Biology Chapter 26

sponges

Phylum Porifera (pore-bearer)

filter feeding

method in which food particles are filtered from water as it passes by or through some part of the sponge

osculum

A large opening on a sponge through which filtered water and wastes are expelled

pore cell

allow water carrying food and oxygen into the sponge's body

epithelial cell

thin and flat/contract in response to touch or irritations causing pore cells to close up

collar cell

flagellated cells that line the inner cavity of a sponge, which helps draw water through the pores

amoebocytes

located between the 2 cell layers/carry nutrients to other cells/aid in reproduction/produce chemicals that help make up spicules

spicules

small, needle-like that form the hard support system of sponges

hermaphrodite

animal that can produce both eggs and sperm/most sponges fall into this category

external fertilization

eggs and sperm are both released into the water/fertilization occurs outside the body/fertilization in a few sponges occurs this way

internal fertilization

eggs remain inside the body; sperm are carried to the eggs in the flow of water/most fertilization in sponges occurs this way sponges

cnidarians

Phylum meaning "stinging cells"/jellyfish, corals, sea anemones, and hydras

asconoids

sponges with a vase-like structure with a central cavity

syconoids

sponges with a tubular body with folds inside the body wall

leuconoids

sponges with an interconnected system of complex canals and chambers

encrusting sponges

sponges that grow by spreading over the ocean floor and forming a hard surface

boring sponges

type of sponges that bore thin channels through calcium carbonate/rocks

erect sponges

sponges that grow upright in the water, often building stem-like structures

sclereocytes

cells in sponges that secrete spicules

archeocytes

large cells that take up food particles by engulfing them/allow sponges to regenerate themselves

choanocytes

flagellated cells that create a water current to bring in water through pores and pump it around the sponge canals

sponge crab

attaches sponges to its back for camouflage/the sponge gets carried around to good food sources/mutualism

radial symmetry

Symmetry about a central axis/cnidarians' body structure

hexactinellida

glass sponges/live in the deep

Carnivorous Demosponges

have hooks that catch small fish or crustaceans as prey/harp sponge is one type

demosponges

are by far the largest group of sponges/live in the deep and the shallows

calcarea sponges

calcium carbonate spicules/restricted to life in the shallows

polyp

The sessile, tubular form of a cnidarian with a mouth surrounded by tentacles

medusa

A free-swimming cnidarian with a bell-shaped/umbrella-shaped body and tentacles hanging downward

nematocyst

In cnidarians, a stinging cell that is used to inject a toxin into prey

gastrovascular cavity

A central cavity with a single opening in the body of certain animals, including cnidarians and flatworms, that functions in both the digestion and distribution of nutrients.

nerve net

simple nervous system of cnidarians which conducts nerve impulses from all parts of the body/there is no control center

Hydrozoa

class that includes the hydroids (the hydra) and the siphonophores (Portuguese man-of-war)

Scyphozoa

class that includes jellyfish

Anthozoa

class that includes sea anemones and coral/exhibit only polyp form

sea anemones

anthozoans that live as individual animals

coral

anthozoans that live in colonies of polyps

flatworms

Phylum Platyhelminthes/parasitic worms with bilateral symmetry

parasitic tapeworm

flatworm in the class Cestoda

fluke

flatworm in the class Trematoda

pharynx

digestive organ in flatworms/begins to digest food outside the flatworm then sucks the food into the gastrovascular cavity

eyespots

sensory structure that determines intensity and direction of light

flame cells

specialized cells that remove excess water from the body (flatworms)

regeneration

The ability to regrow a missing part of the body

body of a tapeworm

scolex and proglottids

scolex

head of an adult tapeworm; can contain suckers or hooks

proglottids

body sections of a tapeworm/contains muscles, nerves, flame cells, and male and female reproductive organs

roundworms

Phylum Nematoda

ascaris

mainly infects children/eggs hatch in intestines, move to the bloodstream,move to the lungs, are coughed up and swallowed; cycle starts again

hookworms

usually enter the body through bare feet and move through the body to the small intestines where they attach themselves with a series of hooks around their mouths.

pinworms

most common type of roundworm/Identified by itching of the anus where eggs are laid

trichinella

enter the body through undercooked pork

nematodes

roundworms that infect and kill pine trees, cereal crops, and food plants