umbilical cord

long connecting mass between the developing embryo or fetus and the placenta: 'Do Klingon newborns cry when their umbilical cords are cut?'

placenta

organ in most mammals — supplies food and oxygen to the foetus and passes back waste during gestation — attached to the wall of the…

exoskeleton

hard outer structure that provides both structure and protection to creatures such as insects and crustaceans (and perhaps exotic alien life). May also refer to…

retina

the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs

sperm(atozoon)

often motile gamete which fertilizes the egg in sexual reproduction

cholesterol

lipid biomolecule synthesized by all animal cells; an essential component of animal cell membranes

anus

the opening of the GI tract where solid waste is expelled

tonsil

one of a set of lymphoid organs facing into the aerodigestive tract, which play an important role in the immune system

lymph

colourless, watery, coagulable bodily fluid which bathes the tissues and is carried by the lymphatic system into the bloodstream; it resembles blood plasma in containing…

dopamine

neurotransmitter that plays several important roles in the brain and body, involved in motor control, hormone release, and perceived desirability or aversiveness of behaviors