The hypothalamus is responsible for controlling homeostasis, which helps in keeping the body functional and stable. In doing so, it responds to internal and external stimuli, including temperature change, feelings, hunger, blood circulation, and pressure. To accomplish all these functions, the hypothalamus produces hormones that regulate and respond to these stimuli. Most of these hormones are produces according to the stimulus received and the interpretation of the hypothalamus of the stimuli. When the ADH says “most of the rest us” in reference to the sentence that states “first they are told to do one job, and then they told to stop” to show the confusion the hormones have, it is referring to the fact that most hormones are produced according to the stimulus reaching the hypothalamus. The hormones referred to in this context are antidiuretic hormone (ADH) that is responsible for water absorption, the gonadotropin-releasing hormone that is responsible for giving the pituitary gland instructions to release the sexual hormone, the corticotropin-releasing hormone which gives the pituitary glands instructions to release steroids, the thyrotropin-releasing hormone that activates specific glands called the thyroid, and the prolactin controlling hormone which is responsible for controlling the pituitary gland response to breast milk release.
The hormone excluded in this statement is oxytocin, which performs an array of functions from temperature regulation to breastfeeding and keeping tabs on the sleep cycle and the growth hormone responsible for growth. They are excluded because they are not released in response to a particular stimulus but at a specific period. Therefore, they do not encounter being “told to do something then again told to stop.”
In females, the menstrual cycle is the chemical and biological changes in response to sexual reproduction. The process is monitored and controlled by hormones that are produced in the endocrine system. The process occurs in phases, and the absence of FSH and LH will hinder these phases’ smooth going. The phases are:
1. The Follicular Phase
It is the phase where the follicle in the ovary matures and is ready to be released hence the name follicular phase. The hormone involved at this stage is estradiol. During this stage, the follicle-stimulating hormone (FSH) is released from the anterior pituitary gland. Its release is gradual and is at its peak at the ending of the last menstrual cycle. It triggers the Graafian or antral follicles that always compete to be dominant. The FSH triggers the proliferation of the uterine lining, particularly the granulosa cells in the earlier stages of follicles, and results in Luteinizing hormone (LH) receptors on the granulosa cells. During the gradual release of LH, one of the follicles becomes dominant and lowers LH and FSH levels. The lowered levels result in atresia of the follicles, but the dominant follicle continues to mature. At this stage, the estrogen level is high and initiates the creation of a new uterine lining called the endometrium, and the crypts reduce the vagina acidity in the cervix.
The matured ovarian follicle is self-destroyed and given off as an egg, also known as the ovum or the oocyte, in a process called ovulation, and this process is called the periovulatory period. The debris given away during this process is called menses.
3. Luteal Phase
The Luteal phase is the end phase of the menstrual cycle, also known as the secretory phase. It is triggered by the formation of the corpus luteum and is completed either in pregnancy or luteolysis. It is controlled by the progesterone hormone, which increases its level during this stage. The FSH and LH after ovulation turn into corpus luteum. It is the corpus luteum that grows to produce progesterone and traces of estrogen. The hormone progesterone is responsible for the activation of endometrium receptivity for the blastocyst’s attachment. The corpus luteum produces hormones that kill the production of FSH and LH and eventually atrophy. If the embryo is implanted, the atrophy of the corpus luteum can be prevented by producing hCG (human chorionic gonadotropin), which is similar to LH and preserves the corpus luteum.
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