Answer:
A. anaerobic respiration in muscle cells, forming lactic acid
Explanation:
Running marathon is a vigorous exercise, which often leads to excessive use of oxygen in the cells of the athlete. This causes the cells to switch from the aerobic (with oxygen) to the anaerobic (without oxygen) mode of respiration. This anaerobic respiration produces a product called LACTATE OR LACTIC ACID.
The lactic acid becomes excessive and gets stored in the muscle cells of the athlete. This often leads to cramps, muscle pulls etc. during the marathon. Therefore, an individual running a marathon may experience periods of oxygen deprivation that can lead to anaerobic respiration in muscle cells, forming lactic acid.
Answer:
Carcinogenic
Explanation:
A carcinogenic substance is able to modify or damage the genome in a way which promotes the formation of cancerous cells. Cell cycle checkpoint proteins are very crucial for the progression of normal cell cycle. They check for any anomaly in their designated step and halt the process if it is detected. Repair mechanism is activated and cell cycle does not progress till the damage has been repaired.
Here, the pollutant alters the structure of these proteins such that they lose their function. They are not be able to stop cell cycle from progressing even if there is some damage in the genome. The cell divides and gives rise to more damaged cells. Eventually these cells lose their normal function and just keep dividing due to which their division rate becomes double of the normal rate. It can ultimately give rise to cancer which is why the chemical is carcinogenic.
Water conservation involves protecting the animals
