Early Child Development

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Early Child Development
There are many key factors that play up to the role of early child development, starting from before the child is nonexistent, until the child is a full grown baby.

Bodily Processes of Reproduction
There are numerous hormones in the human body that play key factors in allowing a human being to reproduce successfully.

Spermatogenesis
Spermatogenesis is the 65 to 75 day process in which the human male anatomy produces sperm cells. In the male body, follicle-stimulating hormones, or FSH, and leutinizing hormones, or LH, are very important in the process of spermatogenesis. These hormones control sperm reproduction. The production of the hormones testosterone and androgens are stimulated by the leutinizing hormones. During this process, the follicle-stimulating hormones motivate the testes to produce sperm. The development of the sperm takes place in twisted tubules called seminiferous tubules. Mitosis occurs, in which the diploid cells multiply themselves constantly. Then, day by day, at least 3 million of these cells begin to undergo meiosis, where the number of doubled chromosomes is reduced in half by dividing the cell over and over again. In order for the first phase of Meiosis to begin, the cell must become a primary spermatocyte. After this has occurred, the diploid cell, which has 46 chromosomes, split into two haploid secondary spermatocytes, each containing only 23 chromosomes. In the next phase of Meiosis, Meiosis II, the two cells split, again, forming four cells also consisting of 23 chromosomes, and the cell undergoes the change in order to perform its more specialized function for reproduction. This production takes place in the male gonads, also known as the testes.

Oogenesis
Oogenesis, also called ovigenesis, is the process in which the female anatomy produces egg cells. The egg cell is made up of three layers: a jelly coat, the vitelline layer, and the egg cell's plasma membrane. A hormone called gonadotropin releasing hormone, or GnRH, control the production of the follicle-stimulating hormones and the leutinizing hormones that, as stated above, are also found in the male body. The process of oogenesis is similar to spermatogenesis. Although produced by the leutinizing hormones, the androgen hormones control the levels of FSH, GnRH, as well as the LH. Oogenesis begins before birth. Each follicle in the uterus that all females are born with holds an undeveloped primary occyte. Similar to the primary spermatocyte, the primary oocyte is a diploid cell that has to divide into two haploid cells in order to complete Meiosis I. When puberty begins for females, the FSH arouses one of the undeveloped primary oocytes to develop. This causes the follicle to expand, completing Meiosis I. The difference between the Meiosis of the two processes, though, is that when the oocyte divides for Meiosis II, the amount of cytoplasm between the two daughter cells is imbalanced. The cell with the most cytoplasm is called the secondary oocyte. This is the cell that released in ovulation.

Fertilization
Fertilization is the outcome of the joining of a sperm cell and an egg cell to form what is called a diploid cell. A diploid cell is a cell that contains two sets of chromosomes that were inherited from each parent cell. The cell will eventually develop into another human being. It is a process that is a result of a series of events which happens in sexual reproduction. The hormones of the male and female body are what trigger the beginning of this process. Other than FHS, GnRH, and LH, the other hormones that help regulate the female cycle is estrogen and progesterone. The proliferate phase is the first half of a female's cycle in which the mucous membrane of the uterine wall thickens. The FSH causes ovaries to secrete estrogen and the follicle of the uterus to fully develop. Ovulation is caused by the hypothalamus secreting large amounts of GnRH by the...
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