Fluffy, insulating feathers that lie next to bird's body
Made of stiff central shaft with many side branches & Cover the body and wings of birds to form a streamlined flying surface
Internal organ in birds that stores food
Upward pressure on the wing that keeps a bird in the air
Internal organ in birds that grinds food
Found in mammals, an organ in mother's body that produces nutritious milk
Large muscle under mammals' lungs to help bring air into them
Mammals that lay eggs
Mammals with pouches
Length of time between fertilization and birth
Meat and plant eater
Mammals that have embryos that develop in mother's uterus until its body systems can function independently
A group of mammals that have opposable thumbs and binocular vision
An endothermic vertebrate that has feathers, a four-chambered heart, and lays eggs
An endothermic vertebrate that has a four-chambered heart, skin covered with fur or hair, and young fed by mother's milk
Found in mammals, an organ in pregnant female mammals that passes materials such as food, oxygen and wastes between the mother and the developing embryo
Air molecules pushing
A mammal having hooves
A mammal with specialized teeth
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