Something in nature that people use is a natural resource.
C. Microscope
They were able to get magnification like never before
B. Phylogeny. Phylogeny has a similar meaning to evolutionary being a synonym<span />
<u>Answer:</u>
<em>An LH spike occurs during oestrogen feedback loop because the pituitary gland positively responds to the high level of oestrogen </em>and produces more LH.
During the ovulatory phase the amount of hormones like oestrogen, follicle stimulating hormone and Leutenising hormone are high. <em>FSH enables the formation of follicles and LH enables the rupture of matured follicle and release of ovum into the oviduct. </em>
In the middle of menstrual cycle when the amount of oestrogen is high pituitary gland give <em>a positive feedback by producing more LH.</em>
<em>This is called LH surge.</em> By this time primary follicles would have matured into graffian follicle and would be holding the ovum. <em>LH surge causes the follicle to rupture and the ovum gets released into the oviduct. </em>
A somatic cell is a cell that is any of the 22 chromosome pairs that aren’t reproductive cells. So, these cells would have the full 26 chromosomes that a frog usually has.
However, since an egg cell is a reproductive cell and needs to combine with another reproductive cell to create one whole combined cell and organism, it would only have 13 chromosomes. The egg cell is like half of a somatic cell, so it will have half of however many the somatic cell will have.