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Testosterone/Estrogen: Oocyte and Spermatocyte

Kolby Wesson and Chad GutierrezAP Biology2/22/15

+Oocyte and

Spermatocyte

An acrosome contains enzymes that digest the egg cell coating, thus permitting the sperm to enter the egg.

A flagellum is a long, lash-like appendage that gives the sperm the ability to swim to the egg.

The mitochondria give the sperm the energy to swim to the oocyte for fertilization

Lipid droplets are the lipid storage organelles of all organisms.

A polar body is a cell that separates from an oocyte during meiosis and that contains a nucleus produced in the first or second meiotic division and very little cytoplasm.

The jelly coat prevents too many sperm from getting to the egg at the same time, because of its viscosity

(http://www.mrothery.co.uk/cellcycleandrepro/cellcycleandrepronotes.htm)

+Follicle Stimulating Hormone

Follicle stimulating hormone is one of the gonadotrophic hormones, the other being luteinizing hormone

Both are released by the pituitary gland into the bloodstream. Follicle stimulating hormone is one of the hormones essential to pubertal development and the function of women’s ovaries and men’s testes

In women, this hormone stimulates the growth of ovarian follicles in the ovary before the release of an egg from one follicle at ovulation

In men, the hormone acts on Sertoli cells of the testes to stimulate sperm production (spermatogenesis)

(http://www.vupdateu.com/2012/05/pituitary-gland/)

+Spermatocyte: Erection

Physical and/or mental stimulation cause nerves in the brain to send chemical messages to nerves in the penis telling the penile blood vessels to relax so that blood can flow freely into the penis

Once in the penis, high pressure traps the blood within both corpora cavernosa. This causes the penis to expand and sustain an erection

(http://www.webmd.com/erectile-dysfunction/how-an-erection-occurs)

+Spermatocyte: Ejaculation

Ejaculation (the release of sperm at climax) is triggered when the man reaches a critical level of excitement

Sexual stimulation causes nerves in the penis to send chemical messages or impulses to the spinal cord and into the brain where other chemical messages are sent back to the penis (via the spinal cord) causing ejaculation

Ejaculation has two phases During the first phase the vas deferens (the tubes which

store and transport sperm from the testes) contract to squeeze sperm toward the back of the urethra

During the second phase, the posterior urethra senses the secretions within it (at the height of sexual excitement) and sends signals to the spinal cord to, in turn, send powerful signals to the muscles at the base of penis to vigorously contract every 0.8 seconds and force the semen out of the penis and into the vagina

+Spermatocyte: Path to the

Oocyte Once the sperm enters the vagina, it has a treacherous journey Once in the cervical canal the sperm is in a sea of cervical

mucus. As a woman approaches ovulation, the mucus becomes stretchy, clear, and thin. The changes happen on a microscopic level as well, as strings of molecules line up like train tracks so that sperm can hop on and ride to their destination

A just-ejaculated sperm cell has to spend about an hour going through biochemical changes, picking up speed as it makes its way into the uterus and fallopian tubes to find its target (the oocyte)

The sperm must reach its destination (the oocyte) which is slowly making its way down the fallopian tube from your ovary — within the right time frame

If they get there too early, they risk dying before the egg shows up. Too late, and the egg will be gone and they'll have missed their shot

+Spermatocyte: Path to the

Oocyte They also need to pick their destination carefully — an egg is usually only present in one of your two fallopian tubes in any given month

Even the sperm who reach the egg still has to outrace the other hundreds to be the first one to plow through the hard outer layer of the egg

The first one through the outer layer of the egg will reach the egg's nucleus, where the sperm will then release its own genetic contribution

As soon as the one lucky sperm cell succeeds in penetrating the egg, the egg immediately undergoes a chemical reaction that prevents other sperm cells from penetrating as well

Then the chromosomes carried by the sperm and egg come together, and the egg is officially fertilized

(http://www.wisegeek.com/what-are-sperm-cells.htm)

+Spermatocyte: Testosterone

Testosterone is the main sex hormone that men have Testosterone helps bring on the physical changes that turn a

boy into a man including the growth of the penis and testes The brain and pituitary gland, a small gland at the base of the

brain control production of testosterone by the testes Low testosterone can result in a drop in sex drive, poor

erections, and low sperm count Women’s ovaries also make testosterone, though in much

smaller amounts

(http://www.lowspermcount.org/images/low-sperm-count.gif)

+Oocyte

In the first half of a woman’s menstrual cycle, levels of estrogen start to rise. Estrogen makes the lining of the uterus (womb) grow and thicken. This lining of the womb is a place that will nourish the embryo if a pregnancy occurs

