Reproductive system of human beings
Reproductive system of human beings -
Human beings are unisexual and the human reproduction is highly evolved. There is a distinct sexual dimorphism. Thus, the structures associated with reproduction are different in males and females. The structures associated with male reproduction constitutes the male reproductive system. similarly, The structures associated with female reproduction constituted the female reproductive system. The reproductive systems of males and females consists of many organs which are distinguishable into primary and secondary sex organs.
Primary sex organs-
The primary sex organs are gonads, which produce gametes and sacrete sex hormones. The gonads of the male are called testes which produce male gametes- sperms and the male hormone- testosterone . The gonads of the female are ovaries which produce female gamete- ova and female hormones -estrogen and progesterone.
Secondary sex organs-
The secondary sex organs include the genital ducts and glands which help in transportation of gametes and reproductive process. They do not produce gametes or secrete hormones.
Male reproductive system-
Human male reproductive system consists of the following organs-
(1) Testes
(2) Scrotum
(3) Vas Deferens
(4) Urethra
(5) penis
(1) Testes -
The human male possesses to testes, which are the primary reproductive organs, lying outside the abdominal cavity. The two testes are the male gonads, which are the sites where male gametes (sperms) are made. The tastes also produce the male sex hormone- testosteron. The testes of man produce sperms from puberty onwards, throughout his life.
(2) Scrotum-
The scrotum is a pouch of skin that hangs between the legs. It is divided internally into right and left scrotal sacs by a muscular partition. The two tastes lie in respective scrotal sacs. The scrotum acts as a thermoregulator and provides an optimal temperature for the formation of sperms. The sperms develop at a temperature 1-3°C lower than the normal body temperature. The life of sperms is greatly reduced if the temperature is higher. During winters when temperature falls the scrotum shrinks to bring the testes close to body to get warmth. During summers when temperature rises the scrotum becomes relaxed to loss heat.
(3) Vas deferens -
This is a straight tube about 40 cm long which carries the sperms to the seminal vesicles. The sperms are stored temporally in the seminal vesicle where mucus and a watery alkaline fluid containing the sugar fructose mix with the the sperms.
(4) Urethra-
It is about 20 cm long tube that arises from the urinary bladder to carry urine. It runs through the penis and opens to the outside from male genital pore. The contents of two seminal vesicles sperm from was difference also join the urethra. Thus urethra carries urine from the bladder as well as sperms from the Vas diferentia through the penis.
(5) Penis-
Penis is a long and thick muscular organ made up of mostly erectile tissue. The tip of penis consists of a soft and highly sensitive glans penis which is covered by a loose retractable fold of skin called foreskin. At the time of sexual excitement the erectile tissue gets filled with blood causing the penis to become erect. It is inserted into the vagina of the female where sperms are ejaculated for the purpose of reproduction.
In human males there is only one opening for the urine and sperms to pass out of body.
Female reproductive system-
Female reproductive system is more complex as compared to that of males. The complexity of sexual structures in females is due to the fact that it accepts sperm from male, supports their movement up to egg, fertilization and subsequent post fertilization changes. Female reproductive system consists of the following organs.
(1) Ovaries
(2) Fallopian tubes (oviduct)
(3) Uterus
(4) Vagina
(1) Ovaries -
Each human female contains two almond shaped ovaries located in the lower part of abdominal cavity near the kidney. Each ovary is connected by a ligament to the uterus. The ovaries are primary sex organs (or female gonads) which perform the dual function - (a)production of female gametes (eggs or ova) and (b) secretion of female sex hormones (estrogen and progesterone. Each ovary is composed of ovarian follicles at various stages of development. Each follicle contains a large ovum surrounded by many layers of follicle cells. The production of ova starts at the age of puberty. Usually one ovum is produced every month during the fertile years of a woman. After menopause the ovaries become small and loss follicle.
(2) Fallopian tubes (oviduct)-
A fallopian tube is about 10 to 12 cm long muscular tube which carries egg from the ovary to the uterus and also provides the appropriate environment for its fertilization. The funnel shaped opening end of each fallopian tube lies near the posterior ends of each ovary. The other ends of the long convoluted tubes open into the uterus.
(3) Uterus-
The uterus is a large inverted pear-shaped muscular structure that lies behind the bladder. If fertilization takes place the embryo gets attached to the wall of uterus and grows there until birth.
(4) Vagina -
This is a muscular tube about 7 to 10 cm long whose walls contain elastic tissue. It is well adapted to receive the male's penis during copulation. The vagina is also called birth canal as it allows passage of the baby at the time of childbirth.
In human females the urinary opening (external opening of urethra) and vaginal openings are separate.
