test 3 Flashcards
what are the deuterostomes?
echinoderms
hemichordates
chordates
fish
reptiles
amphibians
mammals
primates
what makes deuterostomes different
anus develops from the blastophore
radius cell cleavage
what are examples of echinoderms
starfish
sand dollars
what does echinoderm mean?
echino - spiny
derm - skin
How does the echinoderm’s body plan shift during development?
larvae - bilateral symmetry
adults - pentaradial symmetry
Echinoderms have this type of skeleton
endoskeleton
what are the two surfaces of echinoderms?
aboral surface - spiny side (madreporite)
oral surface - mouth side (mouth angle plates)
what are ossicles?
calcium-rich plates
how is the endoskeleton formed?
ossicles compiled together with perforated pores with modifiable collagenous tissue surrounding them
what is the water-vascular system?
a hydraulic system that aids in movement and feeding
what is the structure of the water-vascular system?
central ring with a madreporite that pushes water into the radial canals of each segment.
changes in water pressure allow for the ampulla to engage / move tube feet.
what is the meadroporite?
opening for water entry
what is the ampulla
muscular sac for tube feet control
how does the echinoderm coelom aid the starfish?
circulation and respiration through papulae extensions
how do echinoderms reproduce?
small % asexually repro by splitting and reaggregation
most take part in external sexual repro
how come we know so much about the extinct classes of echinoderms?
skeleton allows for fossilization
how do hemichrodates differ from chordates?
hemi - pharyngeal gill slot & hollow dorsal nerver cord
chordates - notocord, postanal tail, pharyngeal gill slot & hollow dorsal nerver cord
what are the three divisions of chordate phylum?
urochordata
Cephalochordata
vertebrata
what are the two invertebrates subphylum?
urochordata
cephalocordata
what are the 4 distinct evolutions of chordates?
nerve cord
notocord
pharyngeal slits
postanal tail
what does the nerve cord turn into?
brain and spinal cord
what does the notocord turn into?
spinal column in vertebrates
what does the pharyngeal slit do? what did it evolve into?
connects the pharynx with outside
used to be gill slits
what are examples of the urochordates?
tunicates
what are the characteristics of subphylum urochordata?
marine
sessile - attach to substrate and develop into filter-feeders
obtain food by ciliary action
larvae exhibit basic characteristics of chordates but do not maintain through lifecycle
what is an example of a cephalochordate?
lancelet
characteristics of the cephalocordates?
marine
not sessile but spend most time burrowed in sand
filter feeding
notocord and nerve cord present throughout life
what are examples of the subphylum vertebrata
hagfishes
lampreys
jawed vertebrates
who are the vertebrates?
fishes
amphibians
reptiles
birds
mammals
what is the neural crest? what are the embryonic cells?
a unique group of embryonic cells that forms many vertebrate structures / helps lay pattern for vertebral column.
blastula / glastula cells
what are the three characteristics of vertebrates?
neural crest
internal organs
endoskeleton
what is the endoskeleton made of? why is it important?
cartilage or bone
allows for large body growth and movement
saves energy by not having to molt
characteristics of fish
vertebral column
jaws and paired appendages
internal gills
single-loop blood circulation
nutritional deficiencies
fusiform body shape
why do gills close when a fish is out of water?
oxygen cannot be taken from the air, gills close, mucous is secreted over the gills to prevent drying out.
what is an agnatha
jawless fish
what do hagfish eat? what do lampreys eat?
hagfish - dead things
lampreys - live things
what did jaws develop from?
anterior gill arches made of cartilage
what are the two classes of agnatha? what does agnatha mean?
jawless vertebrates
hagfishes and lampreys
what is the hagfish’s defense mechanism?
excretion of slime that keeps the skin wet
what are the characteristics of lampreys?
no jaws, circular rows of teeth
dorsal and caudal fins - more movement
predatory - attach to live prey and feed on tissue
what is the evolutionary benefit of jaws?
allows organisms to predate larger organisms thanks to being able to bite
jaws/masseter muscles allow for organism to return to fusiform shape for increased hydrodynamic movement
what are the examples of chondrichthyes?
sharks, rays, skates
what are the characteristics of chondrichthyes?
jawed fish
paired fins
paired nostrils
scales
two-chambered heart
skeleton made from cartilage
do sharks have a real brain? why or why not?
yes, there are regions of the brian designed for special functions
what is a shark’s liver filled with and why?
oil
maintains buoyancy
to move up or down the water column a shark must keep moving and angle their fins up or down like a gliding airplane.
