3 General Characteristics Hair (insulation and protection)Sweat glandsMammary glands (produce milk for young)Differentiation of teeth (incisors, canines, premolars, molars)3 middle ear bones (malleus, incus, stapes)Jaw (composed of dentary and squamosal) Endotherms (constant body temperature)Complex nervous systemBilateral Symmetry
4 Various Body Systems System Type Mammals System Muscular-Skeletal A mammal has an inner skeleton. It has developed muscles and generally have four limbs attached.DigestionA mammal has a developed digestive tract with mouth, teeth, stomach, intestines. Herbivores eat plants, carnivores eat meat and omnivores eat both.NervousA mammal has a highly developed brain, nerves and sensory organs such as eyes, nose, mouth, ears and touch.CirculationA mammal has a four chambered heart, blood vessels and blood within their system.RespirationA mammal has lungs and breathes in oxygen and gives off carbon dioxide.ReproductionA mammal reproduces sexually with the female being fertilized by the male internally. Mammals have live birth and care for their young for quite a time after birth.ExcretionA mammal gas kidneys and is covered with skin. The skin has hair. Mammals are warm blooded.SymmetryA mammal has bilateral symmetry.ColorationA mammal can be various shades of brown, black, tan, white.
6 Anatomy: Respiratory System and Gas Exchange Take in oxygen, expel carbon dioxideLungs:Spongy textureEpithelium (larger surface area)Muscular Diaphragm:Drives breathingDivides thorax from abdominal cavityAir enters through oral and nasal cavitiesFlows through larynx, trachea, and bronchiAir is sucked into or expelled out of lungsMoves down pressure gradiantAka “bellows lungs”Red blood cells serve as oxygen transportsFour chambered heart pumps blood throughout body
7 Anatomy: Integumentary System Three layers: epidermis, dermis, hypodermisEpidermis:Ten to thirty cells thickProvides waterproof layerOutermost cells constantly lostBottommost cells constantly dividingDermis:Fifteen to forty times thicker than epidermisComponents include bony structures and blood vesselsHypodermis:Made of adipose tissueStores lipidsProvides cushioning and insulationHair
8 Anatomy: Nutrition and Digestion Keeping high constant body temperature is energy expensiveNeed nutritious and plentiful dietDifferent species adapted to dietary requirements in a variety of waysCarnivores (including insectivores)Herbivores (granivores, folivores, fruivores, nectivores, etc.)Size of animal is a factor in diet typeSmall: high-energy requirementsLarge: can tolerate slower collection process or slower digestive processDeveloped digestive tractMouth, teeth, esophagus, stomach, intestines
9 Response to Stimuli Eyes Ears Nervous System Respond to light, movement, etc.EarsResponsible for hearing and balanceNervous SystemComplex brain (neocortex)System of nerves throughout the body
10 Anatomy: Reproductive System Most are vivipary (live young)MetatheriaEutheria—placental mammalsMarsupials—undeveloped young kept in pouchA few lay eggsHolotheria (monotremes)Mammary glandsSpecialized to produce milkNewborns’ primary source of nutrition