Jump to content

Recommended Posts

  • Replies 44
  • Created
  • Last Reply

Top Posters In This Topic

Posted
In zoological anatomy, a cloaca is the posterior opening that serves as the only such opening for the intestinal, urinary, and (usually) genital tracts of certain animal species. The word comes from Latin, and means "sewer". All birds, reptiles, and amphibians possess this orifice, from which they excrete both urine and feces, unlike placental mammals, which possess two separate orifices for evacuation. Marsupials and monotremes also possess one (in marsupials and a few birds, the genital tract is separate). In contrast, each individual among most species of placental mammals and bony fishes has, in lieu of a cloaca, a specialized opening for at least one of these tracts.

 

In birds the cloaca is also referred to as the vent, and among falconers the word vent is also a verb meaning "to defecate."

 

Excretory systems with analogous purpose in certain invertebrates are also sometimes referred to as "cloacae".

 

One study has looked into birds that use their cloaca for cooling.[1]

 

In birds the reproductive system must be re-engorged prior to the mating season of each species. Such regeneration usually takes about a month. Birds generally produce one batch of eggs per year, but they will produce another if the first is taken away (they have the ability to produce more). For some birds, such as some species of swans and ducks, the males do not use the cloaca for reproduction but have a penis.

 

The cloacal region is also often associated with a secretory organ, the cloacal gland, which has been implicated in the scent marking behavior of some reptiles, amphibians and monotremes.

 

Some turtles, especially those specialized in diving, are highly reliant on cloacal respiration during dives. [2] They accomplish this by having a pair of accessory air bladders connected to the cloaca which can absorb oxygen from the water. [3][4] Sea cucumbers also extract oxygen from water in a pair of 'lungs' or respiratory 'trees' that branch off the cloaca just inside the anus.

 

There are also a variety of fishes, as well as polychaete worms and even crabs, that are specialized to take advantage of the constant flow of water through the cloacal respiratory tree of sea cucumbers while simultaneously gaining the protection of living within the sea cucumber itself. At night many of these species emerge from the anus of the sea cucumber in search of food.

 

:lmao:

Posted

Marsupials have a cloaca that is connected to a urogenital sac in both sexes. Waste is stored there before expulsion. The pregnant female develops a kind of yolk sack in her womb which delivers nutrients to the embryo. The embryo is born at a very early stage of development (at about 4-5 weeks), upon which it crawls up its mother's belly and attaches itself to a nipple (which is located inside the pouch). It remains attached to the nipple for a number of weeks. The offspring later passes through a stage where it temporarily leaves the pouch, returning for warmth and nourishment.

 

;)

 

  • 3 months later...
  • 4 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.




×
×
  • Create New...