2010 Unit 1 Jan Flashcards
Use your knowledge of water potential to explain why these adults get diarrhoea when they drink milk.
- Low(er) water potential in lumen / intestine / gut;
* Water enters lumen / leaves (body) cells / by osmosis
Describe the path by which oxygen goes from an alveolus to the blood.
- Through alveolar epithelium;
* Through capillary epithelium/endothelium;
Explain why people with miner’s lung have a lower concentration of oxygen in their blood.
- (Thicker alveolar wall)
* (So) Longer diffusion pathway / slower diffusion;
Describe how ventilation helps to maintain difference in alvelous and lungs oxygen concentration.
(In alveolus)
• Brings in air containing a high(er) oxygen concentration;
• Removes air with a low(er) oxygen concentration;
Give one other way that helps to maintain the difference in oxygen concentration.
• Circulation of blood / moving blood;
Explain how the drug lowers the rate of reaction controlled by folate reductase.
• drug is a similar shape / structure to
substrate;
• Binds to / fits / is complementary to active site;
• Less enzyme-substrate complexes formed;
Explain how mitochondria help the cell to absorb the products of digestion.
• (Site of aerobic) respiration / ATP production / energy
release;
• For active transport
The students were advised that they could improve the reliability of their results
by taking additional readings at the same concentrations of sodium chloride.
Explain how.
(Allows)
• Anomalies to be identified / effect of anomalies to be
reduced / effect of variation in data to be minimised;
• A mean to be calculated;
The students used a graph of their results to find the sodium chloride solution
with the same water potential as the apple tissue. Describe how they did this.
• Plot (sodium chloride) concentration against ratio / draw line of best
• Find (sodium chloride concentration from the graph)
where the ratio is 1 / there is no change in mass;
Describe what the graph shows about the effect of substrate concentration on the
rate of this enzyme-controlled reaction.
Increases then plateaus
What limits the rate of this reaction between points A and B?
Substrate concentration
As substrate concentration increases, rate increases
What is the advantage of giving results as a ratio
Allows comparison
The idea that discs had different starting masses
Graph could be improved by taking additional readings
Line of best fit/curve more precise
Can plot SDvalues/ error bars
To show how spread out the results are
Explain why antibodies are referred to as monoclonal
Antibodies produced from same B cell/ plasma cell
Protiens are specific why?
Specific primary structure
Specific tertiary structure
complementarty to one antigen
A test using
monoclonal antibodies allows vets to identify cattle that are carriers.
The tests using monoclonal antibodies allow vets to identify brucellosis while they are
still on a farm. Explain the advantages of this
Can isolate infected cattle
Reduced spread of disease
Do not need to kill cattle
Infected products not sold
The cardiac cycle is controlled by the sinoatrial node (SAN) and the atrioventricular
node (AVN). Describe how.
SAN initiates heartbeat
(SAN) sends wave of electrical activity (across atria) causing atrial contraction
AVN delays (electrical activity
Allowing ventricle to fill with blood before they contract
(AVN) sends wave of electrical activity
down Bundle of His / Purkyne fibres
Causing ventricular systole
What is atheroma and how may it cause myocardial infarction?
Cholesterol / plaque cells; 2. In artery wall 3. Atheroma linked to blood clot 4. (Blocks) coronary artery Reduces oxygen (to heart muscle Heart muscle unable to respire
