Urethra, duct that transmits urine from the bladder to the exterior of the body during urination. The urethra is held closed by the urethral sphincter, a muscular structure that helps keep urine in the bladder until voiding can occur. Organs of the renal system. Encyclopædia Britannica, Inc.
What is the urethra?
In anatomy, the urethra (from Greek ο?ρήθρα – our?thrā) is a tube that connects the urinary bladder to the urinary meatus for the removal of urine from the body. In males, the urethra travels through the penis and also carries semen. Only in the male is there an additional internal urethral sphincter muscle.
What is the structure and function of the bladder?
The urinary bladder is a muscular sac in the pelvis, just above and behind the pubic bone. When empty, the bladder is about the size and shape of a pear. Urine is made in the kidneys and travels down two tubes called ureters to the bladder. The bladder stores urine, allowing urination to be infrequent and controlled.
What is the role of the urethra?
Urethra: The urethra is the tube that carries urine from the bladder to outside of the body. In males, it has the additional function of ejaculating semen when the man reaches orgasm. When the penis is erect during sex, the flow of urine is blocked from the urethra, allowing only semen to be ejaculated at orgasm.
What is the basic structural and functional unit of the kidney?
The nephron (from Greek νεφρός – nephros, meaning “kidney”) is the microscopic structural and functional unit of the kidney. It is composed of a renal corpuscle and a renal tubule. The renal corpuscle consists of a tuft of capillaries called a glomerulus and an encompassing Bowman’s capsule.
What is the function of the kidneys?
maintaining overall fluid balance. regulating and filtering minerals from blood. filtering waste materials from food, medications, and toxic substances. creating hormones that help produce red blood cells, promote bone health, and regulate blood pressure.
What are the causes of urethritis?
The herpes simplex virus (HSV-1 and HSV-2) can also cause urethritis. Trichomonas is another cause of urethritis. It is a single-celled organism that is sexually transmitted. Sexually transmitted infections like gonorrhea and chlamydia are usually confined to the urethra.
How does the urethra work?
The organs, tubes, muscles, and nerves that work together to create, store, and carry urine are the urinary system. The urinary system includes two kidneys, two ureters, the bladder, two sphincter muscles, and the urethra.
What is a female urethral opening?
Urethral opening, female: The urethra is the transport tube leading from the bladder to discharge urine outside the body. In females the urethra is shorter than in the male and opens above the vaginal opening, as indicated here: Impotence Slideshow Pictures.
What is the function of the ureter?
The ureters are narrow, hollow, muscular tubes, approximately nine inches long, that connect the kidneys to the bladder. Each kidney has its own ureter through which urine passes. Urine does not flow in a slow, steady stream along the length of the ureters into the bladder.
What are the main functions of the urinary system?
Their function is to remove liquid waste from the blood in the form of urine; keep a stable balance of salts and other substances in the blood; and produce erythropoietin, a hormone that aids the formation of red blood cells. The kidneys remove urea from the blood through tiny filtering units called nephrons.
What is the function of the prostate gland?
The prostate gland is a male reproductive organ whose main function is to secrete prostate fluid, one of the components of semen. The muscles of the prostate gland also help propel this seminal fluid into the urethra during ejaculation .
Where does the urine come out of a woman?
Fortunately, there is an easy answer to your question: Neither! Urine exits from a separate body part called the urethra, or the tube that carries urine from the bladder to the urethral opening. The urethral opening is the hole that is below the clitoris and above the vaginal opening.
How common is urethral cancer?
Urethral cancer is a disease in which malignant (cancer) cells form in the tissues of the urethra. The urethra is the tube that carries urine from the bladder to outside the body. Urethral cancer is a rare cancer that occurs more often in men than in women.
What is urine tract infection?
A urinary tract infection (UTI) is an infection involving the kidneys, ureters, bladder, or urethra. These are the structures that urine passes through before being eliminated from the body. The kidneys are a pair of small organs that lie on either side of the spine at about waist level.
Which organs form urine?
kidneys: two bean-shaped organs that filter waste from the blood and produce urine. ureters: two thin tubes that take pee from the kidney to the bladder.
Is the urethra and organ?
The urethra is also an organ of the male reproductive system as it carries sperm out of the body through the penis. The flow of urine through the urethra is controlled by the internal and external urethral sphincter muscles.
How is urine formed in the human body?
Urine is formed in the kidneys through a filtration of blood. The urine is then passed through the ureters to the bladder, where it is stored. During urination, the urine is passed from the bladder through the urethra to the outside of the body. This amount varies according to fluid intake and kidney function.
What triggers the urinary reflex?
The state of the reflex system is dependent on both a conscious signal from the brain and the firing rate of sensory fibers from the bladder and urethra. During micturition, parasympathetic stimulation causes the detrusor muscle to contract and the internal urethral sphincter to relax.
What is stricture of the urethra?
A urethral stricture is a narrowing of the urethra caused by injury, instrumentation, infection and certain non-infectious forms of urethritis.
What is the role of the skin in excretion?
The skin contains sweat glands that excrete perspiration through skin pores. Perspiration is made up of nitrogenous wastes (urea), salts, and water. The skin is also involved in controlling body temperature. The lungs also play a role in excretion.
Where is the Calyces located?
Renal calyx. Kidney, with major and minor calyces labeled near bottom. The renal calyces are chambers of the kidney through which urine passes. The minor calyces surround the apex of the renal pyramids.
What type of muscle is the bladder?
Detrusor muscle. The detrusor muscle is a layer of the urinary bladder wall made of smooth muscle fibers arranged in spiral, longitudinal, and circular bundles.