Question – 20 Bonus 10

Assignment –

The Sperm and the Egg

Describe the life of a sperm and the life of an egg from start to finish in a 700- to 1,050- word story based on this week’s reading and formatted according to APA guidelines. Cover the following points in your story:

o Trace the movements of the sperm and the egg from their development to fertilization. o Describe the function of each of the male and female internal and external sex organs in relation to the sperm and the egg. o Describe the role of the sex organs in fertilization. o Be creative. Consider giving the sperm and egg personalities as you describe their traveling adventures.

Example that needs to be altered. Great basis for requirements though –

The Life of a Sperm and the Life of an Egg from Start to Finish

This is a story about Zak the Sperm, and Zoie the Egg. This is an exciting day for Zak and Zoie because they are going to get fertilized today. Fertilization is the moment Zak and Zoie fuse together and a new individual

begins to form. Zoie has been waiting for this day for 32 years, since her egg was produced when she was in the fetal ovaries, along with five million others, but today she is the chosen one! Zak feels like he has won the lotto because he is the only one out of 500 million mobile sperm discharged today, in one ejaculation that will get to fertilize!

Zak's day. Zak's life begins in the seminiferous tubules, inside the testes, where he has been maturing about two months. Before the great ejaculation he moves to the epididymis waiting for the great force that pushes him through the urethra. In the urethra he is mixed with a secretion from the prostate gland containing substances that facilitate his long journey to the female ovum, or Zoie. First, Zak the Sperm and the prostate secretion are discharged with immense force by the way of contractions of the pelvic muscles, and then they are followed by a sugar-containing fluid from the seminal vesicles (glands emptying into the vas deferens). From there he exits the penis into the vagina where his journey of fertilization begins. The Life of a Sperm and the Life of an Egg from Start to Finish

Zoie's day. Zoie has had a much longer life than Zak because she was formed while still in the fetus of a human being. Her chances of becoming fertilized are about one in 500 million, even then a women's body only

ovulates about 400 times altogether in a lifetime. Her time of ovulation is a dynamic process that takes place in the course of one or more minutes. The portion of the follicile facing the abdominal cavity ruptures fairly rapidly and the fluid filling the follicle and containing millions of cells runs out. Inside the vast number of cells is the ovum a.k.a, Zoie (very valuable cargo). There Zoie is surrounded by thousands of cells that provide nourishment and protection for the journey. In the meantime, the Fallopian tubes have received signals to get ready to capture this precious cargo. The finger-like projections of the fallopian tube have captured Zoie, which is still surrounded by thousands of nutrient cells. Now Zoie is safe inside the Fallopian tube, where she will wait rather content while she ripens, preparing herself for the meeting of Zak (who has had quite an adventurous day himself)! Inside the fallopian tubes is where fertilization will take place.

Fertilization time. Zak has been ejaculated against the opening of the cervix, the furthest end of the vagina. His journey is about six to seven inches to the fallopian tubes but can take several hours. Zak is a high-speed swimmer though, and the vagina has favorable conditions today, so he makes it in about a half an hour. Unbeknownst to Zak he already starts to change during his journey. Because he has been affected by substances in the cervix, uterus and Fallopian tubes, he has become what is termed "capacitated" or capable of fertilizing Zoie. Lucky for Zak, Zoie has already gone through the dynamic process of ovulation and is awaiting his arrival, he does not have to swim the tube awaiting her arrival; some sperm have been known to wait for several days. Today Zak, being the smart one he is, also full of mitochondria (the sperms energy) propels him forward, him and about one hundred others have made it thus far to Zoie's outer wall. Zak and the others start drilling their tiny heads and beating it with their tails, causing Zoie to rotate counterclockwise. Because Zoie is still covered by the sheath of nutrient cells, Zak must clear them away. The cap of Zak, the acrosome, disappears and enzymes are released, this helps Zak to disrobe Zoie so he can penetrate through her wall. During this process many of Zak's buddies parish but Zak keeps pushing forward, determined to have fusion! He feels it, the moment him and a couple other sperm are on their way through Zoie's wall, he breaks all the way through, penetrating the inner cell plasma of Zoie. Something remarkable happens; Zoie is overtaken by a chemical composition that changes, that shuts out other sperm even if they have almost pierced it. No time for goodbye's after Zak's long journey with his buddies, Zoie's doors are bolted shut, he has accomplished what 500 million sperm had set out to do just a few hour ago! He has won the gold medal! The Life of a Sperm and the Life of an Egg from Start to Finish

Inner sanctum. Finally after at least 20,000 tail lashings, Zak has reached Zoie. Little does he know he still has some way to go until he reaches the inner cell of Zoie. Zak now works like a revolving drill, with his

head rotating by his tail movements. He has now inserted his head passing entirely through the ovum wall, and is about to penetrate the inner cell membrane. The head of the sperm has penetrated Zoie's plasma and is steadily approaching the genetic material, which is stored in a nucleus deep inside Zoie. Both their nuclei are drawn inexorably toward each other and soon fuse. Instantaneously, numerous hereditary characteristics of the new individual are determined.

References

Human Embryology. (2008). In Encyclopædia Britannica. Retrieved July 7, 2008, from Encyclopædia Britannica Online: http://www.search.eb.com.ezproxy.apollolibrary.com/eb/article-9110650

Lennart Nilsson, L. H. (1990). In The Begining. In L. H. Lennart Nilsson, A Child Is Born (pp. 11-55). New York: