vertebrates pt 3 (tetrapods -> reptilia)

tetrapods are organisms that have how many feet?

4

→ this enabled them to colonize land and take on new forms

what class falls under the characteristic of tetrapods? what animals do you find in this class?

amphibians

→ salamanders, frogs, toads, sicilians

why are frogs restricted to water?

they do external reproduction in water

why are frogs called “amphibians?”

amphibian means “two lives”
the larval stage is aquatic (can be herbivore or carnivore), then the frog goes through metamorphosis and the adult emerges from water into a terrestrial life stage

in the larval stage in frogs, why do they have gills?

gas exchange

in the terrestrial stage, what do frogs use their skin and lungs for?

their lungs and skin are used for gas exchange

do frogs have a tail in their larval stage? do frogs have a tail in their terrestrial stage?

yes

no; they gain legs so they don’t need a tail to swim anymore

why are amphibian populations declining?

habitat loss + pollution + climate change

fungal infections like chytrid (affects the skin of frogs) + invasive species

acid + pesticides + herbicides

what is the number one reason for biodiversity loss?

habitat loss

what evolutionary advantage do frogs have in development?

amniotic egg with specialized membranes to protect the embryo

→ groups that have this include birds, reptiles, and mammals

class reptilia contains what animals? what subphylum do they fall under? what phylum do they fall under?

lizards, snakes, turtles, alligator/crocodiles, tuatara

subphylum vertebrata

phylum chordata

what characteristics have reptiles adopted that have enabled them to colonize land?

1) scales

2) amniotic egg

→ BOTH prevent them from drying out

3) lungs

4) internal fertilization

tuatara is only found where? what class is it from?

islands on the coast of new zealand

→ class reptilia

they differ from lizards because of their skeletal structure

snakes are ________ lizards

legless

alligators and crocodiles are only found in what regions?

warmer regions

→ because they’re too big and living in cold water in the winter would take them too long to warm up !!

→ largely adapted to aquatic habitats