Hydrophilic heads, hyrdophobic tails. Heads are made of phosphate and the tails are made of lipids.
Answer:
C. Axis
Explanation:
The label "N" refers to the northern hemisphere, and the red line is the axis on which the Earth rotates.
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.
It is thought that life arose on earth around four billion years ago. The endosymbiotic theory states that some of the organelles in today's eukaryotic cells were once prokaryotic microbes.
The gaps (approximately 1 micrometer wide) formed between myelin sheath cells long the axons are called Nodes of Ranvier. Since fat serves as a good insulator, the myelin sheaths speed the rate of transmission of an electrical impulse along the axon.
