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Cremaster Muscle
The cremaster muscle is a paired structure made of thin layers of striated and smooth muscle that covers the testis and the spermatic cord in human males. It consists of the lateral and medial parts. Cremaster is an involuntary muscle, responsible for the cremasteric reflex; a protective and physiologic superficial reflex of the testicles. The reflex raises and lowers the testicles in order to keep them protected. Along with the dartos muscle of the scrotum, it regulates testicular temperature, thus aiding the process of spermatogenesis. Structure In human males, the cremaster muscle is a thin layer of striated muscle found in the inguinal canal and scrotum between the external and internal layers of spermatic fascia, surrounding the testis and spermatic cord. The cremaster muscle is a paired structure, there being one on each side of the body. Anatomically, the lateral cremaster muscle originates from the internal oblique muscle, just superior to the inguinal canal, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Oblique
The abdominal internal oblique muscle, also internal oblique muscle or interior oblique, is an abdominal muscle in the abdominal wall that lies below the external oblique muscle and just above the transverse abdominal muscle. Structure Its fibers run perpendicular to the external oblique muscle, beginning in the thoracolumbar fascia of the lower back, the anterior 2/3 of the iliac crest (upper part of hip bone) and the lateral half of the inguinal ligament. The muscle fibers run from these points superomedially (up and towards midline) to the muscle's insertions on the inferior borders of the 10th through 12th ribs and the linea alba. In males, the cremaster muscle is also attached to the internal oblique. Nerve supply The internal oblique is supplied by the lower intercostal nerves, as well as the iliohypogastric nerve and the ilioinguinal nerve. Function The internal oblique performs two major functions. Firstly as an accessory muscle of respiration, it acts as an ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Oblique
The abdominal internal oblique muscle, also internal oblique muscle or interior oblique, is an abdominal muscle in the abdominal wall that lies below the external oblique muscle and just above the transverse abdominal muscle. Structure Its fibers run perpendicular to the external oblique muscle, beginning in the thoracolumbar fascia of the lower back, the anterior 2/3 of the iliac crest (upper part of hip bone) and the lateral half of the inguinal ligament. The muscle fibers run from these points superomedially (up and towards midline) to the muscle's insertions on the inferior borders of the 10th through 12th ribs and the linea alba. In males, the cremaster muscle is also attached to the internal oblique. Nerve supply The internal oblique is supplied by the lower intercostal nerves, as well as the iliohypogastric nerve and the ilioinguinal nerve. Function The internal oblique performs two major functions. Firstly as an accessory muscle of respiration, it acts as an ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Stimulation
Sexual stimulation is any stimulus (including bodily contact) that leads to, enhances and maintains sexual arousal, and may lead to orgasm. Although sexual arousal may arise without physical stimulation, achieving orgasm usually requires physical sexual stimulation. The term ''sexual stimulation'' often implies stimulation of the genitals, but may also include stimulation of other areas of the body, stimulation of the senses (such as sight or hearing) and mental stimulation (i.e. from reading or fantasizing). Sufficient stimulation of the penis or clitoris usually results in an orgasm. Stimulation can be by self (e.g., masturbation) or by a sexual partner (sexual intercourse or other sexual activity), by use of objects or tools, or by some combination of these methods. Some people practice orgasm control, whereby a person or their sexual partner controls the level of sexual stimulation to delay orgasm, and to prolong the sexual experience leading up to orgasm. Physical sexua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeostasis
In biology, homeostasis (British also homoeostasis) (/hɒmɪə(ʊ)ˈsteɪsɪs/) is the state of steady internal, physical, and chemical conditions maintained by living systems. This is the condition of optimal functioning for the organism and includes many variables, such as body temperature and fluid balance, being kept within certain pre-set limits (homeostatic range). Other variables include the pH of extracellular fluid, the concentrations of sodium, potassium and calcium ions, as well as that of the blood sugar level, and these need to be regulated despite changes in the environment, diet, or level of activity. Each of these variables is controlled by one or more regulators or homeostatic mechanisms, which together maintain life. Homeostasis is brought about by a natural resistance to change when already in the optimal conditions, and equilibrium is maintained by many regulatory mechanisms: it is thought to be the central motivation for all organic action. All home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dartos
The dartos fascia or simply dartos is a layer of connective tissue found in the penile shaft, foreskin, scrotum and labia. The penile portion is referred to as the superficial fascia of penis or the subcutaneous tissue of penis, while the scrotal part is the dartos proper. In addition to being continuous with itself between the scrotum and the penis, it is also continuous with Colles fascia of the perineum and Scarpa's fascia of the abdomen. The dartos lies just below the skin, which places it just superficial to the external spermatic fascia in the scrotum and to Buck's fascia in the penile shaft. In the scrotum, it consists mostly of smooth muscle. The tone of this smooth muscle is responsible for the wrinkled (rugose) appearance of the scrotum. In females, the same muscle fibers are less well developed and termed ''dartos muliebris,'' lying beneath the skin of the labia majora. The dartos fascia receives innervation from postganglionic sympathetic nerve fibers arriving via t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatozoon
A spermatozoon (; also spelled spermatozoön; ; ) is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote. (A zygote is a single cell, with a complete set of chromosomes, that normally develops into an embryo.) Sperm cells contribute approximately half of the nuclear genetic information to the diploid offspring (excluding, in most cases, mitochondrial DNA). In mammals, the sex of the offspring is determined by the sperm cell: a spermatozoon bearing an X chromosome will lead to a female (XX) offspring, while one bearing a Y chromosome will lead to a male (XY) offspring. Sperm cells were first observed in Antonie van Leeuwenhoek's laboratory in 1677. Mammalian spermatozoon structure, function, and size Humans The human sperm cell is the reproductive cell in males and will only survive in warm environments; once it leaves the male body the sperm's survival likelihood is reduced and it may die, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Round Ligament Of Uterus
The round ligament of the uterus is a ligament that connects the uterus to the labia majora. Structure The round ligament of the uterus originates at the uterine horns, in the parametrium. The round ligament exits the pelvis via the deep inguinal ring. It passes through the inguinal canal, and continues on to the labia majora. At the labia majora, its fibers spread and mix with the tissue of the mons pubis. Development The round ligament develops from the gubernaculum which attaches the gonad to the labioscrotal swellings in the embryo. Blood supply The round ligament is supplied by the artery of the round ligament of uterus, also known as ''Sampson's artery''. Function The function of the round ligament is maintenance of the anteversion of the uterus (a position where the fundus of the uterus is turned forward at the junction of cervix and vagina) during pregnancy. Normally, the cardinal ligament is what supports the uterine angle (angle of anteversion). When the uteru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Nerve
A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the corresponding cervical, thoracic, lumbar, sacral and coccygeal regions of the spine. There are eight pairs of cervical nerves, twelve pairs of thoracic nerves, five pairs of lumbar nerves, five pairs of sacral nerves, and one pair of coccygeal nerves. The spinal nerves are part of the peripheral nervous system. Structure Each spinal nerve is a mixed nerve, formed from the combination of nerve fibers from its dorsal and ventral roots. The dorsal root is the afferent sensory root and carries sensory information to the brain. The ventral root is the efferent motor root and carries motor information from the brain. The spinal nerve emerges from the spinal column through an opening ( intervertebral foramen) between adjacent verteb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genitofemoral Nerve
The genitofemoral nerve refers to a nerve that is found in the abdomen. Its branches, the genital branch and femoral branch supply sensation to the upper anterior thigh, as well as the skin of the anterior scrotum in males and mons pubis in females. The femoral branch is different from the femoral nerve, which also arises from the lumbar plexus. Anatomy The genitofemoral nerve originates from the upper L1-2 segments of the lumbar plexus. It passes downwards, pierces the psoas major and emerges from its anterior surface. The nerve divides into two branches, the genital branch and the lumboinguinal nerve also known as the femoral branch, both of which then continue downwards and medially to the inguinal and femoral canal respectively. Genital Branch The genital branch continues downward on the surface of the psoas major muscle and then enters the inguinal canal through the deep inguinal ring. In men, the genital branch supplies the cremaster and scrotal skin. In women, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anastomosis
An anastomosis (, plural anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf veins, or streams. Such a connection may be normal (such as the foramen ovale in a fetus's heart) or abnormal (such as the patent foramen ovale in an adult's heart); it may be acquired (such as an arteriovenous fistula) or innate (such as the arteriovenous shunt of a metarteriole); and it may be natural (such as the aforementioned examples) or artificial (such as a surgical anastomosis). The reestablishment of an anastomosis that had become blocked is called a reanastomosis. Anastomoses that are abnormal, whether congenital or acquired, are often called fistulas. The term is used in medicine, biology, mycology, geology, and geography. Etymology Anastomosis: medical or Modern Latin, from Greek ἀναστόμωσις, anastomosis, "outlet, opening", Gr ana- "up, on, upon", stoma " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Epigastric Artery
In human anatomy, inferior epigastric artery refers to the artery that arises from the external iliac artery. It anastomoses with the superior epigastric artery. Along its course, it is accompanied by a similarly named vein, the inferior epigastric vein. These epigastric vessels form the lateral border of Hesselbach's triangle, which outlines the area through which direct inguinal hernias protrude. Structure Origin The inferior epigastric artery arises from the external iliac artery, immediately superior to the inguinal ligament. Course and relations It curves forward in the subperitoneal tissue, and then ascends obliquely along the medial margin of the abdominal inguinal ring; continuing its course upward, it pierces the transversalis fascia, and, passing in front of the linea semicircularis, ascends between the rectus abdominis muscle and the posterior lamella of its sheath. It finally divides into numerous branches, which anastomose, above the umbilicus, with th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
