BJU Biology Chapter 18: The Endothermic Vertebrates

Class Aves

birds

feathers

distinguishing feature of birds

down feathers

a soft feather that covers the body of young birds and provides insulation to adult birds

contour feathers

large feathers that give shape to a bird's body and help with flying

crop

enlargement of the bird's esophagus that stores food

gizzard

grinds food

air sacs

structures that allow birds to take all of the oxygen out of each inhalation

syrinx

the bird's voice box

number of chambers in a bird's heart

4

courtship

birds' mating rituals

albumen

egg white

incubation

period when birds warm their eggs by sitting on them

altricial

offspring that are completely dependent on parental care

precocial

offspring that can walk, run, swim, and feed themselves at hatching

ways birds navigate during migration

stars, magnetic field of the earth, landmarks

incisors

thin, flat teeth used for biting

canines

pointed teeth used for tearing

molars

flat teeth used for grinding and chewing

ruminents

have a rumen and chew the cud

rumen

stomach chamber in cows and related animals in which symbiotic bacteria digest cellulose

cecum

a pouch connected to the junction of the small and large intestines in which cellulose can ferment

diaphragm

large, flat muscle at the bottom of the chest cavity that helps with breathing

larynx

voice box

number of chambers in a mammal heart

4

placenta

a structure that allows an embryo to be nourished with the mother's blood supply

marsupial

a pouched mammal

mammary glands

specialized organs in mammals that produce milk to nourish the young

monotreme

egg-laying mammal

uterus

a hollow muscular organ in the pelvic cavity of the female, in which the embryo is nourished and develops before birth

estrus

time periods when females are receptive to mating

umbilical cord

a tube containing the blood vessels connecting the fetus and placenta

gestation

pregnancy

rodents

largest group of mammals; gnawing animals

primates

an animal order including lemurs and tarsiers and monkeys and apes

opposable thumb

thumb that enables grasping objects and using tools

bipedal

can walk on 2 legs

prehensile tail

a tail that acts as a kind of a hand for support in trees