Animals
mammary
characteristics unique to mammals include ______ glands in females that produce milk to nourish young
notochords
chordates- jawless fish: lampreys & hagfishes both lack vertebrae and have ______ as adults
cartilage
chordates- jawless fish: they have no true jaws or teeth, & their skeletons were made of ________
ectothermic
reptiles rely on the environment to maintain their body temperature (______)
drier
reptiles were the first vertebrates to evolve adaptations to ____ conditions
internal
the bones of vertebrates form an _____ skeleton
coeloms
flatworms do not have _____
pharyngeal
____ pouches are paired structures in the throat region, which is also called the pharynx
sponges
_____ are the most ancient members of the kingdom Animalia, their Phylum is Porifera
jaws
_____ make it possible to bite & chew plants & other animals
marsupials
______ bear live young that usually complete their development in an external skeleton
invertebrates
______ include all animals that lack a backbone, or vertebral column
dorsal
a ___ is a hollow nerve cord in chordates
tissue
a ____ is a group of cells that perform a similar function
notochord
a ____ is a long supporting rod that runs through the body just below the nerve chord
chordates
all _____ exhibit four characteristics during at least one stage of life
oxygen
all animals must breathe to obtain _____
water
amphibians are vertebrates that also, with some exceptions, require ____ for reproduction
heterotrophs
animals are ____- they obtain nutrients & energy by eating other organisms
cephalization
animals with bilateral symmetry typically exhibit _____, the concentration of sense organs & nerve cells at their anterior end
ammonia
animals' metabolic processes generate CO2 & other waste products, some of which contain nitrogen in the form of ______
bony
another group of ancient fishes evolved skeletons made of true bone, the _____ fishes
multicellular
besides being heterotrophs, animals are also ______
endothermic
birds are reptiles that regulate their internal body temperature (______)
Aves
birds, the traditional class _____, make up a clade that is part of the clade containing dinosaurs
receptors
gathering & responding to information- the nervous system gathers info using cells called _______
homeostasis
in animals, maintaining _____ is the most important function of all body systems
external
insects & some other invertebrates have _____ skeletons
ray-finned
most living bony fishes belong to a huge group called the ____-____ fishes
musculoskeletal
muscles work together with some kind of supporting structure called a skeleton to make up the ____ system
feedback
often, homeostasis is maintained by ______ inhibition or negative feedback, a system in which the product or result of a process limits the process itself
egg laying
only 5 species of the ____ ____ monotremes exist today
skeletons
ray-finned fishes are aquatic vertebrates with _____ of true bones; most have paired fins, scales, & gills
appendages
segmented, bilateral symmetrical animals typically have external ______ on both sides of their body
radial
some animals exhibit ____ symmetry, in which body parts extend from a central point
bilateral
the most successful animal groups exhibit _____ symmetry, in which a single imaginary plane divides the body into left & right sides that are mirror images of one another
Annelids
their Phylum is Annelida- include earthworms, marine worms, & leeches, they are worms with segmented bodies & true coeloms
arthropods
their Phylum is Arthropoda
Cnidarians
their Phylum is Cindaria- includes jellyfishes, sea fans, hydras, & coral. They are aquatic carnivorous animals
mollusks
their Phylum is Mollusca- includes snails, slugs, clams, and squid, they have free swimming larva, or immature stage, called a trochophore
nematodes
their Phylum is Nematoda, they are unsegmented worms
flatworms
their Phylum is Platyhelminthes, they are soft, unsegmented, flattened worms that have tissues & internal organs
Echinoderms
their phylum is Echniodermata, they have spiny skin & an internal skeleton, they also have a water vascular system
cell walls
unlike plants, animal cells lack _____ _____