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Erectile Function
An erection (clinically: penile erection or penile tumescence) is a physiological phenomenon in which the penis becomes firm, 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, sexual attraction or libido, although erections can also be spontaneous. The shape, angle, and direction of an erection vary considerably between humans. Physiologically, an erection is required for a male to effect penetration or sexual intercourse and is triggered by the parasympathetic division of the autonomic nervous system, causing the levels of nitric oxide (a vasodilator) 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 corpus spongiosum) to fill with blood; simultaneously the ischiocavernosus and bulbospongiosus muscles compress the veins of the corpora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physiology
Physiology (; ) is the science, scientific study of function (biology), functions and mechanism (biology), mechanisms in a life, living system. As a branches of science, subdiscipline of biology, physiology focuses on how organisms, organ systems, individual organ (biology), organs, cell (biology), cells, and biomolecules carry out chemistry, chemical and physics, physical functions in a living system. According to the classes of organisms, the field can be divided into clinical physiology, medical physiology, Zoology#Physiology, animal physiology, plant physiology, cell physiology, and comparative physiology. Central to physiological functioning are biophysics, biophysical and biochemical processes, homeostasis, homeostatic control mechanisms, and cell signaling, communication between cells. ''Physiological state'' is the condition of normal function. In contrast, ''pathology, pathological state'' refers to abnormality (behavior), abnormal conditions, including human diseases. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ischiocavernosus Muscle
The ischiocavernosus muscle (erectores penis ''or'' erector clitoridis in older texts) is a muscle just below the surface of the perineum, present in both men and women. Structure It arises by tendinous and fleshy fibers from the inner surface of the tuberosity of the ischium, behind the crus penis; and from the inferior pubic rami and ischium on either side of the crus. From these points fleshy fibers succeed, and end in an aponeurosis which is inserted into the sides and under surface of the crus penis. Function In females, the ischiocavernosus muscle assists with clitoral erection. In males, it helps to stabilize the erect penis by compressing the crus penis and retarding the return of blood through the veins. Additional images File:Gray236.png, Right hip bone. Internal surface. File:Gray407.png, Coronal section of anterior part of pelvis, through the pubic arch. Seen from in front. File:Gray542.png, The superficial branches of the internal pudendal artery. Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urine
Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (males) or urethral meatus of the vulva (females) during urination. In other vertebrates, urine is excreted through the cloaca. Urine contains water-soluble by-products of Cell (biology), cellular metabolism that are rich in nitrogen and must be clearance (medicine), cleared from the Circulatory system, bloodstream, such as urea, uric acid and creatinine. A urinalysis can detect nitrogenous wastes of the mammalian body. Urine plays an important role in the earth's nitrogen cycle. In balanced ecosystems, urine fertilizes the soil and thus helps plants to grow. Therefore, Reuse of excreta, urine can be used as a fertilizer. Some animals use it to territory (animal)#Scent marking, mark their territories. Historically, aged or fermented urine (kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urethra
The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate. The external urethral sphincter is a striated muscle that allows voluntary control over urination. The Internal urethral sphincter, internal sphincter, formed by the involuntary smooth muscles lining the bladder neck and urethra, receives its nerve supply by the Sympathetic nervous system, sympathetic division of the autonomic nervous system. The internal sphincter is present both in males and females. Structure The urethra is a fibrous and muscular tube which connects the urinary bladder to the external urethral meatus. Its length differs between the sexes, because it passes through the penis in males. Male In the human male, the urethra is on average long and opens at the end of the external urethral meatus. The urethra is divided into four parts in men, named after the lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physiology
Physiology (; ) is the science, scientific study of function (biology), functions and mechanism (biology), mechanisms in a life, living system. As a branches of science, subdiscipline of biology, physiology focuses on how organisms, organ systems, individual organ (biology), organs, cell (biology), cells, and biomolecules carry out chemistry, chemical and physics, physical functions in a living system. According to the classes of organisms, the field can be divided into clinical physiology, medical physiology, Zoology#Physiology, animal physiology, plant physiology, cell physiology, and comparative physiology. Central to physiological functioning are biophysics, biophysical and biochemical processes, homeostasis, homeostatic control mechanisms, and cell signaling, communication between cells. ''Physiological state'' is the condition of normal function. In contrast, ''pathology, pathological state'' refers to abnormality (behavior), abnormal conditions, including human diseases. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venous Blood
Venous blood is deoxygenated blood which travels from the peripheral blood vessels, through the venous system into the right atrium of the heart. Deoxygenated blood is then pumped by the right ventricle to the lungs via the pulmonary artery which is divided in two branches, left and right to the left and right lungs respectively. Blood is oxygenated in the lungs and returns to the left atrium through the pulmonary veins. Venous blood is typically colder than arterial blood, and has a lower oxygen content and pH. It also has lower concentrations of glucose and other nutrients and has higher concentrations of urea and other waste products. The difference in the oxygen content of arterial blood and venous blood is known as the arteriovenous oxygen difference. Most medical laboratory tests are conducted on venous blood, with the exception of arterial blood gas tests. Venous blood is obtained for lab work by venipuncture In medicine, venipuncture or venepuncture is the proce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Puberty
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a female, the testicles in a male. In response to the signals, the gonads produce hormones that stimulate libido and the growth, function, and transformation of the brain, bones, muscle, blood, skin, hair, breasts, and sex organs. Physical growth—height and weight—accelerates in the first half of puberty and is completed when an adult body has been developed. Before puberty, the external sex organs, known as primary sexual characteristics, are sex characteristics that distinguish males and females. Puberty leads to sexual dimorphism through the development of the secondary sex characteristics, which further distinguish the sexes. On average, females begin puberty at age 10½ and complete puberty at ages 15-17; males begin at ages 11½-12 and complete pube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artificial Insemination
Artificial insemination is the deliberate introduction of sperm into a female's cervix or uterine cavity for the purpose of achieving a pregnancy through in vivo fertilization by means other than sexual intercourse. It is a fertility treatment for humans, and is a common practice in animal breeding, including dairy cattle (see frozen bovine semen) and pigs. Artificial insemination may employ assisted reproductive technology, sperm donation and animal husbandry techniques. Artificial insemination techniques available include intracervical insemination (ICI) and intrauterine insemination (IUI). Where gametes from a third party are used, the procedure may be known as 'assisted insemination'. Humans History The first recorded case of artificial insemination was John Hunter in 1790, who helped impregnate a linen draper's wife. The first reported case of artificial insemination by donor occurred in 1884: William H. Pancoast, a professor in Philadelphia, took sperm from hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insemination
Insemination is the introduction of sperm (in semen) into a female or hermaphrodite's reproductive system in order to fertilize the ovum through sexual reproduction. The sperm enters into the uterus of a mammal or the oviduct of an oviparous (egg-laying) animal. Female humans and other mammals are inseminated during sexual intercourse or copulation, but can also be inseminated by artificial insemination. In humans, the act and form of insemination has legal, moral and interpersonal implications. However, whether insemination takes place naturally or by artificial means, the pregnancy and the progress of it will be the same. Insemination may be called in vivo fertilisation (from ''in vivo'' meaning "within the living") because an egg is fertilized inside the body, this is in contrast with in vitro fertilisation (IVF). Plants In plants, the fertilization process is referred to as pollination. It is the process of transfer of pollen grains from one anther to the stigma of oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impotence
Erectile dysfunction (ED), also referred to as impotence, is a form of sexual dysfunction in males characterized by the persistent or recurring inability to achieve or maintain a Human penis, penile erection with sufficient rigidity and duration for satisfactory sexual activity. It is the most common sexual problem in males and can cause psychological distress due to its impact on self-image and sexual relationships. The majority of ED cases are attributed to physical risk factors and predictive factors. These factors can be categorized as vascular, neurological, local penile, hormonal, and drug-induced. Notable predictors of ED include aging, cardiovascular disease, diabetes mellitus, Hypertension, high blood pressure, obesity, Dyslipidemia, abnormal lipid levels in the blood, hypogonadism, smoking, Depression (mood), depression, and Adverse drug reactions, medication use. Approximately 10% of cases are linked to psychosocial factors, encompassing conditions such as depressio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nocturnal Penile Tumescence
Nocturnal penile tumescence (NPT) is a spontaneous erection of the penis during sleep or when waking up. Along with nocturnal clitoral tumescence, it is also known as sleep-related erection. Colloquially, the term morning wood, or less commonly, morning glory is also used, although this is more commonly used to refer specifically to an erection ''beginning'' during sleep and persisting into the period just after waking. Men without physiological erectile dysfunction or severe depression experience nocturnal penile tumescence, usually three to five times during a period of sleep, typically during rapid eye movement sleep. Nocturnal penile tumescence is believed to contribute to penile health. Mechanism The cause of nocturnal penile tumescence is not known with certainty. In a wakeful state, in the presence of mechanical stimulation with or without an arousal, erection is initiated by the parasympathetic division of the autonomic nervous system with minimal input from the central ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
