well, The male reproductive organ involved in sexual intercourse and elimination of urine. It is an external sexual organ of certain biologically male organisms. The penis is a reproductive organ, technically an intromittent organ, and for placental mammals, additionally serves as the external organ of urination.

Answered by Satya ~ , an ibibo Master, at 11:42 PM on September 24, 2008

The penis is an external sexual organ of certain biologically male organisms. The penis is a reproductive organ, technically an intromittent organ, and for placental mammals, additionally serves as the external organ of urination. The penis is generally found on mammals and reptiles.

Answered by pankaj , an ibibo Advisor, at 12:52 PM on September 20, 2008

The penis is an external sexual organ of certain biologically male organisms. The penis is a reproductive organ, technically an intromittent organ, and for placental mammals, additionally serves as the external organ of urination. The penis is generally found on mammals and reptiles.

Answered by alok , an ibibo Master, at 12:49 PM on September 20, 2008

The Penis
The penis is made up of spongy erectile tissue, which fills with blood when a man is turned on or aroused and usually becomes erect. Penises come in all sizes, and penis size in almost all cases has nothing to do with how a penis works or how well a penis works. There are several different parts to the penis, each of which has some impact on feeling sexual arousal and pleasure.
The results from three studies of penis size where the measurements were taken in a laboratory setting give the following ranges:

Average penis length (flaccid/not erect): (8.6 cm to 9.3 cm)
Average penis length (erect): (12.9 cm to 14.5 cm)

Answered by SESHAN , an ibibo Master, at 10:55 AM on September 20, 2008

penis is the erectile organ in males..
it has three muscles anatomically, all of which have individual large venous drainage..
when person gets excited there is vagal discharge which causes vasodilatation which means veins gets dilated and accomodates more blood..,
causes stiffening of penis and thus erection..

there is urethra[passage] in centre of penis which passes urine and also semen during ejaculation[during sexual intercourse]

Answered by Alok Rathi , an ibibo Citizen, at 8:15 PM on September 19, 2008

well,The penis of the Arachnida is an intromitent organ, present exclusively in the order Opiliones. It consists of a long shaft, the truncus, and a terminal capsule called glans, containing the stylus and ejaculatory duct. It may have from one to three muscles, or none in the specialized lineage Grassatores, where the penis is operated by haemolymph pressure.

This denomination refers to a superficial similarity (analogy) with vertebrate penises and does not have any phylogenetic relationship with it

source;en.wikipedia.org/ wiki/Penis (Arachnida)

Answered by Debashis , an ibibo Master, at 7:25 PM on September 19, 2008