Urogenital System

Introduction

The term urogenital refers to merging the urinary and reproductive systems in males. These are classified together due to their close vicinity, same embryological origins, and use of common channels, such as the male urethra. The systems are also sometimes projected together due to their tight proximity.

The epididymis, testes, vas deferens, ejaculatory ducts, penis, urethra, prostate, and accessory glands are all elements of the male urogenital system.

Table of Contents

• Meaning of Urinogenital
  • Urinogenital Duct
• Male and Female Excretory System
• Development of Urogenital System
  • Male Urogenital System
  • Female Urogenital System
• Significance of Urogenital System
• Frequently Asked Questions (FAQs)

Meaning of Urinogenital

Urinogenital refers to or is associated with the genital and urinary organs. The urinogenital or urogenital system is made up of the urinary and genital organs and their associated structures that grow in the foetus to create kidneys, bladder, ureters, urethra, and genital tissues in both men and females.

The female reproductive organs are the ovaries, uterus, clitoris, uterine tubes, and vagina. The male reproductive organs are the seminal vesicles, testes, seminal ducts, prostate, and penis.

Urinogenital Duct

The urethra in males is also known as the urinogenital duct.

• Urinogenital duct refers to the duct that transports both urine and genital products.
• The urethra is lodged across the length of the penis in males, via which urine and sperm are eliminated from the body during urination and coitus, respectively.
• The urogenital duct refers to the passage of urine (from the urinary system) and sperm (from the reproductive system) through the urethra.

Read more: Urogenital tract

Male and Female Excretory System

Males and females have identical Kidneys structure, ureters structures, bladder anatomy, and urethra structure. With the exception of the vas deferens, most sex differences in the urinary system originate at the bladder neck and extend distally.

• Kidneys are the principal excretory organs in humans, and they act in conjunction with auxiliary organs such as the lungs, gills, skin, digestive system, and salt glands. The kidneys develop from lateral plate mesoderm, which buds into nephric ridges, differentiating into nephrotomes, which further differentiate into nephrons or renal tubules, the kidney’s structural and functional units.
• Urine is carried from the kidneys to the bladder through the ureters. The ureters are a feature of the urinary system that filters blood and produces urine. Smooth muscle contracts in the ureteral tubes to transport urine from the kidneys to the bladder.
• Urine is temporarily stored in the urinary bladder. Because the uric acid excreted in reptiles and birds is semisolid, the urethra empties it immediately into the cloaca. The bladder in mammals is typically large and coated with epithelium and muscle cells.
• The urethra is a tubular organ that transports urine from the bladder to the prostate and out of the penis. Males’ urethras are significantly longer than females’, measuring 17-20 cm and 2.5-4 cm, respectively. The membranous urethra, the prostatic urethra, the bulbar urethra, and the pendulous (or penile) urethra are the four portions of the male urethra, which are discussed in the Urethral Anatomy article.

Development of Urogenital System

• The urogenital system is formed by intermediate mesoderm that generates a urogenital ridge on both sides of the aorta.
• The pronephros, mesonephros, and metanephros are three tubular nephric structures that emerge from the urogenital ridge (from head to tail).
• The pronephros is the cranial most pair of tubes, and it relapses most of the time.
• The mesonephros evolves into mesonephric tubules and the mesonephric duct along the midsection of the embryo (Wolffian duct). Initially, these tubules perform some kidney function, but then many of them retreat. The mesonephric duct, on the other hand, remains and connects to the cloaca at the embryo’s tail.
• The metanephros provides production to the adult kidney in its final form. The metanephric blastema develops from the condensation of adjacent neurogenic intermediate mesoderm and an extension of the caudal mesonephric duct, the ureteric bud.

Male Urogenital System

The testes, epididymis, ejaculatory ducts, vas deferens, urethra, penis, prostate, and accessory glands are all elements of the male urogenital system.

Testes

Within the scrotum, the testis is a solid, mobile organ; the left testis is slightly lower than the right one. The testes are the male’s major reproductive organs (gonads), and they are in charge of producing sperm.

