class mammalia jess ackerman maddy smith. phylum name: chordates subphylum: vertebrata class:...
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Class Mammalia
Jess AckermanMaddy Smith
• Phylum name: Chordates • Subphylum: vertebrata• Class: mammalia • Common Name: mammals
General Characteristics• Hair (insulation and protection)• Sweat glands
– Mammary 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 system• Bilateral Symmetry
Various Body SystemsSystem Type Mammals System
Muscular-SkeletalA mammal has an inner skeleton. It has developed muscles and generally have four limbs attached.
Digestion
A 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.
Circulation A mammal has a four chambered heart, blood vessels and blood within their system.
Respiration A mammal has lungs and breathes in oxygen and gives off carbon dioxide.
Reproduction
A 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.
Symmetry A mammal has bilateral symmetry.
Coloration A mammal can be various shades of brown, black, tan, white.
Anatomy: Skeletal System
• Internal skeletal system• Seven cervical vertebrae
(normally)• Four limbs (usually);
limbs adapted for:– climbing – swimming – flying – running/walking
Anatomy: Respiratory System and Gas Exchange
• Take in oxygen, expel carbon dioxide• Lungs:
– Spongy texture– Epithelium (larger surface area)
• Muscular Diaphragm:– Drives breathing– Divides thorax from abdominal cavity
• Air enters through oral and nasal cavities• Flows through larynx, trachea, and bronchi• Air is sucked into or expelled out of lungs
– Moves down pressure gradiant– Aka “bellows lungs”
• Red blood cells serve as oxygen transports• Four chambered heart pumps blood throughout body
Anatomy: Integumentary System• Three layers: epidermis, dermis, hypodermis• Epidermis:
– Ten to thirty cells thick– Provides waterproof layer– Outermost cells constantly lost– Bottommost cells constantly dividing
• Dermis:– Fifteen to forty times thicker than epidermis– Components include bony structures and blood vessels
• Hypodermis:– Made of adipose tissue– Stores lipids– Provides cushioning and insulation
• Hair
Anatomy: Nutrition and Digestion• Keeping high constant body temperature is
energy expensive• Need nutritious and plentiful diet• Different species adapted to dietary
requirements in a variety of ways– Carnivores (including insectivores)– Herbivores (granivores, folivores, fruivores,
nectivores, etc.)• Size of animal is a factor in diet type
– Small: high-energy requirements– Large: can tolerate slower collection process or
slower digestive process• Developed digestive tract
– Mouth, teeth, esophagus, stomach, intestines
Response to Stimuli
• Eyes– Respond to light, movement, etc.
• Ears– Responsible for hearing and balance
• Nervous System– Complex brain (neocortex) – System of nerves throughout the
body
Anatomy: Reproductive System• Most are vivipary (live young)
– Metatheria– Eutheria—placental mammals– Marsupials—undeveloped young kept
in pouch• A few lay eggs
– Holotheria (monotremes)• Mammary glands
– Specialized to produce milk– Newborns’ primary source of nutrition
Classes: 3 subclasses
• Holotheria (monotremes, egg laying mammals)
• Metatheria (marsupials, pouch mammals)• Eutheria (placental mammals)
Holotheria
• Ex: duck billed platypus, spiny ant eaters • Reproduction: females lay eggs, or carry in
pouches• Feeding practices: varied (ant eaters use sticky
tongue, platypus eats freshwater invertebrates, etc.)
Metatheria
• Ex: kangaroos and opossums• Reproduction: young are born in undeveloped
stage, complete development in pouch• Feeding practices: varied
Eutheria
• Ex: humans, lions, etc. • Reproduction: young remain in mothers until
development is complete• Feeding practices: varied