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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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foreskin
In male human anatomy, the foreskin, also known as the prepuce, is the double-layered fold of skin, mucosal and muscular tissue at the distal end of the human penis that covers the glans and the urinary meatus. The foreskin is attached to the glans by an elastic band of tissue, known as the frenulum. The outer skin of the foreskin meets with the inner preputial mucosa at the area of the mucocutaneous junction. The foreskin is mobile, fairly stretchable and sustains the glans in a moist environment. Except for humans, a similar structure, known as penile sheath, appears in the male sexual organs of all primates and the vast majority of mammals. In humans, foreskin length varies widely and coverage of the glans in a flaccid and erect state can also vary. The foreskin is fused to the glans at birth and is generally not retractable in infancy and early childhood. Inability to retract the foreskin in childhood should not be considered a problem unless there are other symp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genital Branch Of Genitofemoral Nerve
The genital branch of the genitofemoral nerve, also known as the external spermatic nerve in males, is a nerve in the abdomen that arises from the genitofemoral nerve. The genital branch supplies the cremaster muscle and anterior scrotal skin in males, and the skin of the mons pubis and labia majora in females. Structure The genital branch of the genitofemoral nerve arises from the ventral primary divisions of L1-L2 spinal nerve roots. It passes outward on the psoas major muscle, and pierces the fascia transversalis, or passes through the deep inguinal ring. It then descends within the spermatic cord. In males, it passes through to the scrotum, where it supplies the cremaster, dartos muscle and gives a few filaments to the skin of the scrotum. In females, it accompanies the round ligament of the uterus, where it terminates as the nerve supplying the skin of the labia majora and mons pubis. Function The genital branch of the genitofemoral nerve is responsible for the motor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scrotum
The scrotum or scrotal sac is an anatomical male reproductive structure located at the base of the penis that consists of a suspended dual-chambered sac of skin and smooth muscle. It is present in most terrestrial male mammals. The scrotum contains the external spermatic fascia, testes, epididymis, and ductus deferens. It is a distention of the perineum and carries some abdominal tissues into its cavity including the testicular artery, testicular vein, and pampiniform plexus. The perineal raphe is a small, vertical, slightly raised ridge of scrotal skin under which is found the scrotal septum. It appears as a thin longitudinal line that runs front to back over the entire scrotum. In humans and some other mammals the scrotum becomes covered with pubic hair at puberty. The scrotum will usually tighten during penile erection and when exposed to cold temperatures. One testis is typically lower than the other to avoid compression in the event of an impact. The scrotum is bio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colles Fascia
The membranous layer of the superficial fascia of the perineum (Colles' fascia) is the deeper layer (membranous layer) of the superficial perineal fascia. It is thin, aponeurotic in structure, and of considerable strength, serving to bind down the muscles of the root of the penis. Colles' fascia emerges from the perineal membrane, which divides the base of the penis from the prostate. Colles' fascia emerges from the inferior side of the perineal membrane and continues along the ventral (inferior) penis without covering the scrotum. It separates the skin and subcutaneous fat from the superficial perineal pouch. Relations ''In front'', it is continuous with the dartos fascia of the penis and Scarpa's fascia upon the anterior wall of the abdomen; ''On either side'' it is firmly attached to the margins of the rami of the pubis and ischium, lateral to the crus penis and as far back as the tuberosity of the ischium. ''Posteriorly'', it curves around the superficial transverse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scarpa's Fascia
The fascia of Scarpa is the deep membranous layer ''(stratum membranosum)'' of the superficial fascia of the abdomen. It is a layer of the anterior abdominal wall. It is found ''deep'' to the fascia of Camper and ''superficial'' to the external oblique muscle. Structure It is thinner and more membranous in character than the superficial fascia of Camper, and contains a considerable quantity of orange elastic fibers. It is loosely connected by areolar tissue to the aponeurosis of the external oblique muscle, but in the midline it is more intimately adherent to the linea alba and the pubic symphysis, and is prolonged on to the dorsum of the penis, forming the fundiform ligament; above, it is continuous with the superficial fascia over the rest of the trunk; inferiorly, it is continuous with the fascia of Colles of the perineum; however, it does not extend into the thigh as it just attaches to its fascia, which is known as fascia lata; medially and below, it is continued over the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buck's Fascia