Human beings are unisexual and the human reproduction is highly evolved. There is a distinct sexual dimorphism. Thus, the structures associated with reproduction are different in males and females. The structures associated with male reproduction constitutes the male reproductive system. similarly, The structures associated with female reproduction constituted the female reproductive system. The reproductive systems of males and females consists of many organs which are distinguishable into primary and secondary sex organs.
Primary sex organs-
The primary sex organs are gonads, which produce gametes and sacrete sex hormones. The gonads of the male are called testes which produce male gametes- sperms and the male hormone- testosterone . The gonads of the female are ovaries which produce female gamete- ova and female hormones -estrogen and progesterone.
Secondary sex organs-
The secondary sex organs include the genital ducts and glands which help in transportation of gametes and reproductive process. They do not produce gametes or secrete hormones.
Male reproductive system-
Human male reproductive system consists of the following organs-
(1) Testes
(2) Scrotum
(3) Vas Deferens
(4) Urethra
(5) penis
(1) Testes -
The human male possesses to testes, which are the primary reproductive organs, lying outside the abdominal cavity. The two testes are the male gonads, which are the sites where male gametes (sperms) are made. The tastes also produce the male sex hormone- testosteron. The testes of man produce sperms from puberty onwards, throughout his life.
(2) Scrotum-
The scrotum is a pouch of skin that hangs between the legs. It is divided internally into right and left scrotal sacs by a muscular partition. The two tastes lie in respective scrotal sacs. The scrotum acts as a thermoregulator and provides an optimal temperature for the formation of sperms. The sperms develop at a temperature 1-3°C lower than the normal body temperature. The life of sperms is greatly reduced if the temperature is higher. During winters when temperature falls the scrotum shrinks to bring the testes close to body to get warmth. During summers when temperature rises the scrotum becomes relaxed to loss heat.
(3) Vas deferens -
This is a straight tube about 40 cm long which carries the sperms to the seminal vesicles. The sperms are stored temporally in the seminal vesicle where mucus and a watery alkaline fluid containing the sugar fructose mix with the the sperms.
(4) Urethra-
It is about 20 cm long tube that arises from the urinary bladder to carry urine. It runs through the penis and opens to the outside from male genital pore. The contents of two seminal vesicles sperm from was difference also join the urethra. Thus urethra carries urine from the bladder as well as sperms from the Vas diferentia through the penis.
(5) Penis-
Penis is a long and thick muscular organ made up of mostly erectile tissue. The tip of penis consists of a soft and highly sensitive glans penis which is covered by a loose retractable fold of skin called foreskin. At the time of sexual excitement the erectile tissue gets filled with blood causing the penis to become erect. It is inserted into the vagina of the female where sperms are ejaculated for the purpose of reproduction.
In human males there is only one opening for the urine and sperms to pass out of body.
Female reproductive system-
Female reproductive system is more complex as compared to that of males. The complexity of sexual structures in females is due to the fact that it accepts sperm from male, supports their movement up to egg, fertilization and subsequent post fertilization changes. Female reproductive system consists of the following organs.
(1) Ovaries
(2) Fallopian tubes (oviduct)
(3) Uterus
(4) Vagina
(1) Ovaries -
Each human female contains two almond shaped ovaries located in the lower part of abdominal cavity near the kidney. Each ovary is connected by a ligament to the uterus. The ovaries are primary sex organs (or female gonads) which perform the dual function - (a)production of female gametes (eggs or ova) and (b) secretion of female sex hormones (estrogen and progesterone. Each ovary is composed of ovarian follicles at various stages of development. Each follicle contains a large ovum surrounded by many layers of follicle cells. The production of ova starts at the age of puberty. Usually one ovum is produced every month during the fertile years of a woman. After menopause the ovaries become small and loss follicle.
(2) Fallopian tubes (oviduct)-
A fallopian tube is about 10 to 12 cm long muscular tube which carries egg from the ovary to the uterus and also provides the appropriate environment for its fertilization. The funnel shaped opening end of each fallopian tube lies near the posterior ends of each ovary. The other ends of the long convoluted tubes open into the uterus.
(3) Uterus-
The uterus is a large inverted pear-shaped muscular structure that lies behind the bladder. If fertilization takes place the embryo gets attached to the wall of uterus and grows there until birth.
(4) Vagina -
This is a muscular tube about 7 to 10 cm long whose walls contain elastic tissue. It is well adapted to receive the male's penis during copulation. The vagina is also called birth canal as it allows passage of the baby at the time of childbirth.
In human females the urinary opening (external opening of urethra) and vaginal openings are separate.
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