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A complex placenta. Marsupials have a choriovitelline placenta, but it is not as well-developed as the placentas of placental mammals.
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Why are some mammals that lay eggs classified as mammals?
Monotremes lay eggs, as do reptiles. Monotremes' limbs go outward (rather than downward) from their main body, which is also true for reptiles. Monotremes lack a corpus callosum (which placental mammals have), as do reptiles. Monotremes and reptiles both have cloacas, while placental mammals have separate openings for urination and defecation. This evidence all shows monotremes to be a link between reptiles and mammals, but we now think that monotremes just evolved from an earlier branching from the mammalian tree of lineage than the marsupials and placental mammals evolved from. Monotremes are not a link between reptiles and mammals.
What organ systems do Echinoderms lack?
What organ systems do echinodermes lacking
Do monotrems have mammary glands?
Yes. Monotremes are mammals, so they have mammary glands. What they lack, however, is developed teats for the young babies to suckle. These animals do not suckle their young quite like other mammals do. They do not have nipples, but exude milk from specialised sweat glands on their abdomen.
Lack of development of an organ or tissue?
aplasia
Which organ does a deer lack?
Deer do not have a gallbladder. Scientists have still not been able to establish why they lack this organ that's responsible for producing bile that aids in digestion.
Why are monotremes found in austrillia?
Monotremes were among the earliest mammals to evolve. However, in most of the world, all monotremes went extinct as a result of competition with more advanced placental mammals. Australia and New Guinea, however, have been so isolated that there were nearly no placental mammals (except for bats) until humans introduced them. The lack of competition from placental mammals allowed monotremes to survive in Australia.
Can transmen get pregnant?
No, they cannot, they lack the required organs to become pregnant.
What is the difference between aplasia and agenesis?
Aplasia is the absence of the organ with only the rudiment present Agenesis is the complete lack of the organ
Which organelle seperates eukaryote from prokaryote?
It is the nucleus .Prokariyotes lack a nucleus.
The incomplete development of an organ due to a deficiency in the number of cells is known as?
Aplasia is the lack of normal development of a tissue or organ.
Which marsupials lack a forked penis?
Big Red Kangaroo, Western Grey Kangaroo, Eastern Grey Kangaroo, Whiptail Wallaby, Honey Possum
Can you get pregnant if you have clothes on and you lay on top of a boy and you kiss but he doesnt ejaculate?
No. With clothes as a barrier and his lack of ejaculation, you will not get pregnant.
