Final Exam - Body Parts Flashcards
Gill
organ for respiration in water
Lung
organ for respiration in air
Notochord
stiff rod running longitudinally down the dorsal length of an embryonic vertebrate
backbone
chain of disk-like vertebrae running down the dorsal length of an adult vertebrate
nares
nasal openings
orbits
eye sockets
Purpose and location of temporal fenestrae:
serves to increase the area of attachment of powerful jaw muscles; side of skull
Four types of temporal fenestrae in reptiles:
Anapsid, euryapsid, synapsid, diapsid
Anapsid:
No temporal fenestrae
Euryapsid:
One temporal fenestra located above the postorbital & squamosal bones
Synapsid:
One temporal fenestra located below the postorbital & squamosal bones
Diapsid:
Two temporal fenestrae, one located above & the other located below the contact between the postorbital & squamosal bones
What has anapsid?
primitive reptiles & turtles
What has euryapsid?
ichthyosaurs & plesiosaurs
What has synapsid?
mammal-like reptiles
What has diapsid?
lizards, snakes, crocodiles, pterosaurs, dinosaurs, & birds
Five main anatomical characteristics of Saurischians (Theropods & Sauropods):
- lizard-like hip structure with pubis bone protruding forward.
- teeth in front part of jaw & along sides of jaw (no predentary bone)
- scissors-type jaw (shearing action)
- includes carnivores (theropods) & omnivores (sauropods)
- includes the largest dinosaurs (sauropods)
What are carnivorous dinosaurs called?
theropods
What are omnivorous dinosaurs called?
sauropods
What has a lizard-like hip structure?
saurischians
What has a pubis bone protruding forward?
Saurischians
What has their teeth in front part of jaw and along sides of jaw (no predentary bone)?
Saurischians
What are the largest dinosaurs?
Sauropods
What two groups are included in the Saurischians?
theropods & Sauropods
Five main anatomical characteristics of Ornithischians:
- bird-like hip strucutre with pubis bone protruding forward and backward
- predentary bone in front part of jaw; teeth only along sides of jaw (no teeth in front)
- nutcracker-type jaw (chomping action)
- includes only herbivores
- includes the greatest diversity of dinosaurs
What groups are included in the Ornithischians?
Ornithopods, Stegosaurs, Ankylosaurs, Pachycehpalosaurs & Ceratposians
What has a bird-like hip structure with pubis bone protruding forward and backward?
Ornithischians
What has a predentary bone in front part of jaw; teeth only along sides of jaw (no teeth in front)?
Ornithischians
What has a nutcracker-type jaw?
Ornithischians
What group includes the herbivores?
Ornithischians
What group includes the greatest diversity of dinosaurs?
Ornithischians
Label the ischium, ilium, and pubis on both the Saurischian and Ornithischian pelvis.
See 23a
Locate the jaw articulation point on both the Saurischian and Ornithischian skulls:
See 23a
Endothermic:
Body temperature controlled internally by metabolic processes “warm-blooded”
Ectothermic:
body temperature controlled externally by the ambient environment “cold-blooded”
Homeotherm:
An animal that maintains a constant body temperature (generally endothermic, but some large ectothermic animals in stable climates)
Poikilotherm:
An animal whose body temperature fluctuates significantly (generally ectothermic)
Give six pieces of evidence in support of endothermy in some dinosaurs:
- Stable oxygen isotopes in bones
- Bone microstructure (growth rings, canals, etc.)
- Very low predator:prey biomass ratios in some occurrences
- Broad geographic (latitudinal) distribution
- Dinosaur anatomy is similar to that of early birds, and modern birds are endothermic
- Herding behavior and post-natal care are typical of modern endotherms
Give five pieces of evidence against endothermy in some dinosaurs:
- Fossils of dinosaur skin indicate no fur or feathers for insulation
- Internal skull casts suggest that brain morphology was similar to that of modern reptiles
- Predator:prey biomass ratios are equivocal
- Large amount of food would be required for large endothermic dinosaurs
- Dinosaur anatomy is basically reptilian, and modern reptiles are ectothermic
Label the nares, orbit, and temporal fenestra on the mammalian skulls
See 24a
Reproduction in the Eutherian (“Placental”) mammals:
The embryo develops into a fetus inside a uterus (which is connected by an umbilical cord to a placenta in the uterine wall)
The young are born in a relatively advanced fetal stage (unlike monotremes and marsupials)
this group appeared in the cretaceous and is by far the most abundant and diverse groups of mammals today
When did the Eutherian mammals first appear?
Cretaceous
What is the most abundant and diverse group of mammals?
Eutherians
Embryo:
Earliest ontogenetic (developmental) stage of a mammal, which develops immediately from the fertilized egg; during part of this stage, the embryo possesses a notochord
Fetus:
Next ontogenetic stage of a mammal, which begins when the notochord disappears and the bones of the skeleton begin to be calcified and hardened.
Infant:
The ontogenetic stage that begins at the moment of birth and leads into adolescence, adulthood, etc.
Uterus:
The main reproductive organ in a female mammal, which contains the chorionic sac, which in turn contains the amniotic sac, which in turn houses the developing embryo/fetus.
Umbilical cord:
Tube which connects to developing fetus to the placenta
Placenta:
outgrowth of the wall of the uterus
What five important functions does the placenta serve for the fetus?
- protection
- nutrition
- respiration
- excretion
- hormone secretion
Gestation Period:
Length of time elapses from fertilization of the egg (through the embryonic and fetal stages) to the birth of the infant mammal
Mammaries:
milk glands (contained inside breasts with nipples)
Viviparous:
live-bearing (the placentals & marsupials)
Oviparous:
Egg-laying (the monotremes)
What are the four basic tooth types in mammals?
Incisors, Canines, Premolars, Molars
Incisors:
Flat, chisel-like front teeth for nipping and biting food
Canines:
Sharply pointed corner teeth for stabbing and tearing food
Premolars:
Blade-like side teeth for ripping and tearing food
Molars:
Massive side teeth for chewing and grinding food
tusks of elephants are examples of:
incisors
tusks of walruses are examples of:
canines
fangs of wolves are examples of:
canines
sabers of extinct saber tooth cats are examples of:
canines
cuspids in humans are examples of:
canines
carnassials of carnivores are examples of:
premolars
bicuspids in humans are examples of:
premolars
In what are molars best developed?
ungulates
Dental Formula (in mammals):
Incisors-canines-premolars-molars (2-1-2-3 (in humans))
12 Anatomical characteristics of Homo (compared with the great apes & our hominid ancestors):
- Upright posture & bipedal gait
- “Foramen magnum” (sit of articulation of skull with backbone) positioned on bottom of skull
- Flat-faced skull with short, shallow jaw
- Absence of a “supraorbital ridge” (bony ridge across eyebrow)
- Absence of a “sagittal crest” (narrow ridge on top of skull)
- Rounder (parabola-shaped) “dental arcade” in the jaw
- Incisors proportionately larger, and canines & molars smaller
- Arms shorter than legs
- Small thumbs positioned close to the other four fingers
- Absence of an opposable big toe
- Body sparesely covered with short hair
- Very large brain (largest “crainal capacity” of all primates)
Foramen magnum:
sit of articulation of skull with backbone
supraorbital ridge:
bony ridge across eyebrow
sagittal crest:
narrow ridge on top of skull
What has the largest “cranial capacity” of all primates?
Homo
ilium:
uppermost and largest part of hip bone
ischium:
the curved bone forming the base of each half of the pelvis