<Ul> <Li> Frog: Xenopus (X. laevis and tropicalis). Good embryo supply . Especially suitable for microsurgery . </Li> <Li> Zebrafish: Danio rerio . Good embryo supply . Well developed genetics . </Li> <Li> Chicken: Gallus gallus . Early stages similar to mammal, but microsurgery easier . Low cost . </Li> <Li> Mouse: Mus musculus . A mammal with well developed genetics . </Li> </Ul> <Li> Frog: Xenopus (X. laevis and tropicalis). Good embryo supply . Especially suitable for microsurgery . </Li> <Li> Zebrafish: Danio rerio . Good embryo supply . Well developed genetics . </Li> <Li> Chicken: Gallus gallus . Early stages similar to mammal, but microsurgery easier . Low cost . </Li>

What characteristics are common to all cells at some point in development