Biology 9700/13 May June 2011 | Cambridge AS Level Past Papers With Mark Scheme

1. Water transport in plants: roles of cohesion, adhesion, and osmosis; xerophytic adaptations reducing water loss, such as rolled leaves and sunken stomata.

2. Vascular system: artery vs. vein structures under light microscopy; water potential gradients in plant vascular tissues influencing fluid movement.

3. Enzymatic processes: competitive vs. non-competitive inhibition; effects on active site conformation and reaction rates; protein structures determining enzyme specificity.

4. Microscopy: resolution and magnification differences in light and electron microscopes; visible cellular structures at ×400 magnification.

5. Photosynthesis and nitrogen cycling: energy use in grasslands for growth and respiration; nitrogen availability processes excluding denitrification.

6. Cardiovascular and respiratory systems: gas exchange efficiency in alveoli, adaptations in tissue fluid composition, and effects of emphysema and smoking cessation.

7. Genetic engineering and inheritance: DNA replication inhibition mechanisms by drugs, transcription steps in gene expression, and disease transmission likelihoods like sickle cell anemia vs. cholera.

8. Antibiotic resistance: data analysis on bacterial zone inhibition, testing antibiotic effectiveness, and trends in bacterial resistance over time.