Unit 8- Chapters 23 and 24 Flashcards
Vocabulary and Key Ideas
Animals are the most…
…physically diverse kigndom of organisms
all animals share…
…a set of characteristics
collagen
a three-stranded protein unique to animal
homeotic
genes that are a class of genes that control early development
homeobox
defini the head-to-tail pattern of development in animal embryos
Each animal phylum has…
…a unique body plan
animals are grouped using…
…a variety of criteria
A comparison of structure and genetics reveals…
… the evolutionary history of animals
vertebrate
an animal with an internal segmented backbone
invertebrate
an animal without internal segmented backbones
phylum
a group of animals defined by structural and functional characteristics that are different from every other animal group
bilateral symmetry
symmetry that divides an animal equally along only one plane
radial symmetry
symmetry that divides an animal in a circle around a central axis
protostome
when the mouth is formed first
deuterostomes
when the anus is formed first
sponges have… but no…
…specialized cells …tissues
Cnidarians are the…
…oldest existing animals that have specialized tissues
sessile
unable to move
filter feeders
eat by straining particles from the water
polyp
cylindrical tubes with mouth and tentacles facing upward
medusa
umbrella-shaped with mouths and tentacles downward
mesoglea
jellylike material that separates the two tissue layers of cnidarians
nematocyst
the stinging structures foun on both sea anemones and jellyfish
gastrovascular cavity
saclike digestive space in a cnidarians
flatworms are…
…simple bilateral animals
molluska are…
…diverse animals
annelids have…
…segmented bodies
flatworms (3 types)
planarians, flukes, tapeworms
complete digestive tract
consists of two openings (anus and mouth) at opposite ends of a continuous tube
radula
a filelike feeding organ
hemocoel
consists of spaces between cells within the animal’s tissues
segmentation
refers to the repeated sectinos of an annelid’s long body that contain a complex set of body structures
coelom
a fluid-filled space that is completely surrounded by muscle
roundworms shed their…
…stiff outer skeletons as they grow
many roundworms are…
…parasites
cuticle
made of chitin and must be shed whenever the animal grows larger
pseudocoelem
not completely lined by muscle
echinoderms have…
…radial symmetry
there are ___ classes of echinoderms
five
ossicle
interlocking calcium-based plates making up the internal skeleton of an echinoderms
water vascular system
a series of water-filled radial canals that extend along each arm from the ring canal surrounding the central disk
arthropod features are…
…highly adapted
arthropod exoskeletons serve…
…a variety of functions
arthropod diversity evolved over…
…millions of years
arthropod
an invertebrate animal with an exoskeleton made of chitin; a series of paired jointed appendages; and segmented body parts
exoskeleton
an external skeleton that supports the animal’s tissues against gravity
chitin
a long organic molecule made of sugars that is arranged in layers
appendage
an extension of an organism’s body
segmentation
describes how an arthropod’s body parts are divided into similar sections that have each evolved for a different function
arthropods (5 groups)
trilobites crustaceans chelicerates (arachnids) insects myriapods
crustaceans evolved as…
…marine arthropods
crustacean appendages can…
…take many forms
there are many different types of…
…crustaceans
crustaceans
a group of arthropods that have two distinct body sections, a hard exoskeleton
cephalothorax
the region of an organism in which the head and trunk region are combined into one long section
abdomen
rear portion of the organism
carapace
covers the sides of the body and protects the gills
mandibles
highly adapted appendages that crush and bite food before ingestion
arachnids are the…
…largest group of chelicerates
arachnids have evolved into a…
…diverse group
chelicerates
arthropods that lack antennae and have six pairs of appendages, which incle four pairs of walking legs
arachnids
a terresrial group of chelicerates characterized by eight legs, fanglike pincers that inject venom, and the ability to produce silk
book lungs
structures built of many thin, hollow sheets of tissue that look like the pages of a book
spiracles
tiny holes on the abdomen that open and close to allow oxygen to enter
tracheae
carry oxygen directly to the arachnid’s tissues
insects are the dominant…
…terrestrial arthropods
insects undergo…
…metamorphosis
insects have adapted to…
…life on land
incomplete metamorphosis
direct developmet
egg to nymph to adult
nymph looks similar to adult
complete metamorphosis
young insects do not look like adults but molt and change
egg to larva to pupa to adult
pupa
an inactive form of an insect
arthropods and humans share…
…many of the same resources
some arthropods cna spread..
…human diseases
insecticide
a chemical compound that kills insects and other arthropods
vector
an organism that carries a disease from one host to another
