Answer:
The ovarian cycle regulates endocrine tissue preparation, and egg release in female body.
The first half of the ovarian cycle as the follicular process. Slowly growing rates of FSH and LH are causing follicle development on the ovary surface. This cycle makes the egg primed for ovulation. As the follicles develop they start releasing estrogens and low progesterone levels. Progesterone locks the endometrium in order to help ensure pregnancy. It takes about seven days to travel ovum through the Fallopian tube and to get implanted in uterus. There are 30-60 cells at this point of evolution, called the morula. If there is no pregnancy implantation the lining would be sloughed off. estrogen levels increase after around 5 days, and the menstrual cycle enters the proliferative process. The endometrium starts to regrow, replacing the weakening blood vessels and glands at the end of the last cycle.
Answer:
A XY or XY gamete fuses with a normal gamete (X or Y)
Explanation:
Meiotic nondisjunction is the phenomenon whereby chromosomes fail to separate during meiosis I or II. Meiotic nondisjunction leads to the formation of abnormal gametes I.e. gametes with additional or missing chromosomal piece.
The fusion of these abnormal gametes produced by nondisijuction with a normal gamete (X or Y chromosome). This leads to a condition called ANEUPLOIDY, which is a chromosomal disorder. In the case od Calix, XXY is an ANEUPLOIDY state that could have resulted because there was a fusion between a XX gamete and Y gamete or XY and X. The XY or XX gametes are produced as a result of nondisijuction.
They are all made of eukaryotic cells and have a nuclei
Answer:
Yes...This is an example of speciation by natural selection
Explanation:
As we know that natural selection always promote those evolutionary changes that are necessary. Changes that happen in chromosome number always promote with a specie that is closely related to the parent specie and produce fertile off-springs. These new generations are most adaptable and can survive in the environment more efficiently than the previous ones.
Additionally, other than natural selection, speciation can also happen as a result of random mutations, genetic drift and by means of artificial selection as well. But the natural likelihood of all these is probably low as compared to that of natural selection.
Answer:
There is consistency of the current study's findings with that found in previous research studies.