Search results
Results From The WOW.Com Content Network
Germ cells are specified early in development [4] and can only differentiate into gametes. [5] The segregation of germ cells is often determined by the species, with some undergoing preformation, where the germ cells are determined by maternally inherited factors before or immediately after fertilisation, and others undergoing epigenesis, where the germ cell lineage is determined from ...
A gonad, sex gland, or reproductive gland [1] is a mixed gland and sex organ that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. [2] The male gonad, the testicle, produces sperm in the form of spermatozoa. The female gonad, the ovary, produces egg cells
Somatic cells are more commonly used for genetic analysis because they are easier to obtain than gametes. If the disease is a result of pure germline mosaicism, then the disease causing mutant allele would never be present in the somatic cells. This is a source of uncertainty for genetic counselling. An individual may still be a carrier for a ...
Cormlets of Watsonia meriana, an example of apomixis Clathria tuberosa, an example of a sponge that can grow indefinitely from somatic tissue and reconstitute itself from totipotent separated somatic cells. In biology and genetics, the germline is the population of a multicellular organism's cells that develop into germ cells.
The reproductive system begins development at four to five weeks of gestation with germ cell migration. The bipotential gonad results from the collection of the medioventral region of the urogenital ridge. At the five-week point, the developing gonads break away from the adrenal primordium. Gonadal differentiation begins 42 days following ...
Cleavage in most animals segregates cells containing germ plasm from other cells. The germ plasm effectively turns off gene expression to render the genome of the cell inert. Cells expressing germ plasm become primordial germ cells (PGCs) which will then give rise to the gametes. The germ line development in mammals, on the other hand, occurs ...
Germ cells migrating to the gonads may not reach that intended destination and a tumor can grow wherever they end up, but the exact cause is still unknown. These tumors can be benign or malignant. [23] On arrival at the gonad, primordial germ cells that do not properly differentiate may produce germ cell tumors of the ovary or testis in a mouse ...
2 and 5 sex cords A depiction of the migration of the cells which will give rise to the sex cords into the genital ridge where they will become the gonads of the embryo. Sex cords are embryonic structures which eventually will give rise (differentiate) to the adult gonads (reproductive organs). [1]