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an extinct group of reptiles from which mammals evolved

mammary glands

glands that make a nutritious fluid for embryos called milk


teeth used to cut food


teeth used to stab and slice teeth


teeth used to grind up food

milk teeth

a young mammal's first small teeth


a large muscle in mammals that helps bring air into the lungs


mammals that lay eggs


mammals with pouches in which the young go in for protection

placental mammals

Mammals that have embryos that develop in mother's uterus until its body systems can function independently

gestation period

time in which embryo develops within the mother

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