Download E_AND_C_1

NAME:
Agbuza Edison Aidorkhai
DEPT:
Nursing science
MAT. NO: 13/MHS02/005
COLLEGE: M.H.S
ERECTION AND COITUS
ERECTION.
An erection (penile erection or penile tumescence) is a physiological
phenomenon in which the penis becomes firmer, engorged and enlarged. Penile
erection is the result of a complex interaction of psychological, neural, vascular
and endocrine factors, and is often associated with sexual arousal or sexual
attraction, although erections can also be spontaneous. The shape, angle and
direction of an erection varies considerably in humans.Physiologically, erection is
triggered by the parasympathetic division of the autonomic nervous system
(ANS), causing nitric oxide (a vasodilator) levels to rise in the trabecular arteries
and smooth muscle of the penis. The arteries dilate causing the corpora
cavernosa of the penis (and to a lesser extent the corpora spongiosum) to fill
with blood; simultaneously the ischiocavernosus and bulbospongiosus muscles
compress the veins of the corpora cavernosa restricting the egress and
circulation of this blood. Erection subsides when parasympathetic activity
reduces to baseline.As an autonomic nervous system response, an erection may
result from a variety of stimuli, including sexual stimulation and sexual arousal,
and is therefore not entirely under conscious control. Erections during sleep or
upon waking up are known as nocturnal penile tumescence (NPT). Absence of
nocturnal erection is commonly used to distinguish between physical and
psychological causes of erectile dysfunction and impotence.A penis which is
partly, but not fully, erect is sometimes known as a semi-erection (partial
tumescence); a penis which is not erect is typically referred to as being flaccid, or
soft.An erection occurs when two tubular structures, called the corpora
cavernosa, that run the length of the penis, become engorged with venous blood.
This may result from any of various physiological stimuli, also known as sexual
stimulation and sexual arousal. The corpus spongiosum is a single tubular
structure located just below the corpora cavernosa, which contains the urethra,
through which urine and semen pass during urination and ejaculation
respectively. This may also become slightly engorged with blood, but less so than
the corpora cavernosa.
CLINICAL PHYSIOLOGY.
Erectile dysfunction (also known as ED or "(male) impotence") is a sexual
dysfunction characterized by the inability to develop and/or maintain an
erection. The study of erectile dysfunction within medicine is known as
andrology, a sub-field within urology.Erectile dysfunction can occur due to both
physiological and psychological reasons, most of which are amenable to
treatment. Common physiological reasons include diabetes, kidney disease,
chronic alcoholism, multiple sclerosis, atherosclerosis, vascular disease, and
neurologic disease which collectively account for about 70 percent of ED cases.
Some drugs used to treat other conditions, such as lithium and paroxetine, may
cause erectile dysfunction. Erectile dysfunction, tied closely as it is to cultural
notions of potency, success and masculinity, can have devastating psychological
consequences including feelings of shame, loss or inadequacy; there is a strong
culture of silence and inability to discuss the matter. In fact, around one in ten
men will experience recurring impotence problems at some point in their lives
Priapism
Priapism is a medical condition which could possibly be painful, and is a
prolonged erection at least four hours long, which does not return to its flaccid
state, despite the absence of both physical and psychological stimulation.
COITUS
Sexual intercourse, or coitus or copulation, is principally the insertion and
thrusting of a male's penis, usually when erect, into a female's vagina for the
purposes of sexual pleasure, reproduction, or both. This is also known as vaginal
intercourse or vaginal sex. Other forms of penetrative sexual intercourse include
penetration of the anus by the penis (anal sex), penetration of the mouth by the
penis or oral penetration of the female genitalia (oral sex), sexual penetration by
the fingers (fingering), and penetration by use of a strap-on dildo. These activities
involve physical intimacy between two or more individuals and are usually used
among humans solely for physical or emotional pleasure and commonly
contribute to human bonding.A variety of views concern what constitutes sexual
intercourse or other sexual activity, which can also impact views on sexual
health. Although the term sexual intercourse, particularly the variant coitus,
generally denotes penile-vagina penetration and the possibility of creating
offspring (which is the fertilization process known as reproduction),it also
commonly denotes penetrative oral sex and particularly penile-anal sex. Nonpenetrative sex acts, such as non-penetrative forms of cunnilingus or mutual
masturbation, have been termed outer course, but may additionally be
considered sexual intercourse. The term sex, often a shorthand for sexual
intercourse, can mean any form of sexual activity. Because people can be at risk
of contracting sexually transmitted infections during sexual activities, though the
transmission risk is significantly reduced during non-penetrative sex, safe sex
practices are advised. Sexual intercourse is perhaps 385 million years old, and it is
likely that the oldest jawed fish on Earth was the first animal to reproduce by
copulation. Reproduction among humans usually occurs with penile-vaginal
penetration. Male orgasm usually includes ejaculation, a series of muscular
contractions that deliver semen containing male gametes known as sperm cells
or spermatozoa from the penis into the vagina. The subsequent route of the
sperm from the vault of the vagina is through the cervix and into the uterus, and
then into the fallopian tubes. Millions of sperm are present in each ejaculation,
to increase the chances of one fertilizing an egg or ovum (see sperm
competition). When a fertile ovum from the female is present in the fallopian
tubes, the male gamete joins with the ovum, resulting in fertilization and the
formation of a new embryo. When a fertilized ovum reaches the uterus, it
becomes implanted in the lining of the uterus (the endometrium) and a
pregnancy begins. Unlike most species, human sexual activity is not linked to
periods of estrus and can take place at any time during the reproductive cycle,
even during pregnancy.When a sperm donor has sexual intercourse with a
woman who is not his partner and for the sole purpose of impregnating the
woman, this may be known as natural insemination, as opposed to artificial
insemination. Artificial insemination is a form of assisted reproductive
technology, which are methods used to achieve pregnancy by artificial or
partially artificial means. For artificial insemination, sperm donors may donate
their sperm through a sperm bank, and the insemination is performed with the
express intention of attempting to impregnate the female; to this extent, its
purpose is the medical equivalent of sexual intercourse.
CLINICAL PHYSIOLOGY
In humans, sexual intercourse and sexual activity in general have been
reported as having health benefits as varied as increased immunity by increasing
the body's production of antibodies and subsequent lower blood pressure, and
decreased risk of prostate cancer. Sexual intimacy and orgasms increase levels of
the hormone oxytocin (also known as "the love hormone"), which can help
people bond and build trust. A long-term study of 3,500 people between ages 18
and 102 by clinical neuropsychologist David Weeks indicated that, based on
impartial ratings of the subjects' photographs, sex on a regular basis helps people
look significantly chronologically younger.