causing narrowing of the lumen
14 of 32
What is a thrombosis? (what is the preliminary cause - atheroma)
Where a rough surface on blood vessel interrupts smooth blood flow - this can form blood clots which blocks the blood vessels, prevents blood flow which causes muscles after the clot to die as lack of oxygen and glucose - can occur in coronary artery
15 of 32
What is an aneurysm?
Where and atheroma weakens the artery walls - weaken points swell to form a balloon-like blood filled structure. Can burst forming a haemorrhage or CVA
16 of 32
What are the two types of defence mechanisms?
1) Non-Specific (phagocytosis + skin) 2) Specific (cell-mediated with T lumphocyte + Humoral responses involving B lymphocytes)
17 of 32
What are the three barriers to entry?
1) Protective covering 2) Epithelia covered in mucus 3) HCl in the stomach acid
18 of 32
Explain the process of phagocytosis?
1) Phagocytes move towards the pathogen 2) Phagocytes attach to surface of pathogen 3) Phagocyte engulf pathogen placing them in a phagosome 4) Lysosomes move towards pathogen 5) Lytic enzymes break pathogen down 6) Soluble products are absorbed
19 of 32
What is an antigen?
It is a small protein marker which triggers an immune response
20 of 32
What immune response do B cells have?
B cells are associated with humoral immunity (involving antibodies in the body fluid)
21 of 32
What immune response do T cells have?
They are cell-mediated immunity
22 of 32
Where are B and T cells developed and matured?
B in bone marrow. T in thymus gland
23 of 32
Explain cell-mediated immunity? (card 1)
T lymphocytes respond to cells which have been invaded by non-self material as antigen-presenting cells put antigens on cell-surface membrane. Phagocyte puts antigen on surface, complementry T helper cells bind with antigens which activates other
24 of 32
Explain cell-mediated immunity? (card 2)
T cells to start dividing by mitosis forming clones.
25 of 32
What 4 things can cloned T cells do?
1) Develop memory cells 2) Stimulate phagocytes to engulf pathogens (phagocytosis) 3) Stimulate B cells to divide 4) Kill infected cells
26 of 32
How do T cells kill infected cells?
They produce a protein which makes a hole in the cell-surface membrane, meaning that it becomes freely permeable
27 of 32
What does humoral immunity involve?
Antibodies
28 of 32
Explain the process of B cells in humoral immunity? (card 1)
1) Antigen of invading pathogen is taken up by B cells and placed on the surface 2) T helper cells attach to the processed antigen on the B cells hence activating them 3) B cells are activated and can now divide by mitosis to give a clone of plasma
29 of 32
Explain the process of B cells in humoral immunity? (card 2)
4) The cloned plasma cells produce antibodies which are complementry to the antigen 5) Antibodies attach forming antigen-antibody complexes and destroy - this is called the primary immune response 6) Some B cells develop into memory cells
30 of 32
What is the purpose of memory cells?
To allow a faster secondary immune response if the antigen is recognised again
31 of 32
What are the two parts of an antigen?
1) Variable region 2) Constant region
32 of 32

Other cards in this set

Card 2

Front

How is TB spread?

Back

Droplet infection (and through drinking milk containing the bacterium)

Card 3

Front

Who are the people at greater risk of contracting TB?

Back

Preview of the front of card 3

Card 4

Front

What is the course of the TB infection? (card 1)

Back

Preview of the front of card 4

Card 5

Front

What is the course of the TB infection? (card 2)

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Health, illness and disease resources »