General

General points to remember

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  • Created by: Steph
  • Created on: 21-05-13 11:42

How Science Works

Evaluation:

  • correlation, not a causation
  • other factors may be involved
  • could be due to coincidence
  • small sample size
  • no control group?
  • didn't account for all types?
  • not all people with ____ have _____

Drug testing:

  • consider possible side effects
  • consider how effective drug will be
  • dose to be given
  • cost of drug
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Lungs & Lung disease

PULMONARY VENTILATION = TIDAL VOLUME x VENTILATION RATE PER MINUTE

(how much air inhaled in 1 min) = (volume in/out in each breath) x (breaths per minute)

Tuberculosis
Transmitted in droplets, Bacteria engulfed by phagocytes & encased in tubercle, Bacteria replicate if immune system is weak, Destroy epithelial cells/alveoli, Leads to fibrosis, damage leads to less SA, so less diffusion, Damage allows bacteria to enter blood

Fibrosis/Miner's lung
Formation of scar tissue which is thicker and less elastic, Lungs less able to expand, Can't hold as much air so tidal volume is reduced and harder to expel air. Reduction of gas exchange, diffusion is slower across thicker membrane.

Asthma
Constriction of airways, air flow in and out is reduced, less oxygen enters alveoli and blood

Emphysema
Phagocytes produce enzyme that breaks down elastin, Loss of elastin, less recoil to expel air, destruction of alveoli walls reduced surface area, rate of gas exchange decreses. 


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Heart & Heart disease

CARDIAC OUTPUT = STROKE VOLUME x HEART RATE
volume pumped by heart per minute = volume in each heartbeat x number of heartbeats per min

  • Contraction = systole, Relaxation = diastole
  • left ventricle has highest pressure and thicker muscular walls so it can contract powerfully to pump blood all round body
  • right side only needs to get blood to lungs, which are nearby

ATHEROMA:
Fatty deposits build up in endothelium, partially blocks lumen of artery, restricts blood flow, < in blood pressure. Less oxygen to heart muscle, respiration & energy, no contraction

ANEURYSM:
Atheroma weakens arteries and narrow them, increases blood pressure. Blood travels through weakened artery at high pressure, push inner layers through outer layer and form aneurysm may burst

THROMBOSIS- blood clot:
Atheroma bursts through endothelium, damages wall, leaves rough ruface, platelets and fibrin form - blood clot. Complete blockage, less oxygen respiration and energy, no contraction

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How Science Works

Evaluation:

  • correlation, not a causation
  • other factors may be involved
  • could be due to coincidence
  • small sample size
  • no control group?
  • didn't account for all types?
  • not all people with ____ have _____

Drug testing:

  • consider possible side effects
  • consider how effective drug will be
  • dose to be given
  • cost of drug
4 of 4

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