sperm+of+fishes
21Megalodon — For other uses, see Megalodon (disambiguation). Megalodon Temporal range: Late Oligocene Early Pleistocene 28–1.5 Ma …
22hormone — hormonal, hormonic /hawr mon ik, moh nik/, adj. /hawr mohn/, n. 1. Biochem. any of various internally secreted compounds, as insulin or thyroxine, formed in endocrine glands, that affect the functions of specifically receptive organs or tissues… …
23Social behaviour in animals — Introduction actions of animals living in communities. Such behaviour may include the feeding of the young, the building of shelters, or the guarding of territory. General characteristics Social behaviour (Social behaviour in animals) …
24evolution — evolutional, adj. evolutionally, adv. /ev euh looh sheuhn/ or, esp. Brit., /ee veuh /, n. 1. any process of formation or growth; development: the evolution of a language; the evolution of the airplane. 2. a product of such development; something… …
25cetacean — cetaceous, adj. /si tay sheuhn/, adj. 1. belonging to the Cetacea, an order of aquatic, chiefly marine mammals, including the whales and dolphins. n. 2. a cetacean mammal. [1830 40; < NL Cetace(a) name of the order (see CET , ACEA) + AN] * * *… …
26annelid — /an l id/, n. 1. any segmented worm of the phylum Annelida, including the earthworms, leeches, and various marine forms. adj. 2. belonging or pertaining to the Annelida. Also, annelidan /euh nel i dn/. [1825 35; see ANNELIDA] * * * Any member of… …
27cephalopod — /sef euh leuh pod /, n. 1. any mollusk of the class Cephalopoda, having tentacles attached to the head, including the cuttlefish, squid, and octopus. adj. 2. Also, cephalopodic, cephalopodous /sef euh lop euh deuhs/. belonging or pertaining to… …
28Vas deferens — Male Anatomy Vertical section of the testis, to show the …
29Panda corydoras — Corydoras panda Scientific classification Kingdom: Animalia …
30biology — /buy ol euh jee/, n. 1. the science of life or living matter in all its forms and phenomena, esp. with reference to origin, growth, reproduction, structure, and behavior. 2. the living organisms of a region: the biology of Pennsylvania. 3. the… …
