| A | B |
|---|
| what are the most important adaptations made by reptiles to be able to live completely w/out water? | waterproof skin- reduces water loss through skin and eggs w/ a protective shell - keeps them from drying out, freeing need to repr. in water |
| Carboniferous period | "age of Amphibians," many insexts and arachnids, swamps and forests covered land |
| first reptiles | stem reptiles - very similar to amphibians |
| Age of the Reptiles | lasted approx. 200 million year. reptiles were dominant land vertebrate |
| therapsids | small mammal-like animals that walked on four legs. could run faster than most mammals, had strong jaws and specialized teeth |
| thecodonts | reptiles that stood up on two long, powerful hind legs. forelegs small w/ claws, long muscular tail to balance body |
| what are though to be descendants of the thecodonts? | dinasaurs, crocodiles, birds |
| dinosaur | "terrible lizard". first were no larger than chickens |
| apatosaurus | herbivore, one of largest dinosaurs. 24 m long and may have weigh as much as 50,000 kg |
| Tyrannosaurrus rex | fierce carnivore that stood 6 m tall |
| The K-T boundary | the period between the end of the Cretaceous period and the beginning of the Tertiary, lasted 5-10 million years |
| extinction of dinosaurs | happened gradually in K-T boundary. climatic changes hurt herbavoires, which in turn hurt carnivores. more abrupt may have been w/ a catastrophic event as well |
| what were the only reptilian survivors after the mass extinction? | turtles, crocodiles, ancestors of other modern reptiles |
| Squamata | snakes and lizards |
| Chelonia | turtles and tortoises |
| Crocodilia | crocodiles |
| Rhynchocephalia | the tuatara - found only on the islands off the coast of New Zealand |
| Snakes evolved from ______ | burrowing lizards |
| What three groups can Chelonians be divided into? | tortoises, sea turtles, freshwater turtles |
| Tortoises | live entirely on land |
| Sea turtles | live in oceans |
| Freshwater turtles | sun selves on land, feed in water. have webbed feet |
| plastron | the flat shell that covers the bottom of the turtle |
| what does a shell consist of? | a series of bony plates covered with hornlike scales |
| diffs between crocodiles and alligators | croc has narrower jaw,more pointed face |
| Crocodilians, diff kinds | alligators, crocodiles, caimans, gavials |
| diff between amp. and rept. legs | rept legs tucked closer to body, have claws |
| keratin | an insoluble protein (in water) formed from hard, dry scales voering the skin |
| feeding | generally carnivorus - insects when young, then other animas. some are herbivores, eat leaves and fallen fruit |
| feeding adaptions | flexible jaws for snakes, sharp teeth for all except turtles who have sharp birdlike beaks, poisonous snakes have venomous fangs, gila monster adn mexican beaded lizard only poisonous lizards, hold onto prey as venom flows from teeth to wound |
| do most reptiles chew their food? | no, most swallow in pieces small enough, snakes whole |
| ectotherm | an animal whose body temp. is determined by the environment |
| endotherm | an animal that uses food energy to maintain a constant body temperature |
| are reptiles ectotherms or endotherms | ectotherms |
| circulation in reptiles | partially divided 3 chambered heart (all except crocodilians) |
| main goal of excretory system in reptiles | to retain water |
| parietal eye | a third eye on the top of the head of tuataras and a few lizards. can't be seen externally. can sense light |
| advantages of internal fertilization | makes water unnecessary, fragile sperm are protected from environment |
| how many eggs to reptiles lay at a time, generally | bt/w 8 and 100 |
| yolk | the food source for the developing embryo |
| amnion | a fluid-filled envolope that cushions the embryo |
| allantois | a membrane sac in the egg that stores wastes and is the site for gas exchange |
| chorion | provides another layer of protection in the egg and also helps regulate gas exchange |
| albumin | egg white, contained in eggs of tutles and crocodilians |
| do all reptiles lay eggs? | no, some snakes and lizards give birth to live animals |
| do most reptiles care for their young? | no, most do not |
| what reptile is known for caring for its yound? | the american alligator |