what is a spiral valve? why is it important?
a part of the digestive tract that mixes chyme
moving chyme through a spiral keeps it there for longer allowing and increases surface area in the tract
why are teeth in sharks important/how do they form?
first vertebrates to develop them
evolve from rough scales on the skin of the mouth
what is the lateral line system? why is it important?
a series of sensory organs under the skin that detects changes in pressure waves
a membrane covers the organisms’ eyes to protect them since the lateral line system acts like eyes taking in and processing sensory information.
what is oviparous reproduction? which condrichthyes are oviparous?
internal fertilization then laying egg cases
skates
what is ovoviviparous reproduction? which condrichthyes do this?
internal fertilization and retained within the mother til birth
often times the first hatched egg will eat the other embryos
sharks - great white, mako, nurse, and tiger
what is viviparous reproduction? which condrichthyes do this?
internal fertilization that is attached to a placenta
sharks
how is the bony fish evolution different than the chondrichtyes?
heavy internal skeleton made of bone instead of a light, cartilaginous one
what is the swim bladder? why is it important? how does it help fish like gold/beta fish?
membranous, gas-filled sac that allows fish to regulate buoyant density.
allows fish to move up and down the water column without having to move
certain types of fish can live in areas with less oxygen content because they can move up to surface of water in order to breathe
what controls gas additions to the swim bladder? what controls gas release?
gas gland
oval body
what is the gill cover? why is the gill cover important?
an operculum, hard plate, that covers gills and flexes allowing water to be pumped over gills
what are the characteristics of a counter-current exchange system?
blood flow run parallel with water
diffusion gradient moves in a positive direction across blood vessels to absorb most amount of O2
PO2 in water is always greater than the PO2 in blood
what is the difference between ray and lobe-finned fish?
ray = parallel bony rays stiffen fin, but no muscles in fins
lobe = central co-jointed bones that have fleshy, muscular lobe
what is special about lungfish?
lobe-finned fish that can breathe off of the surface
what did amphibians evolve from?
lobe-finned fish
muscles in fish support animals out of water
what is the importance of the tiktaalik?
transitional species
shoulder / limb bones as well as fins
capable of moving on land but spent most time in water
characteristics of amphibians
legs/limbs for body support and movement
lungs for respiration
increased heart complexity to fuel muscles
rely on water for reproduction
system that prevents desiccation
how do frogs and toads differ?
frogs need to be near water to prevent drying out
toads have a cuticle that keeps them from drying out, can be far from water
characteristics of amphibian skin
no protective layers
permeable
glandular
Classes of amphibians
anura
caudata
apoda
Examples and Characteristics of Anura
frogs and toads
frogs have moist skin & live near water
toads have dry skin and can line in dry environments
eggs are fertilized externally
use metamorphosis
r-selection
Examples and Characteristics of Caudata
salamanders
long body, tails, smooth/moist skin
internal fertilization and laid externally in moist areas
larvae are similar in appearance to the adults
k-selection
why are newts important? what is their defense mechanism?
transitional species between salamanders and frogs
secretion of neurotoxin that blocks the sodium/potassium pumps in the muscle
Examples and Characteristics of Apoda
caecilians
burrowing amphibians
legless
jaws with teeth
internal fertilization
what does the development of scales do?
allows organism to move away from water by being able to retain the water within
what are amniotes? what animal groups are amniotes? what two groups does the amniotic egg link?
organisms that have an amniotic egg
reptiles birds and mammals
birds and reptiles
what are the 4 membranes of the amniotic egg? what do they do?
chorion - allows oxygen entry
amnion - fluid-filled cavity that provides shock absorption
yolk sac - provides nutrients to the embryo
allantois - o2 absorption, co2 excretion, nitrogenous waste excretion
what are the characteristics of reptiles?
amniotic eggs - water tight eggs that are laid out of water
dry skin - prevents water loss
thoracic breathing - increases lung capacity (positive pressure)
ovoviviparous reproduction
3-chambered heart separating oxygenated and deoxygenated blood
what does it mean to be ectothermic?
obtaining heat from external sources, dependent upon ambient temperature
more active when it’s warm, less when it is cold
what are the four surviving orders of reptiles?
chelonia - turtles / tortoises
rhynchocephalia - tuataras
squamata - lizards / snakes
crocodylia - crocodiles / alligators
what was the evolutionary advantage for snakes to lose their legs?
allowed the organisms to be able to burrow
- lead to evolution of chemo/thermoreceptors
how do snake’s teeth differ from most organisms?
teeth face backward therefore food can go in but can’t go back out
what is important about tuataras?
only one extant species
photoreceptor on head that controls circadian rhythm
some characteristics of fish and amphibians
2x the genome o f humans
what is the difference between alligators and crocodiles?
alligator - short, blunt nose
croc - longer, sharp nose
where are crocs, alligators, caimans, and gharials?
croc - tropical / subtropical regians
alligators - Southern US / China
Caiman - central america
gharial - India and burma
what are 2 of the separating characteristics of Crocodylia?