Buck's fascia (deep fascia of the penis, Gallaudet's fascia or fascia of the penis) is a layer of deep fascia covering the three erectile bodies of the penis. Structure Buck's fascia is continuous with the external spermatic fascia in the scrotum and the suspensory ligament of the penis. On its ventral aspect, it splits to envelop corpus spongiosum in a separate compartment from the tunica albuginea and corporal bodies. Variation Sources differ on its proximal extent. Some state that it is a ''continuation'' of the deep perineal fascia, whereas others state that it fuses with the tunica albuginea. Function The deep dorsal vein of the penis, the cavernosal veins of the penis, and the para-arterial veins of the penis are inside Buck's fascia, but the superficial dorsal veins of the penis are in the superficial (dartos) fascia immediately under the skin. History Etymology The name Buck's fascia is named after Gurdon Buck, an American plastic surgeon Plastic surg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatogenesis
Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. This process starts with the mitotic division of the stem cells located close to the basement membrane of the tubules. These cells are called spermatogonial stem cells. The mitotic division of these produces two types of cells. Type A cells replenish the stem cells, and type B cells differentiate into primary spermatocytes. The primary spermatocyte divides meiotically (Meiosis I) into two secondary spermatocytes; each secondary spermatocyte divides into two equal haploid spermatids by Meiosis II. The spermatids are transformed into spermatozoa (sperm) by the process of spermiogenesis. These develop into mature spermatozoa, also known as sperm cells. Thus, the primary spermatocyte gives rise to two cells, the secondary spermatocytes, and the two secondary spermatocytes by their subdivision produce four spermatozoa and four haploid cells. Sperma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testicle
A testicle or testis (plural testes) is the male reproductive gland or gonad in all bilaterians, including humans. It is homologous to the female ovary. The functions of the testes are to produce both sperm and androgens, primarily testosterone. Testosterone release is controlled by the anterior pituitary luteinizing hormone, whereas sperm production is controlled both by the anterior pituitary follicle-stimulating hormone and gonadal testosterone. Structure Appearance Males have two testicles of similar size contained within the scrotum, which is an extension of the abdominal wall. Scrotal asymmetry, in which one testicle extends farther down into the scrotum than the other, is common. This is because of the differences in the vasculature's anatomy. For 85% of men, the right testis hangs lower than the left one. Measurement and volume The volume of the testicle can be estimated by palpating it and comparing it to ellipsoids of known sizes. Another method is to use calip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal Reproductive System
The reproductive system of an organism, also known as the genital system, is the biological system made up of all the anatomical organs involved in sexual reproduction. Many non-living substances such as fluids, hormones, and pheromones are also important accessories to the reproductive system. Unlike most organ systems, the sexes of differentiated species often have significant differences. These differences allow for a combination of genetic material between two individuals, which allows for the possibility of greater genetic fitness of the offspring. Reproductive System 2001 Body Guide powered by Adam Animals In mammals, the major organs of the reproductive system include the external |
Cremasteric Reflex
The cremasteric reflex is a superficial (i.e., close to the skin's surface) reflex observed in human males. This reflex is elicited by lightly stroking or poking the superior and medial (inner) part of the thighâregardless of the direction of stroke. The normal response is an immediate contraction of the cremaster muscle that pulls up the testis ipsilaterally (on the same side of the body). The reflex utilizes sensory and motor fibers from two different nerves. When the inner thigh is stroked, sensory fibers of the ilioinguinal nerve are stimulated. These activate the motor fibers of the genital branch of the genitofemoral nerve which causes the cremaster muscle to contract and elevate the testis. Clinical conditions In boys, this reflex may be exaggerated which can occasionally lead to a misdiagnosis of cryptorchidism. The cremasteric reflex may be absent with testicular torsion, upper and lower motor neuron disorders, as well as a spine injury of L1-L2. It can also occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testis
A testicle or testis (plural testes) is the male reproductive gland or gonad in all bilaterians, including humans. It is homologous to the female ovary. The functions of the testes are to produce both sperm and androgens, primarily testosterone. Testosterone release is controlled by the anterior pituitary luteinizing hormone, whereas sperm production is controlled both by the anterior pituitary follicle-stimulating hormone and gonadal testosterone. Structure Appearance Males have two testicles of similar size contained within the scrotum, which is an extension of the abdominal wall. Scrotal asymmetry, in which one testicle extends farther down into the scrotum than the other, is common. This is because of the differences in the vasculature's anatomy. For 85% of men, the right testis hangs lower than the left one. Measurement and volume The volume of the testicle can be estimated by palpating it and comparing it to ellipsoids of known sizes. Another method is to use cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
