Answer:
Atmospheric oxygen is too reactive
Explanation:
the correct answer is Evaporation
hope this helps :)
The correct answer is option A. They either match up with a receptor molecule on the surface of the cell or enter the cell through the membrane.
The intercellular signals are the signals, which transfer the signals from one cell to the another and the intracellular signals are those signals, which carries message within the cell.
The intercellular signals may or may not be transferred through the gap junctions. The chemical signals are one of the type of the cell signals. The chemical signalling molecules generally have a receptor on the cells, where these molecules can bind and can be cause the activation of the cell. The chemical signals can also enter into the cells through active transport and facilitated diffusion. So, these type of transports does not go through the Gap junction.
B. Mitochondria
The process of cellular respiration is essentially when oxygen and carbon transfuse themselves together to create carb on dioxide, which in turns creates energy.
The entire process is formed in the powerhouse of the cell, or in other words, the mitochondria.
A part of this question that may have been confusing is the answer, "lungs". Since respiration is correlated to the lungs, you may have been confused. However, this is a process that occurs within your cells, so on a small scale than your entire body.
Answer:
faced a struggle for survival
Explanation:
The woolly mammoths became extinct, unlike the other species, because the woolly mammoths faced a struggle for survival due to changing of environmental conditions. Global warming is the main cause of extinction of woolly mammoth which destroy their habitats about 10,500 years ago. The environmental conditions are not favourable for them so they faced struggle for survival which causes extinction of woolly mammoth.
