aquatic protists
what animals most likely evolved from
multicellular heterotrophs
must get food from other organisms to survive
collagen
what animal cells are supported by
diploidy
two copies of each chromosome (half from each parent)
homeotic genes
genes that control early development in animals
vertebrates
with a backbone
invertebrates
without a vertebrate
body plans
an animal's shape, symmetry, and internal organization
symmetry
arrangement of body structure
asymmetry
when the two sides are not mirror images of one another (irregular shape); ex: sponge
radial symmetry
body parts arranged around a central axis like spokes on a bicycle wheel; ex: sea anemone
bilateral symmetry
distinct right and left halves, dies are mirror images; ex: humans
anterior
head end of animals
posterior
tail end of animals
dorsal
back surface of animals
ventral
belly surface of animals
cephalization
the development of a head end with a concentration of nerves and sensory structures (leads to the development of the brain)
ectoderm
outer, primary tissue later
mesoderm
middle, primary tissue layer
endoderm
inner, primary tissue layer
skin, hair, finger nails, brain, spinal cord, nerves
ectoderm gives rise to....
heart arteries, veins, muscles, kidneys, bladder, reproductive organs, most of the skeleton
mesoderm gives rise to....
lungs, stomach, intestines, gallbladder, pancreas, esophagus, colon
endoderm gives rise to...
triploblastic
animals with bilateral symmetry and 3 tissue layers
digestion
break down of food
gastrovascular cavity
appears in simple animals, digestive cavity with only 1 opening
digestive tract (gut)
appears in complex animals, has 2 opening, a mouth and anus
protostomes
less complex animals, mouth develops first, anus develops second
deuterostomes
more complex animals, anus develops first, mouth develops second
hydrostatic skeleton
water in a closed cavity that presses against the soft body providing support; ex:earthworm
exoskeleton
hard covering one the outside of the body that provides the framework for support and protects soft body; ex: crab
endoskeleton
internal skeleton composed of her material that provides support; ex: human backbone
recognition
ability to recognize of the same type
sessile
permanently attached to surfaces
secrete toxic substances that prevent other sponges from growing into their area as will protect them from hungry predators
the way that sponges protect themselves
hermaphrodites
contain both male and female reproductive organs
ostia
tiny opening in the body wall of a sponge where water enters
spicules
tiny needles for support made by silica
oscula
large opening at the top of the sponge where water exits
collar cells
flagellated cells that beat back and forth drawing water into the sponge
collar cells create a current that is pulled in through the ostia
the way that water is drawn into the sponge
gastrovascular cavity (1 opening), water carries wastes away out the oscula
the way that a sponge gets rid of waste
ameobocytes (mobile cells) move around transporting nutrients, oxygen, and wastes
the way that the sponge supplies its cells with nutrients
medusa
a type of cnidarian, free floating, umbrella shape with tentacles and mouth underneath
polyp
a type of cnidarian, tubelike, attached to the surface with tentacles and mount on top
mesoglea
jellylike material in cnidarians that separates the ectoderm from the endoderm
cnidocytes
stinging cells on the end of tentacles used for defense and capturing prey
nematocyst
small hooks used to spear prey (defense)
planarians
class of platyhelminths, free living, nonparasitic, head with eyespots and simple brain, actively hunt for food using chemoreceptors to detect odors in the water or air
flukes
class of platyhelminths, parasites that feed on the body fluids of other animals, can be contracted by wading in or drinking water that contains their larvae
tapeworms
class of platyhelminths, parasites that live in the gut of vertebrates, have no gut; absorb nutrients from the digested food in which they live
cuticle
tough exoskeleton of roundworms, made of chitin, must shed in order to grow larger
pseudoceolom
a partially enclosed cavity, circulates substances in a nematode
hookworms
type of roundworm, live in digestive tract of host and enter the body by burrowing through bare feet
pinworms
type of roundworm, found in the gut of hosts, gain entrance when eggs are accidentally swallowed off contaminated surfaces
guinea worms
type of roundworm, live in guts & connective tissues of hosts, enter when host drinks contaminated water
(most) bilateral
symmetry that mollusks exhibit
visceral mass
center that holds organs (1 way gut) in mollusks
mantle
heavy fold of tussle that covers the internal organs in mollusks
foot
muscular region used for locomotion in mollusks
excretion
removal of metabolic waste
radula
file- like feeding organ used to scrape food fragments off rocks
gastropoda
class of mollusks that snails and slugs belong to
bivalves
class of mollusks that oysters and mussels belong to
cephalopods
class of mollusks that squids, octopus, and cuttlefish belong to
annelids
phylum that earthworms, fireworms, and leeches belong to
coelom
body cavity entirely within the mesoderm
cerebral ganglion
primitive brain located in the anterior segment connected to a nerve cord that runs along the underside of the worms body
setae
external bristles that increase traction for crawling
hydrostatic skeleton
type of skeleton that annelids have
3/4
amount of animals that are arthropods
crustaceans
group of arthropods that includes shrimp, lobster, and crabs
arachnids
group of arthropods that includes spiders, mites, scorpions and ticks
insects
group of arthropods that includes bees, grasshoppers, and butterflies
molting
when insects shed or discard their exoskeleton in order to grow
appendage
structures that extend from the arthropod's body wall
segmentation
body parts divided into similar sections with specific functions
cephalothorax
head and trunk region combined into one long region
abdomen
rear portion of the organism
malpighian tubules
tubules that extend from the arthropod's gut transporting wast particles to be excreted from the body
spiracles
when air enters the body in arthropods
tracheae
where respiration occurs in arthropods
vector
an organism that carries disease from one host to another
8
number of legs that arachnids have
6
number of legs that insects have
4 per segment
number of legs that millipedes have
2 per segment
number of legs that centipedes have
97%
percentage of animals that are invertebrates
arthropods
phylum that makes up 86% of invertebrates
body plans, tissue layers, digestion, support
characteristics that animals are categorized by
phylum porifera
oldest evolutionary group of animals
sponges
common name for phylum porifera
five- part radial
symmetry of echinoderms
endoskeleton
skeleton of echinoderms
water- vascular system
series of water filled canals in each arm of echinoderms
contains mouth, stomach, small intestine, and arms
digestive tract of echinoderms
invertebrate chordate
completely internal skeleton, develop a notochord, pharyngeal gill slits and a post anal tail at some point in their life
notochord
a flexible, dorsal rod
pharyngeal gill slits
openings that develop into the wall of the pharynx
pharynx
the muscular tube that connects the mouth to the digestive tract and windpipe
notochord
...