Biology 4BI1/2BR May June 2020

Edexcel IGCSE Biology (4BI1) Nov 2020

معلم موافق رایگان بودن است.

1. Artificial Insemination and Genetic Selection: Advantages of artificial insemination in dairy farming, semen storage in liquid nitrogen, use of sexed semen to control offspring gender, and the role of genetic selection in milk production.

2. Decomposition and Environmental Factors: Effects of temperature and leaf size on decomposition rates, impact of microorganisms on biomass breakdown, and control of biotic variables in decomposition experiments.

3. Plant Water Transport and Transpiration: Water absorption by osmosis, xylem function in water transport, impact of environmental conditions on transpiration, and adaptations reducing water loss.

4. Growth Hormones and Experimental Biology: Effect of GH on rat body mass, importance of control groups, abiotic variable control in experiments, and role of GH in transcription and protein synthesis.

5. Vaccination and Pathogen Defense: Different types of pathogens and diseases they cause, immune response to vaccination, reasons for vaccine effectiveness, and mutation effects on microbial digestion.

6. Photosynthesis and Gas Exchange: Impact of light intensity on photosynthesis, use of hydrogen-carbonate indicator for measuring CO₂, compensation point in plants, and experimental setups for studying net gas exchange.