Save
Busy. Please wait.
Log in with Clever
or

show password
Forgot Password?

Don't have an account?  Sign up 
Sign up using Clever
or

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
Your email address is only used to allow you to reset your password. See our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
focusNode
Didn't know it?
click below
 
Knew it?
click below
Don't Know
Remaining cards (0)
Know
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

ZOOL 320 - CH 22

Primitive Mammals

QuestionAnswer
reversed triangles in molar teeth holotheria
tribosphenic molars with protocone and talonid tribosphenida
braincase. double rooted cheek teeth. initially quadrate-articular and squamosal-dentary in jaw articulation. early mammals
middle ear evolved independently three times in early mammals
expansion of cerebrum from dorsal ventribular ridge of dorsal pallium bird
expansion of cerebrum from lemnopallium of dorsal pallium mammal
docodont. triconodont. symmetrodont. dryolestid. holotheria. tribosphenida. mesozoic mammals
glenoid cavity oriented horizontally. scapula immobile. both clavicle and interclavicle. primitive shoulder girdle
cusps on their molars are concave anteriorly on the uppers and concave posteriorly on the lowers, indicating retraction of the mandible during chewing. multituberculate
cusps on their molars are concave posteriorly on the uppers and concave anteriorly on the lowers, indicating protraction of the mandible during chewing. rodents
forelimb placed under girdle closer to midline. shoulder girdle moves with forelimb during the stride. excursion of the shoulder girdle in therian mammals
shoulder joint immobile. glenoid laterally oriented. both coracoid and procoracoid. primitive
scapulocoracoid fused Derived (A)
acromion process of scapula strongly overturned. glenoid oriented downward. proximal head of humerus spherical and inturned. procoracoid reduced or lost. theriiformes
interclavicle lost. supaspinous fossa. theria
platypus. long-nosed echidna (New Guinea). short-nosed echidna (Australia). monotremes
modern forms have reduced teeth as juveniles before losing them monotremes
early forms had teeth, not tribosphenic molars monotremes
cochlea structure uncoiled early mammals
cochlea structure half a coil monotreme
cochlea structure coiled up to 360 degrees theria
ampulla, utriculus, sacculus, cochlea, semicircular canals multiple coils of therian mammals
obturator foramen first appears in synapsids
ilium extended farther forward in mammals
bone present in monotremes, marsupials, and earliest placentals marsupial bone
monotreme, lays eggs, suckles young platypus
passages from the uterus, bladder, and intestine open into the cloaca as in reptiles. monotremes
passages form uterus and bladder exit together but the anal exit is separate. marsupials
usually separate openings for the uterus, bladder, and intestine. placental mammals
sidewall of braincase is from alisphenoid therian synapomorphy
lost interclavicle. procoracoid lost with theriiformes. coracoid reduced as process on scapula. supraspinous fossa is new. therian shoulder girdle
have small cervical ribs monotremes
superposition of astragalus over calcaneum in therians
marsupial bones originally thought to support the pouch, but present in monotremes, basal placentals, and even tritylodont cynodonts. epipubic
the bones stiffen the trunk in them during walking when one hindlimb and diagonally opposite forelimb are forward and others back. the opossum
jugal forms portion of jaw glenoid. flared nasal bones. 5 upper incisors and 4 lower. 3 premolars. 4 molars. inflected angle to jaw. marsupial (opossum, Didelphis)
rectangular nasal bones. jugal ends before glenoid. auditory bulla. noninflected angle to jaw. 2 molars. 4 premolars. 3 upper and lower incisors. placental (raccoon, Procyon)
shrew opossum, monitor del monte, tasmanian devil, rabbit-eared bandicot, koala, rat kangaroo, honey possum, marsupial mole, and opossum are examples of marsupials
shearing teeth in carnivorous forms is an adaptation of this marsupial borhyaena
divergent first toe for climbing is an adaptation of this marsupial opossum
syndactylous 2nd and 3rd toes in this marsupial for grooming fur kangaroo
a giant herbivorous marsupial from the Pleistocene of Australia, about 11 feet in length. diprotodon
dog-like carnivore, cat-like carnivore, arboreal glider, fossorial herbivore, and digging ant feeder are examples of this. strongest examples or convergent evolution in biology.
How do tribosphenic molars work? occlusion between teeth of upper and lower jaw.
group of primitive placentals with lower metabolic rates. tongue retractor muscles originate on sternum. xenarthra
lost all incisors and canine. large, recurved claws. caniniform premolar. gets name from extra articular surfaces of vertebrae. xenarthra
have interclavicle and coracoid bones marsupial newborns
front claws act as holdfasts, shoulder arch assist in wriggling crawl of body. marsupial newborns
in mammalian placenta, choriovitelline placenta is associated with the yolk sac
in mammalian placenta, chorioallantoic placenta is in basic placental mammal
used for countercurrent flow for thermoregulatiton vasular plexus
carnivorous marsupials of South America of upper Oligocene to Miocene age, was as large as a wolf. Borhyaena
of Pliocene age, was comparable to a jaguar in size and paralleled in a remarkable way the large sabertooth cats. Thylacosmilus
Created by: dominatrix
Popular Science sets

 

 



Voices

Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!
"Know" box contains:
Time elapsed:
Retries:
restart all cards