Reproductive system

system of organs within an organism which work together for the purpose of reproduction

The placenta (: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas, and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ, producing hormones that regulate both maternal and fetal physiology during pregnancy. The placenta connects to the fetus via the umbilical cord, and on the opposite aspect to the maternal uterus in a species-dependent manner. In humans, a thin layer of maternal deci

A gamete ( ), reproductive cell, or sex cell, is a haploid cell that fuses with another haploid cell during fertilization in organisms that reproduce sexually. The name gamete was introduced by the German cytologist Eduard Strasburger in 1878.

300px|thumb|Cornu aspersum|Garden snails mating A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic.

Sperm (: sperm or sperms) is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Sperm cells contribute approximately half of the nuclear genetic information to the diploid offspring (excluding, in most cases, mitochondrial DNA). Animals produce motile sperm with a tail known as a flagellum, which are known as spermatozoa, while some red algae and fungi produce non-motile sperm cells, known as spermatia. Flowering plants contain non-motile sperm inside pollen, while some more ba

Hysterectomy is the surgical removal of the uterus and cervix. Supracervical hysterectomy refers to the removal of the uterus while the cervix is spared. These procedures may also involve removal of the ovaries (oophorectomy), fallopian tubes (salpingectomy), and other surrounding structures. The terms "partial" or "total" hysterectomy are lay terms that incorrectly describe the addition or omission of oophorectomy at the time of hysterectomy. These procedures are usually performed by a gynecologist. Removal of the uterus is a form of sterilization, rendering the patient unable to bear childre

Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes. Depending on the biological life cycle of the organism, gametogenesis occurs by meiotic division of diploid gametocytes into various gametes, or by mitosis. For example, plants produce gametes through mitosis in gametophytes. The gametophytes grow from haploid spores after sporic meiosis. The existence of a multicellular, haploid phase in the life cycle between meiosis and gametogenesis is also referred to as alternation of generations.

Vaginoplasty is any surgical procedure that results in the construction or reconstruction of the vagina. It is a type of genitoplasty. Pelvic organ prolapse is often treated with one or more surgeries to repair the vagina. Sometimes a vaginoplasty is needed following the treatment or removal of malignant growths or abscesses to restore a normal vaginal structure and function. Surgery to the vagina is done to correct congenital defects to the vagina, urethra and rectum. It may correct protrusion of the urinary bladder into the vagina (cystocele) and protrusion of the rectum (rectocele) into the

Dioecy (; adj. dioecious) is a characteristic of certain species that have distinct unisexual individuals, each producing either male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is biparental reproduction. Dioecy has costs, since only the female part of the population directly produces offspring. It is one method for excluding self-fertilization and promoting allogamy (outcrossing), and thus tends to reduce the expression of recessive deleterious mutations present in a population. Plants have several other methods of preventing self-fe

organs involved in human reproduction

thumb|200px|A cystocele protruding through the vagina in a 73-year-old woman A cystocele, also known as a prolapsed bladder, is a medical condition in which a woman's bladder bulges into her vagina. Some may have no symptoms. Others may have trouble starting urination, urinary incontinence, or frequent urination. Complications may include recurrent urinary tract infections and urinary retention. Cystocele and a prolapsed urethra often occur together and is called a cystourethrocele. Cystocele can negatively affect quality of life.

glycoprotein layer surrounding the plasma membrane of mammalian oocytes

thumb|Oogamy in animals: small, motile sperm on the surface of an ovum

thumb|Light micrograph of a whole-mount slide of gametangia of [[Equisetum]] A gametangium (: gametangia) is a sex organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants. In contrast to gametogenesis in animals, a gametangium is a haploid structure and formation of gametes does not involve meiosis.

The spermatid is the haploid male gametid that results from division of secondary spermatocytes. As a result of meiosis, each spermatid contains only half of the genetic material present in the original primary spermatocyte.

species of bacterium

one of the late complications of pelvic inflammatory disease

phase of the estrous cycle, (or, in humans and great apes, the menstrual cycle) during which follicles in the ovary mature (it ends with ovulation, the main hormone controlling this stage is estradiol)

thumb|Close up of aecia of Puccinia sessilisAn aecium (plural aecia) is a specialised reproductive structure found in some plant pathogenic rust fungi that produce aeciospores. Aecia may also be referred to as "cluster cups". The term aecidium (plural aecidia) is used interchangeably but is not preferred.

species of bacterium

species of bacterium

biological process that prevents polyspermy

Trioecy is a sexual system characterized by the coexistence of males, females, and hermaphrodites. It has been found in both plants and animals. Like androdioecy and gynodioecy, trioecy is a mixed mating systems.

Sporogenesis is the production of spores in biology. The term is also used to refer to the process of reproduction via spores. Reproductive spores were found to be formed in eukaryotic organisms, such as plants, algae and fungi, during their normal reproductive life cycle. Dormant spores are formed, for example by certain fungi and algae, primarily in response to unfavorable growing conditions. Most eukaryotic spores are haploid and form through cell division, though some types are diploids or dikaryons and form through cell fusion.

species of bacterium