Life Processes and Biotechnology
Life Processes and Biotechnology tests nutrition, respiration, transport, excretion and the applications of biotechnology. Expect equations, organ-function matching and examples of genetic engineering or tissue culture.
Core rules
- Photosynthesis: 6CO2 + 6H2O -> C6H12O6 + 6O2 in the presence of chlorophyll and light. It converts light energy to chemical energy.
- Aerobic respiration releases more energy than anaerobic respiration. In muscles, anaerobic respiration produces lactic acid; in yeast, it produces ethanol and carbon dioxide.
- Digestion breaks large food molecules into absorbable ones using enzymes. Xylem transports water and minerals upward; phloem transports food.
- Excretion removes metabolic wastes; nephrons in kidneys filter blood and form urine.
- Biotechnology uses living organisms or their parts. Examples include tissue culture, genetic engineering, vaccines, insulin production and Bt crops. Tissue culture uses mitosis to produce many identical plants from an explant.
Worked example
A plant carries out photosynthesis using 6 molecules of carbon dioxide. The balanced equation shows that 6 CO2 and 6 H2O produce 1 glucose and 6 O2. If 12 CO2 molecules are used, twice the reactants give 2 glucose and 12 O2. The reasoning uses the molar ratio from the balanced equation, not a guess based on mass.
Traps
Photosynthesis and respiration are not the same process. Xylem carries water, not food. Anaerobic respiration still releases energy, just less. Tissue culture produces clones, not genetically varied offspring. Biotechnology is not the same as traditional selective breeding.