At the same time the lining of the womb is growing, an egg, or ovum, in one of the ovaries starts to mature. At about day 14 of an average 28-day cycle, the egg leaves the ovary (this is called ovulation)

After the egg has left the ovary, it travels through the fallopian tube to the uterus

An egg lives 12-24 hours after leaving the ovary, so the meeting of egg and sperm has to occur within this time

A woman becomes pregnant if the egg is fertilized by a man’s sperm cell and attaches to the uterine wall. If the egg is not fertilized, it will break apart

+Oocyte: Estrogen

Estrogen is the main sex hormone that women have In women, estrogen is produced mainly in the ovaries, but it is

also produced by fat cells and the adrenal gland Estrogen helps regulate the menstrual cycle, controlling the

growth of the uterine lining during the first part of the cycle If the woman's egg is not fertilized, estrogen levels decrease

sharply and menstruation begins If the egg is fertilized, estrogen works with progesterone, another

hormone, to stop ovulation during pregnancy

(http://www.sexualityandu.ca/sexual-health/all-about-menstruation/all-about-menstrual-cycle)

+Homeostasis

Spermatocyte: Temperature regulation Scrotum will contract if too cold, and will loosen when too

hot in order to keep sperm cells at optimal temperature Sperm needs to be kept at a temperature 1-2 degrees lower

than normal body temperature

Oocyte: pH regulation The normal pH of the vagina is 4.5 or less (acidic) This low pH helps to maintain a healthy balance of the yeast

and bacteria that normally live in the vagina If vaginal pH is raised, the normal balance of organisms can

be upset, resulting in an inflammation known as vaginitis Semen carries a pH of 7.1 to 8, so when these fluids are

introduced into the vagina pH levels will change in order to accommodate for the sperm

+Oocyte: Disease

Polycystic Ovary Syndrome

(PCOS) Irregular periods Excess androgens -- either

measured in the blood or seen through symptoms such as acne or excess hair growth 

Polycystic ovaries – infertility

Imbalanced hormones (testosterone and estrogen)

Follicle does not release an egg

(http://www.riversideonline.com/health_reference/Womens-Health/DS00423.cfm)

+Spermatocyte: Disease

Cystic Fibrosis

Causes infertility due to failure of the vas deferens Sperm cannot travel from the testes to the penis This is because the vas deferens do not develop properly Enjoy a normal daily and sex life Failure of reproduction in about 98% of cases

(http://www.cfmedicine.com/htmldocs/cftext/fertility.htm)

+Works Cited

“Fertility and Cystic Fibrosis.” Cystic Fibrosis Medicine.Cysticfibrosismedicine, 1 Apr. 2008

"Follicle-Stimulating Hormone." WebMD. WebMD. Web. 20 Feb. 2015. "How Fertilization Happens." What To Expect. Everyday Health. Web. 18 Feb.

2015.Jennings, Charles. "How Erections Work, Ejaculation, and Penis Anatomy

Image." WebMD. WebMD, 12 Sept. 2013. Web. 18 Feb. 2015."Male Reproductive System of Human." YouTube. YouTube, 16 Oct. 2012.

Web. 18 Feb. 2015.Mangan, P. "Testosterone Archives - Rogue Health and Fitness." Rogue Health and Fitness. WordPress, 3 Apr. 2014. Web. 18 Feb. 2015.Martel, Janelle. "Epididymitis." Healthline. Healthline Networks, 15 Aug.

2012. Web. 18 Feb. 2015.

+Works Cited

Mayo Clinic Staff. "Polycystic Ovary Syndrome (PCOS)." Mayo Clinic. Mayo Foundation for Medical Education and Research, 3 Sept. 2014. Web. 24 Feb. 2015. "Ovulation." BabyCentre. Babycenter, 1 Jan. 2015. Web. 18 Feb. 2015."Pituitary Gland." VupdateU. VupdateU. Web. 20 Feb. 2015.Rettner, Rachael. "What Is Estrogen?" LiveScience. TechMedia Network, 18 July

2014. Web. 18 Feb. 2015. Smith, Ingrid. "How to Maintain a Healthy Vaginal PH

Balance." LIVESTRONG.COM. LIVESTRONG.COM, 10 Mar. 2011. Web. 20 Feb. 2015. 

Tuggle, Alex. "Estrogen Dominance Symptoms and Estrogen Side Effects." Estrogen Dominance Symptoms and Estrogen Side Effects. Alex Tuggle. Web. 18 Feb. 2015.

"What Does Testosterone Do?" Hormone Health. Endocrine Society, 1 Jan. 2014. Web. 18 Feb. 2015.

Wilde, Marlene, and O. Wallace. WiseGeek. Conjecture. Web. 20 Feb. 2015.