4 chambered heart
diaphragm that separates pulmonary and abdominal cavity
birds and mammals are _____therms?
endotherm
able to generate their own heat
what class are birds a part of?
aves
how/what did the aves class evovle from?
early division of reptiles and dinosaurs, specifically pterosaurs
what are feathers?
modified scales that insulate the organism
why is archaeopteryx important?
link between reptiles and birds
about the size of a chicken
glid down from trees and attack prey
what two traits distinguish birds from reptiles?
feathers
flight skeleton - hollow bones that allow organism to be able to oppose gravity and fly
what is the keelbone?
breastbone that acts as a sternum for chest muscles to attach to
what about the feather’s structure is important?
barbs protrude from shafts and attach with others
maintains rigidity / keeps air from moving through
what type of respiration do birds have?
counter-current respiration
how do circulation and endothermy in birds help them?
efficient oxygenated blood circulation allows for muscles to receive greater amounts of oxygen
a lot of metabolic energy is needed to be abe to fly. therefore, higher body temperatures allow for metabolic reactions to occur at a faster rate.
how do mammals differ from other vertebrates?
hair
mammary glands
diaphragm assisted respiration
placenta
highly developed parental care
specialized teeth
what is hair made of / used for?
keratin-rich filaments that extend from follicles
insulation, camouflage and sensory reception
how do hooves, horns, and antlers compare
hooves - specialized keratin pads
horns - bone surrounded by keratin
antlers - bone not keratin
what arethe only flying mammals
bats
what are the two subclasses of mammals?
prototheria
Theria
what are the characteristicsof prototheria
lay shelled eggs
only one living group - monotremes
what are the characteristics of theria?
viviparous
two living groups - marsupials / placental mammals
what is a cloaca?
a single opening that leads to the digestive and reproductive tract
what are the three types of monotremes
platypus
short nose echidna
long nose echidna
why does the placenta give Eutheria an advantage?
organism can retain fetus for longer which allows the fetus to be born more developed
separates the mother’s / baby’s circulatory systems so that the immune system does not attack the offspring
what adaptation arose from primates living in arboreal environments?
fingers and toes
allowed organisms to move away from predators by going into trees
what is the advantage of binocular vision?
increased depth perception, ability to coordinate movement through arboreal environment
what did primates split into? what are some examples of their species?
prosimians - lemurs, tarsiers
anthropoids - monkeys, apes, humans
what does diurnal mean?
primarily daytime animals that rest at night
due to the ability to see color, more advantageous to be awake and use energy during the day.
what are the characteristics of old-world monkeys?
old world - no prehensile tails, ground-dwelling, nostrils facing down, opposable thumbs
what are the characteristics of hominids? examples?
larger brains than monkeys and lack tails
apes / humans
what are examples of apes?
gibbons, orangutans, gorillas and chimpanzee
what is the difference between bonobos and chimpanzees?
chimpanzees are hostile and very territorial
bonobo - docile
how do hominids and apes method of walking differ?
apes - knuckle-walking, long arms & short legs, distribution of weight across 4 points
hominids - bipedal, distribution of weight across 2 points
what advantages does being bipedal offer?
taller, better able to see over tall grasslands
able to run, more efficient movement
can carry objects / make and use tools
what is the rift valley?
fault line in Africa where the tectonic plates are moving away from each other where it is thought that a cradle of hominid species lived
who is autralopithecus?
“early man” one of the first hominid subspecies
believed that this organism came to be from the drying of the rainforest that used to be the African savannah
adapted to become bipedal once away from arboral env.
who is autralopithecus?
“early man” one of the first hominid subspecies
believed that this organism came to be from the drying of the rainforest that used to be the African savannah
adapted to become bipedal once away from arboreal env.
who is lucy?
the name of the most complete Australopithecus skeleton formed by fossils found in Ethiopia.
who are cro magnon?
first type of homo sapiens
believed that neanderthals and cro magnon interbred
who is lewis leakey?
discovered homo habillis in the rift valley