Sertoli cells and Leydig cells are two major significant functioning components of the testis. The production of testosterone is controlled by the Leydig cells in the testis, which are essentially non-existent before puberty.

Epididymis

The epididymis is a solid structure with three parts: an extended head, a body, and a tail. It’s about 20 metres long when fully inflated. The vas deferens develop from the epididymis’ tail.

After developing in the seminiferous tubules, sperm enter the epididymis. After 18–24 hours in the epididymis, these non-motile sperm develop the ability to move; however, the creation of certain chemicals within the epididymis prevents their real movement.

Vas deferens

The vas deferens is a muscular tube that delivers sperm to the ejaculatory ducts and is 45 cm long.

Ejaculatory Ducts

The vas deferens connects the ducts emerging from the seminal vesicles on either side to generate the two ejaculatory ducts. They are about 2 cm long and enter the prostate gland exiting into the urethra that passes through the prostate.

Urethra

The male urethra is 18–20 cm long, extending from the internal opening of the urinary bladder to the external urethral orifice at the penis end. Urine and sperm can pass through the urethra.

Penis

The penis is the male external genitalia. The root and body are the two primary elements of the penis. Separate nerve responses to the penis control ejaculation. The vas deferens contracts as a result of nerve signals. The prostate gland and seminal vesicles also contract at this point, releasing their fluids into the sperm.

Prostate Gland

The fibromuscular prostate gland surrounds the prostatic section of the urethra. Citrate ions, phosphate ions, and enzymes are the main elements of the thin milky fluid produced by the prostate gland. The prostatic fluid is kind of basic, which is important because sperm fertility is inhibited in an acidic environment.

Accessory Glands

Seminal vesicles and Bulbourethral glands are the accessory glands of the male urogenital system. The bulbourethral glands secrete a lubricant that aids in the lubrication of the penis head during erection and ejaculation.

Female Urogenital System

All of the organs involved in reproduction, as well as the generation and release of urine, comprise the female urogenital system. The kidneys, bladder, ureters, urethra, and reproductive organs (ovaries, uterus, fallopian tubes, and vagina) are all part of this system.

The kidneys are bean-shaped organs that help in the production of urine, which helps the body cleanse itself of undesirable waste. Urine is generated and transported to the urinary bladder by tubes called ureters, where it is stored and excreted through the urethra.

The cervix of one end of the uterus opens into the vaginal canal, while the other end is attached to the fallopian tubes on both sides.

Fallopian Tubes

Fine tubes connecting the ovaries to the uterus are known as fallopian tubes. They play a crucial role in the transmission of eggs from the ovary to the uterus. This procedure is required for fertilisation and the baby’s early development.

Ovary

Females have two ovaries, which are primarily responsible for producing eggs and secreting hormones (oestrogen and progesterone). These ovaries are connected to the uterus by specific ligaments (tough tissue sheets). The ovary receives its blood supply through blood vessels known as ovarian arteries.

Vagina

The vagina is a 6-7.5 cm long muscular tube that connects the uterus to the outside environment. Copulation, enabling menstrual blood to exit the system, and giving birth are all functions of the vagina.

Significance of Urogenital System

The urogenital system is in charge of urine production, storage, and elimination, as well as reproductive activity. Autonomic (parasympathetic and sympathetic) and somatic efferent pathways arising in the lumbosacral spinal cord govern many urogenital activities.

Some urogenital functions, such as penile erection, are completely automatic and controlled by reflex circuits in the spinal cord or brain stem, whereas others, such as micturition, are more sophisticated and require intentional control by the cerebral cortex.

Bilateral renal agenesis, bladder agenesis, and full vulvar opening aplasia are examples of urogenital system defects that can be fatal (if not detected early). In males, uncertain sexual delineation and hypospadias are two further defects that can be observed in crias (a baby llama).

Further Reading:

• Human Excretory System
• Excretory Products and their Elimination
• Human Reproductive System
• Female Reproductive System
• Male Reproductive System