Classes of Phylum Chordata Flashcards
What are the five main classes of Phylum Chordata?
Mammalia, Reptilia, Amphibia, Aves, and Fish
What’s unique about the classification of fish?
It is no longer a normal, distinct class; scientists have broken it into three super-classes. “Fish” is a general category, not a specific class anymore
What are the main characteristics of mammals (Class Mammalia)?
Hair/Fur, endothermic vertebrates, give birth to live offspring (viviparous), provide milk to offspring through mammary glands, possess a diaphragm. four-chambered hearts, skin glands, different types of teeth, and one jawbone.
How many orders are there in Class Mammalia?
About 27
What’s the difference between marsupials and placental mammals?
Placental mammal offspring are born fully mature; marsupials carry their freshly born offspring in pouches until they are ready to function on their own.
Which order of Class Mammalia lays eggs?
Monotremata (duck-billed playpus and two types of spiney anteater)
Which order of Class Mammalia contains the orca whale?
Cetacean
Which order of Class Mammalia contains the manatee?
Sirenia
Which order of Class Mammalia contains rabbits and hares?
Lagomorpha
Which order of Class Mammalia contains rats and mice?
Rodentia
Which order of Class Mammalia contains moles?
Insectivora
Which order of Class Mammalia contains lions and tigers?
Carnivora
Which order of Class Mammalia contains sloths and anteaters?
Edentata
Which order of Class Mammalia contains bats?
Chiroptera
Which order of Class Mammalia contains us?
Primates
What are the main characteristics of Class Reptilia?
Ectothermic vertebrates, have rough, dry, overlapping scales and no skin glands, are oviparous (lay eggs), their eggs have an amniote (leathery protective coating), move in a creeping or burrowing manner, breathe with lungs, have a four section body, and four-chambered hearts
What’s the difference between internal and external fertilization?
Internal fertilization: when the male of the species provides his genetic material to the egg while it’s inside of the female.
external fertilization: when the male provides his genetic material after the female lays the egg
What are the four orders of Class Reptilia?
Squamata, Crocodilia, Rhyncocephalia, and Testudinia
Which order of Class Reptilia contains snakes and lizards?
Squamata
Which order of Class Reptilia contains turtles and tortoises?
Testudinia
Which order of Class Reptilia contains tuataras?
Rhyncocephalia
Why do reptile urinary systems to save as much water within the body as possible?
Because water helps reptiles maintain their body temperature in their environment.
What are the main characteristics of Class Amphibia?
four legs, are oviparous, breathe through their skin and through lungs, go through metamorphosis
What is metamorphosis?
when an organism goes through drastic changes to its primary characteristics when developing into an adult (ex. caterpillar to butterfly and tadpole to frog).
Why do most amphibians live in moist environments?
to provide their skin with the necessary moisture to breathe efficiently
Some amphibians use amplexus fertilization. What is that?
A form of external fertilization where the eggs are fertilized by the male immediately after they come out of the female.
Which came first in evolution: fish, reptiles, or amphibians?
In order: fish, amphibians, reptiles. Fish, particularly lungfish like the coelocanth, developed legs from their lobe fins to become the ancestor of amphibians. Some amphibians adapted for life primarily on land, becoming the ancestor for reptiles
What are the three orders of Class Amphibia?
Anura, Caudata, and Gymnophiona
Which of the orders of Class Amphibia contains the exception to the characteristic of four legs?
Gymnophiona; contains the caecilians, legless amphibians
Which order of Class Amphibia contains salamanders and newts?
Caudata
Which order of Class Amphibia contains frogs and toads?
Anura
What are the main characteristics of fish?
Skin covered in scales. ectothermic, soft shelled eggs that must be laid in water, external fertilization, fully aquatic, limbs modified into fins, gas exchange (respiration) through gills.
Since “fish” isn’t a true class, what are the three super-classes?
Agnatha - jawless fish, Chondricthyes - cartilaginous fish, Osteicthyes - bony fish
What are some fish that Class Agnatha contains?
hagfish and lampreys
What are some fish that Class Chondricthyes contains?
sharks, rays, skates, and ratfishes
What are the two subclasses of fish that Class Osteicthyes contains?
ray-finned fish and lobe-finned fish
Why are sharks in Class Chondricthyes?
Because their skeleton is composed of cartilage, not bone
What’s a swim bladder?
an internal pouch that helps fish regulate their position and buoyancy in the water
What are the main characteristics of Class Aves?
Feathers and wings, lightweight ossified skeleton, endothermic, lungs with air sacs, beak or bill, scales on feet and legs, amniotic egg
How many orders of Class Aves are there?
Around 23
Why is the classification of birds changing?
because of their strong similarities and shared evolutionary roots with reptiles, a large number of scientists are pushing to turn Aves into a subclass of Reptilia.
What are feathers made of?
Keratin
What enables birds to fly?
Hollow bones
