Overview : The vulva is a part of the female reproductive system and is also part of the external genitalia. The vulva consists of labia minora, labia majora, mons pubis, clitoris, vestibular bulb, vulval vestibule, urinary meatus the vaginal opening, hymen, and Bartholin's glands. other parts of the vulva include sebaceous glands, urogenital triangle, and pudendal cleft. Pelvic floor muscles support the structures of the vulva and vulva including the entrance to the vagina. Vulva goes through changes during childhood, puberty, menopause, and post-menopause. Structure: A) Mons pubis: it is present in both sexes and act as a cushion during sexual intercourse and is more pronounced in female. the mons pubis is a soft fatty tissue at the front of the vulva in the pubic region covering the pubic bone. the lower part of the mons pubis is divided by a fissure called pudendal cleft. it separates mons pubis and labia majora, the mons pubis, and labia majora get covered by pubic hair at pu...
How erection occurs - mechanism | components | disorders of erection
Overview
Erection is a process occurring as a result of erotic psychological stimuli.A normal erection is a neurovascular event relying on intact nerve supply, blood supply, and the tone of the muscles responsible for erection.
"The basic concept in the erection is an increase in the inflow of blood to penis with a subsequent decrease in the outflow".
How erection occurs?
Erotic psychological stimuli to the http://brain result in stimulating the brain to generate sexual feelings and to release specific hormones called neurotransmitters which causes an increase in the blood to the http://penis (vasodilation)and also a decrease in the outflow ( vasoconstriction).Erotic psychological stimuli
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Brain
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release of hormones(Neurotransmitters)
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Vasodilation
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Erection
Muscles responsible for erection -
There are three muscles for causing and maintaining an erection, these three muscle groups cause erection by active contraction and relaxation.Following 3 muscles are responsible for erection :
1)Corpora cavernosa (paired)
2)Bulbocavernosus
3)Ischiocavernosus
Active contraction of bulbocavernosus and ischiocavernosus with the relaxation of paired corpora cavernosa causes an erection. contraction of bulbocavernosus and ischiocavernosus adds rigidity to the penis during erection. Pelvic floor muscles also contribute to an erection.
Neurotransmitters responsible for erection -
a neurotransmitter is a messenger secreted from the brain that signals the muscles and blood vessels of the penis to cause an erection.Neurotransmitters responsible for erection are as follows :
1)Nitric oxide - nitric oxide is a key neurotransmitter that causes and sustains an erection. It is also the first neurotransmitter secreted by the brain to cause an erection.
2)Acetylcholine
3)Prostaglandins
4)Vasoactive intestinal peptide (VIP)
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