-
amnion
one of the embryonic membranes of reptiles(including birds) and mammals; encloses a fluid-filled cavity that envelops the embryo
-
amniotic egg
the egg of reptiles, including birds; contains a membrane, the amnion, that surrounds the embryo, enclosing it in a watery environment and allowing the egg to be laid on dry land
-
cartilage
a form of connective tissue that forms portions of the skeleton; consists of chondrocytes and their extracellular secretion of collagen
-
craniate
an animal that has a skull
-
mammary gland
a milk-producing gland used by female mammals to nourish their young
-
marsupial
a member of the clade Marsupalia, which includes mammals whose young are born at an extremely immature stage and undergo further development in a pouch, where they remain attached to a mammary gland; like kangaroos, opossums, and koalas
-
monotreme
a member of the clade Monotremata, which includes mammals that can lay eggs; include platypuses and spiny anteaters
-
nerve cord
a major nervous pathway consisting of a cord of nervous tissue extending lengthwise through the body, paired in many vertebrates and unpaired in chordates
-
notochord
a stiff but somewhat flexible, supportive rod that extends along the head-to-tail axis and is found in all members of the phylum Chordata at some stage of development
-
pharyngeal gill slit
one of a series of openings, located just posterior to the mouth, that connects the throat to the outside environment; present (at some stage of life) in all chordates
-
placenta
in mammals, a structure formed by a complex interweaving of the uterine lining and the embryonic membranes, especially the chorion; functions in gas, nutrient, and wastes exchanges between embryonic and maternal circulatory systems, and also secretes the hormones estrogen and progesterone, which are essential to maintaining pregnancy
-
placental
referring to a mammals possessing a complex placenta
-
post-anal tail
a tail that extends beyond the anus, and contains muscle tissue and the most posterior part of the nerve cord; found in all chordates at some stage of development
-
vertebral column
a column of serially arranged skeletal units (the vertebrae) that enclose the nerve cord in vertebrates; the backbone
-
vertebrate
an animal that has a vertebral column
|
|
