Globin 1 and globin 2 genes of insects are understood to have diverged approximately 170 million years ago, through duplication, from a common globin gene ancestor. The two genes that code for haemoglobin have conserved regions; oxygen-binding and heme- regions. Globin 2 gene has lost the intron region that is still present in the globin 1 gene. The percentage divergence is 7.2% with 20 varying nucleotides.
<span>Forebrain. Forebrain is related to functions of cognitive activities. It is part of brain with other two parts which are hind brain and mid brain. Amygdala related to emotions. Midbrain related to vision, hearing etc. while hindbrain is concerned with control involuntry functions like respiration.</span>
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.
An action potential will not occur unless the membrane potential AT THE VOLTAGE GATED SODIUM CHANNEL reaches a level called THRESHOLD.
An action potential refers to the change in the electrical potential which occurs as a result of the passage of impulses along the membrane of muscle cells or nerve cells. An action potential occurs when there is depolarization of the cell membrane to the threshold stage.
The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being bent (refracted) by the liquid core.