Gonad
A gonad or sex gland or reproductive gland is an endocrine gland that produces the gametes (germ cells) of an organism. In the female of the species the reproductive cells are the egg cells, and in the male the reproductive cells are the sperm. The male gonad, the testicle, produces sperm in the form of spermatozoa. The female gonad, the ovary, produces egg cells. Both of these gametes, are haploid germ cells.
Regulation
The gonads are controlled by luteinizing hormone and follicle-stimulating hormone, produced and secreted by gonadotropes in the anterior pituitary gland. This secretion is regulated by gonadotropin-releasing hormone produced in the hypothalamus.
Development
Gonads start developing as a common primordium (an organ in the earliest stage of development), in the form of gonadal ridges, and only later are differentiated to male or female sex organs. The presence of the SRY gene, located on the Y chromosome and encoding the testis determining factor, determines male sexual differentiation. In the absence of the SRY gene from the Y chromosome, the female sex (ovaries instead of testes) will develop. The development of the gonads is a part of the development of the urinary and reproductive organs.
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When The Raven Flies
by: CountessWhen summers are forgotten
And brothers slay each other
When the legions of Surt rise
And Muspell´s horde fills the skies
When the Norns annihilate all peace
And Naglfar sails the seas
The dawn of the final war is here
When gods wage war the end is near
When the horn of Heimdall blows
And holy blood in thick rivers flows
When the son of Loki breaks his chains
And Midgard is consumed by flames
When forces of darkness and light collide
For puny mortals there´ll be nowhere to hide
The dawn of the final war is here
When gods wage war the end is near
When the raven flies
We must heed the call
When the raven flies
We will stand or fall
When the raven flies
We must heed the call
When the raven flies
We will stand or fall
When the sky turns black as night
And nothing is left but the will to fight
When the Einherjar are to fulfill their destiny
There´s no more use for All-Father's necromancy
When giants and trolls united ride
And even Wodan and Donar fall side by side
The dawn of the final war is near
When gods wage war the end is here