1 air sac - one of several sacs attached to a bird's lungs into which air moves when a bird inhales; allows for the one-way flow of air through the respiratory system.
2 amniotic egg - egg composed of shell and membranes that create a protected environment in which the embryo can develop out of the water.
3 carapace - in crustaceans, the part of the exoskeleton that covers the cephalothorax; in turtles and tortoises, the dorsal part of the the shell.
4 crop - in earthworms, part of the digestive system in which food can be stored; in birds, structure at the lower end of the esophagus in which food is stored and moistened.
5 ectotherm - animal that relies on interactions with the environment to help it control body temperature.
6 endoderm - animal that generates its own body heat and controls its body temperature from within.
7 feather - structure made mostly of protein that develops from a pit in a bird's skin.
8 gizzard -in earthworms, part of the digestive system in which food is ground into smaller pieces; in birds, a muscular organ that helps in the mechanical breakdown of food.
9 plastron - ventral part of a turtle's or tortoise's shell.
2 amniotic egg - egg composed of shell and membranes that create a protected environment in which the embryo can develop out of the water.
3 carapace - in crustaceans, the part of the exoskeleton that covers the cephalothorax; in turtles and tortoises, the dorsal part of the the shell.
4 crop - in earthworms, part of the digestive system in which food can be stored; in birds, structure at the lower end of the esophagus in which food is stored and moistened.
5 ectotherm - animal that relies on interactions with the environment to help it control body temperature.
6 endoderm - animal that generates its own body heat and controls its body temperature from within.
7 feather - structure made mostly of protein that develops from a pit in a bird's skin.
8 gizzard -in earthworms, part of the digestive system in which food is ground into smaller pieces; in birds, a muscular organ that helps in the mechanical breakdown of food.
9 plastron - ventral part of a turtle's or tortoise's shell.