Post on 16-Dec-2015
MammalsHave hairAbility to nourish their young with milkBreathe air4-chambered heartEndotherms
EnvironmentLive in a wide variety of ecosystems Land, water, and flying mammals
Food SourceMust eat 10 times as much food as a reptile to
maintain body heatUse jaws and teeth to eat (Specialized teeth)Digestive tract absorbs nutrients for the body to use
Maintaining Homeostasis - Internal(Circulation, Respiration, Excretion)
lungs to breatheHave a diaphragm- powerful muscle2 separate loops in circulatory system and a 4-
chamber heartKidneys help maintain homeostasis by filtering urea
from the blood as well as by excreting excess water or retaining needed water
Maintaining Homeostasis - External(Response)
Highest developed brainCerebral cortex- center of thinking and other
complex behaviorsHighly developed senses to detect and respond to
stimuli from their external environment
MovementBackbone that flexes both vertically and side to
side.Very flexibleMove in a variety of ways depending on their
lifestyleReproductionInternal fertilizationFeed on mother’s milkMost care for their youngDuration of care varies among species
Evolutionary MilestoneEndotherm, Hair, mammary glands, breathe air, 3
middle-ear bones
Picture and Vocabulary
Picture on page 827, Fig 32-7 – homologous structures
Vocabulary: mammary gland (821), cerebral cortex (825)