Biology Flashcards
(10 cards)
What happens to enzyme activity as temperature increases?
As temperature increases, enzyme activity increases due to more frequent collisions. At optimum temperature, the reaction occurs. However, enzymes denature and active sites change at high temperatures, causing enzyme activity to fall sharply.
How would you investigate the effect of pH on the activity of amylase?
- Add starch solution to different tubes.
- Add amylase enzyme and different pH buffers to each tube.
- Place in water bath at 37°C.
- Take samples at intervals.
- Record time when iodine stops turning blue-black (starch fully broken down).
- Repeat and calculate results.
What is the difference between diffusion and active transport?
Diffusion moves substances from high to low concentration without needing energy, while active transport moves substances from low to high concentration using energy.
How does oxygen move in the body?
Oxygen moves from the alveoli into the blood by diffusion from high concentration in the alveoli to lower concentration in blood capillaries.
What is the word and symbol equation for photosynthesis?
Word: Carbon dioxide+ water-> oxygen+ glucose
Symbol: 6CO2 + 6H2O -> C6H12O6 + 6O2.
Describe an experiment to investigate the effect of light intensity on the rate of photosynthesis.
- Place pondweed in water with sodium hydrogen carbonate.
- Place a lamp at a set distance.
- Measure bubbles released in a minute using a gas syringe.
- Repeat at different distances.
- Keep other variables constant.
- Repeat and calculate results.
Identify one control variable in an investigation.
Control variable could be light intensity or pH, depending on the investigation.
Suggest one improvement for an experiment.
Repeat the experiment and calculate a mean to improve accuracy.
How do vaccines work?
Vaccines stimulate the immune system to allow faster responses to infections.
Why do antibiotics not kill viruses?
Viruses live inside body cells. Antibiotics cannot target viruses without harming body cells.
