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Old 09-20-2012
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Default Histology Qs

Which of the following occurs at the darkly stained band indicated by the arrow?

A. Acrosome reaction
B. Aromatase acts on testosterone
C. Capacitation
D. Implantation receptors are exhibited
E. Meiosis is resumed
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Old 09-20-2012
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Default A. Acrosome reaction

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Originally Posted by Fuser00 View Post
Which of the following occurs at the darkly stained band indicated by the arrow?

A. Acrosome reaction
B. Aromatase acts on testosterone
C. Capacitation
D. Implantation receptors are exhibited
E. Meiosis is resumed
I am kinda bad in histo slides (really bad in lot of things)
Anyways is this ovum?
it looks so
according to arrow shown at this place penetrating sperm would loose its tail. May be it's A. Acrosome reaction
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a) acrosome rxn
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Old 09-20-2012
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Default my answer :)

A. Acrosome reaction - I think it's zona pellucida
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Old 09-20-2012
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Correct Answer CORRECT ANSWER: A.....the explanation

The photomicrograph depicts an oocyte. The zona pellucida at the arrow is similar to a thick basal lamina and is composed of glycoproteins that bind to the cell membrane of the sperm head. This binding triggers the acrosome reaction, which involves fusion of the acrosomal membrane with the overlying sperm membrane. The acrosomal enzymes are released and digest the zona pellucida, allowing the spermatozoon to make contact and fuse with the ovum cell membrane.

The enzyme aromatase (choice B) is found in the granulosa cells, which surround the oocyte and the follicular wall. Testosterone, produced by the theca cells, diffuses through the basal lamina of the follicle and is converted to estradiol by aromatase.

Capacitation (choice C) refers to changes that occur in the spermatozoa during their transit through the female reproductive tract. These changes occur in the oviducts and the uterus. Sperm become motile in the epididymis.

The oocyte divides many times as it moves toward the uterus, the zona pellucida disappearing. A portion of these cells will exhibit implantation receptors (choice D) and become an implantation site for the cell mass in the uterine wall.

Meiosis is resumed (choice E) in the oocyte shortly before ovulation. The nucleus of the oocyte can be seen in the center. The oocyte and the surrounding granulosa cells make up this structure, known as an antral or secondary follicle.
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