2006-10-13 09:16:49 · 21 answers · asked by bevan c 1 in Science & Mathematics ➔ Biology
No.
There are a class of mammals called "egg laying" mammals that do not have umbilical cords. These include the Platypus, spinney anteater, and others. They still have a single bone in their lower jaw, three middle ear bones, high metabolic rates, hair, and they produce milk to nourish the young, all characteristics of mammals, so they are classified as mammals. But since their young come out of an egg, and are nourished by the egg (and not the mother), there's no umbilical cord.
Marsupials do not have umbilical cords either.
2006-10-13 09:22:38 · answer #1 · answered by ZenPenguin 7 · 6⤊ 0⤋
Only female, non-egg laying mammals have umbilical cords. Marsupials do have umbilical cords but due to an extremely short gestation cycle, they break off from the infant..
2006-10-14 10:27:34 · answer #2 · answered by Andrew W 4 · 0⤊ 0⤋
YES all developed in a womb therefore need a umbilical cord to transfer food to baby
2006-10-13 10:07:34 · answer #3 · answered by Greenman 2 · 0⤊ 2⤋
No, marsupials are non-placental mammals, like kangaroos that grow their young in pouches. Additionally, a few mammals like the platypus and spiny anteater actually lay leathery eggs, although they are fertilized internally.
2006-10-13 09:55:00 · answer #4 · answered by pdigoe 4 · 2⤊ 0⤋
Yes, and belly buttons of some variety. Being a mammal is defined, in part, by live birth (which requires an umbilical cord.) Once the baby is born, it requires nourishment from the mother (from her mammary glands - hence mammals.)
2006-10-13 09:25:45 · answer #5 · answered by tigglys 6 · 0⤊ 5⤋
no only placentals (mammals with a placenta).
marsupials have a pouch and monetremes of which there are only 2-3 (all are in australia) species lay eggs.
2006-10-13 09:25:16 · answer #6 · answered by ui6fu6yujt c 2 · 4⤊ 0⤋
no- the platypus is technically a mammal because it is nursed by its mother (drinks milk) from birth. However, the platypus is hatched from an egg!
2006-10-13 09:45:42 · answer #7 · answered by amesbh 2 · 2⤊ 0⤋
Yes all mammals have umbilical cords but they are so old fashioned I imagine they would prefer jeans
2006-10-13 09:22:49 · answer #8 · answered by SAMUEL M 1 · 0⤊ 5⤋
Yes. Although Echidnas and Duck Billed Platypuses (Platypii?), lay eggs, the young are still attached to the yolk sack by an umbilical cord.
2006-10-13 09:25:04 · answer #9 · answered by Anonymous · 0⤊ 5⤋
No, I believe marsupials, ie, animals with pouches, like kangaroos, etc. are mammals, also.
2006-10-13 09:26:28 · answer #10 · answered by Anonymous · 3⤊ 0⤋