Cloacal membrane — Tail end of human embryo from fifteen to eighteen days old. Latin membrana cloacalis Gray s … Wikipedia
Cloaca — For other meanings, see Cloaca (disambiguation). An avian cloaca or vent; in this example, a red tailed hawk (Buteo jamaicensis) … Wikipedia
reproductive system, animal — Introduction any of the organ systems by which animals reproduce. The role of reproduction is to provide for the continued existence of a species; it is the process by which living organisms duplicate themselves. Animals compete with… … Universalium
sex — /seks/, n. 1. either the male or female division of a species, esp. as differentiated with reference to the reproductive functions. 2. the sum of the structural and functional differences by which the male and female are distinguished, or the… … Universalium
Development of the reproductive system — The development of the reproductive system is a part of prenatal development, and concerns the sex organs. It is a part of the stages of sexual differentiation. Because its location to a large extent overlaps the urinary system, the development… … Wikipedia
reptile — reptilelike, adj. reptiloid /rep tl oyd /, adj. /rep til, tuyl/, n. 1. any cold blooded vertebrate of the class Reptilia, comprising the turtles, snakes, lizards, crocodilians, amphisbaenians, tuatara, and various extinct members including the… … Universalium
vertebrate — /verr teuh brit, brayt /, adj. 1. having vertebrae; having a backbone or spinal column. 2. belonging or pertaining to the Vertebrata (or Craniata), a subphylum of chordate animals, comprising those having a brain enclosed in a skull or cranium… … Universalium
endocrine system — Group of ductless glands that secrete hormones necessary for normal growth and development, reproduction, and homeostasis. The major endocrine glands are the hypothalamus, pituitary, thyroid, islets of Langerhans, adrenals, parathyroids, ovaries … Universalium
animal development — Introduction the processes that lead eventually to the formation of a new animal starting from cells derived from one or more parent individuals. Development thus occurs following the process by which a new generation of organisms is produced by … Universalium
Cloaca (embryology) — For other uses, see Cloaca. Cloaca (embryology) Tail end of human embryo thirty two to thirty three days old. Cloaca is visible at center left. The endodermal cloaca is labeled with green, while the ectodermal cloaca is seen as a colorless crest… … Wikipedia