Lab 13 - Chordata III Flashcards
mastication
chewing to break down food
most mammals have heterodont dentition, meaning…
differently-shaped teeth for different functions
plantigrade
species are those that place the full length of their foot on the ground during each stride
digitigrade
species that walk with most of the length of their digits, but not the soles of their feet in contact with the ground
unguligrade
species that walk on their tiptoes, often on hooves
examples of plantigrade animals
humans and bears
examples of digitigrade animals
dogs and cats
examples of unguligrade animals
deer and horses
Clade Monotremata has what kind of animals? (2)
platypus and echidna
what are the only oviparous mammals?
Clade Monotremata
Clade Metatheria has what kind of animals?
marsupials
what kind of birth does Clade Metatheria have?
viviparous (live birth)
where do babies of Clade Metatheria finish development?
marsupium
Clade Eutheria contains what kind of animals?
placental mammals
what kind of birth do members of Clade Eutheria have?
viviparous with placenta
What common feature of Aves’ bones has made flight possible?
hollowed bones
What traits in Aves is not an adaptation for flight?
number of openings in the skull
What adaptations do members of Aves have for flying? (3)
air sacs, feathers, lack of urinary bladder
What is a characteristic that distinguishes Crocodilia from Lepidosauria?
the number of chambers in the heart
What group is most closely related to Aves?
Archosauria - extinct Dinosauria
what structure of Mammalia is homologous to scales?
hair
what is the function of hair?
provides insulation and helps to maintain body temp
members of Mammalia also have this gland that secretes milk for their young.
mammary glands
what kind of heart do members of Mammalia have?
four chambered heart
What characteristic distinguishes Metheria from Eutheria?
the presence of a yolk-sac placenta (in Metatheria)
What kind of skull is found in Mammalia?
synapsid
