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57 terms

Apex Biology - 8.4

Invertebrates
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vertebrate
Animal that has a backbone.
invertebrate
Animal that doesn't have a backbone.
annelid
Worm with cylindrical, segmented bodies.
arthropod
Invertebrate with segmented body and jointed limbs, such as spiders and insects.
cnidarian
Aquatic animal that has a saclike body with stinging tentacles.
echinoderm
Aquatic animal, such as sea urchin or starfish, which have spiny skin.
mollusk
Aquatic animal that has a soft body surrounded by a hard outer shell.
radial symmetry
A body plan in which the organs and tissues are arranged in a circle around a central axis.
bilateral symmetry
A body plan in which two halves of the body are mirror images of one another.
blastula
The early stage of an embryo that is composed of a hollow ball of cells.
protostome
A bilaterally symmetrical invertebrate whose blastophore forms into a mouth.
blastophore
Opening of the blastula.
deuterostome
A bilaterally symmetrical invertebrate whose blastophore forms into an anus.
collar cells
Specialized cells that push water through sponges and pull food from the water.
osculum
An opening in the top of the sponge through which water exits
cnidocyte
Stinging cell that lines cnidarian tentacles.
nematocysts
Poison-filled structures in the tentacles of cnidarians.
medusa
The umbrella-shaped form of the cnidarian that can float freely in the water.
polyp
A cylinder-shaped cnidarian that attaches to objects on the ocean bottom and remains sedentary.
tripoblastic
Organisms that emerge from three cell layers.
coelom
A fluid-filled cavity that forms between the tissues.
acoelomates
Animals that lack a coelom.
hermaphrodite
An animal that has both male and female reproductive organs.
septum
A wall that divides the segments of a worm
trochophore
The larval stage of the mollusk.
radula
A rough, tongue-like organ in mollusks that is used for eating food.
mantle
A layer of tissue surrounding the mollusk's body that produces the shell.
visceral mass
A layer underneath the mantle which contains the mollusk's internal organs
exoskeleton
The hard material on the outside of invertebrates, used for protection and support
chitin
A polysaccharide component of the arthropod exoskeleton
molting
The process of shedding of the outer skin as the animal grows
tracheal tube
Tube that runs through an arthropod body and enables breathing
Malpighian tube
Tube that collects wastes from the arthropod's body for removal.
pupa
The stage at which an insect transforms into its adult form
decapods
Group of crustaceans that have ten (five pairs) feet.
chelipeds
Specialized legs used for catching prey.
carapace
A hard protective coating on the back of an animal.
thorax
The middle part of the body in an arthropod between the head and abdomen.
swimmerets
Appendages used for swimming.
arachnid
Arthropod that breathes air and has four pairs of legs.
chelicerae
Fang-like appendages near the mouth of an arachnid used to inject the prey with a paralyzing venom.
chelicerate
An animal that has chelicerae.
spinnerets
Organs in the spider that contain silk glands.
pedipalps
Appendages near the mouths of ticks, spiders, and other arachnids used to latch onto prey.
myriapod
Any arthropod that has an elongated body composed of many segments, such as the centipede and millipede.
endoskeleton
An internal skeleton
madreporite
A structure in the echinoderm through which water enters the vascular system.
ampulla
Bulb-like sacs in the echinoderm vascular system that are contracted to push the water through the canals into the foot.
schistosomiasis
A disease caused by the parasitic schistosome flatworm.
trichinosis
A disease caused by the parasitic roundworm Trichinella, which lives in meat.
malaria
A disease caused by microscopic parasites and transmitted through the bite of an infected Anopheles mosquito.
Lyme disease
A disease caused by bacteria transmitted by the bite of a deer tick that causes muscle and joint aches.
invasive species
Animals that are relocated from their native ecosystem to other parts of the world.
trilobite
A now extinct class of arthropod.
cephalization
The concentration of sense organs in the front of an animal's body.
ganglia
In some invertebrates, a structure made up of nerve cells; in mammals, a group of nerve cell bodies.
spiracles
Small openings through which air enters and exits the body of arthropods.