Answer:
a. air from entering the body of the flask
Answer:
Pros of HeLa cells:
- HeLa cells are immortal ,easy to maintain and can be kept alive.
- HeLa cells easily contaminate cell lines and thus can be incorporated easily into target tissues.
Cons of HeLa cell:
- The HeLa cells can easily contaminate cell lines and a lack of regular monitoring leads to unwanted contamination of cell lines resulting in wastage.
Explanation:
HeLa cells are immortal cells that are used in scientific and medical research. These were obtained from Henrietta Lacks , a cervical cancer patient. These cells are well known for their immortality, rapid growth and high contamination rate. These were unique cancerous cells that kept on dividing and remained alive easily.
Answer:
Option (1).
Explanation:
Action potential may be defined as the change in the cell potential that helps in the transmission of the nerve impulse. The resting membrane potential of the cell is -70mV.
The depolarization phase of the cell has membrane potential towards more positive. After the depolarization phase, the sodium channels are closed and potassium influx occurs that causes the re-polarization of the cell. This activity of the re-polarization is not the consequence of the closing of the inactivation gates.
Thus, the correct answer is option (1).
The effect of a catalyst is to increase the speed of the reaction, this is the speed at which reactants, A and B, are consumed, ant the product, C, is produced.
Given that when C is produced the solution bubbles, the bubbles are an indication of progression of the reaction.
The greater the speed of reaction, the earlier the reaction will end and the earlier the bubbles will stop.
So the student can identify the catalyst because the bubbles will stop first.
Answer: <span>The test tube that stops bubbling first contains the catalyst.</span>