Bio200-Mollusks

Front 1

adaptive radiation

Back 1

the evolution of an ancestral species into several new species within a relatively short period of time and in a certain geographic area

Front 2

phlyum mollusca

Back 2

100,000 living species, 35,000 extinct species...evolved 600mya

Front 3

Class Polyplacophora

Back 3

Chitons

Front 4

Class Pelecypoda

Back 4

clams, oysters, mussels, scallops

Front 5

Class Gastropoda

Back 5

snails, slugs, limpets, whelks

Front 6

Class Cephalopoda

Back 6

squid, nautilus, octopus

Front 7

Shell

Back 7

made of calcium carbonate, provides protection from predators

Front 8

Head

Back 8

has the "brain," the sense organs in the form of eyes or tentacles and a radula(a tongue like rasping organ with teeth)

Front 9

Mantle

Back 9

a lining of the body wall. Covers the body organs and produces the calcium carbonate of the shell

Front 10

Visceral Mass

Back 10

digestive, excretory, circulatory, reproductive organs. (refer to p. I3)

Front 11

Foot

Back 11

muscular, for locomotion (important for classification of mollusks into different classes)

Front 12

Gills

Back 12

located in pallial groove, which is between the mantle and foot. Have a large surface area for the diffusion of gases

Front 13

Radula

Back 13

a rasping tongue inside of the mouth used to scrape algae off rocks

Front 14

Esophagus

Back 14

short tube connecting mouth to stomach

Front 15

Stomach

Back 15

chamber where digestion continues as more enzymes are added and food is mixed

Front 16

digestive gland

Back 16

"liver"...large gland which adds digestive enzymes to food passing into the intestine. Found ventral to the gonad and has a smooth, green texture

Front 17

intestine

Back 17

looping tube extending from the stomach (refer to p. I8)

Front 18

gonad

Back 18

(a testis or ovary)...releases its gametes (egg or sperm) out of tubes which empty out gonopores into the pallial groove and are swept away

Front 19

bivalves

Back 19

consisting of two shells

Front 20

umbo

Back 20

dome shaped elevation on each valve, oldest part of shell. This points towards the anterior side of the organism

Front 21

Liver

Back 21

secrete enzymes and absorbs food products

Front 22

Incurrent Siphon

Back 22

short tube along ventral surface leading inside mantle between the 2 valves; water enters this way

Front 23

Excurrent Siphon

Back 23

short tube along the dorsal surface leading outside from the mantle between the 2 valves; water leaves this way

Front 24

Heart (Clam)

Back 24

A distinct structure with three chambers - two auricles and a ventricle. (refer to p. I14)

Front 25

Pharynx

Back 25

A muscular throat leading from the mouth containing a dorsal horny "jaw" and a ventral tongue-like radula

Front 26

Crop

Back 26

a large thin-walled storage chamber for food

Front 27

Ovotestes

Back 27

single gonad produces both eggs and sperm in different parts of the organs. Lies in the apex of the shell

Front 28

Oviduct

Back 28

On the female side, this tube carries eggs to the vagina

Front 29

Penis (snail)

Back 29

lies next to the vagina

Front 30

Dart Sac

Back 30

Unique to snails, a chamber adjoining the vagina. (refer to p. I19)

Front 31

Siphon(squid)

Back 31

(funnel lies near the head and is an extensio of the mantle cavity. (refer to p. I22)

Front 32

pen

Back 32

A translucent, flexible, thin blade of supporting tissue which runs along the back of the squid just under the mantle (refer to p.I22)

Front 33

ink sac

Back 33

Black colored sac, filled with fluid, lies above the rectum with an opening near the anus.

Front 34

caecum

Back 34

a large digestive side chamber; a long thin walled sac extending posterior from the stomach and caecum.

Front 35

kidney (squid)

Back 35

(=nephridium) one obvious excretory organ drains fluids from the pericardial chamber surrounding the heart and forms urine. The latter is eliminated via tubes in the mantle cavity

Front 36

gill hearts

Back 36

two accessory hearts (single chambers) just before the two gills which give blood an extra boost as they pass through the capillaries of these respiratory organs

Front 37

arms (squid)

Back 37

the squid foot is a circle of eight arms

Front 38

tentacles(squid)

Back 38

the squid foot is a circle of 2 tentacles with suckers

Front 39

girdle

Back 39

heavy mantle tissue that surrounds the 8 plates and in some cases covers them

Front 40

sense organs

Back 40

there are no distinct eyes nor tentacles in chitons. the mantle is sensitive to touch, chemicals, and light

Front 41

Adductor muscles

Back 41

broad and powerful muscles located near the hinge. control opening and closing of the shells

Front 42

labial palps

Back 42

soft fleshy flaps that bring food into the mouth

Front 43

albumen gland

Back 43

on the female side, this gland provides nourishment for the eggs

Front 44

vas deferens

Back 44

on the male side this tube lies parallel to the oviduct. sperm passes through this tube on the way out the penis

Front 45

chromatophores

Back 45

the dark spots, found on the mantle, are pigment cells that allow squid to change their color instantly

Front 46

eye (squid)

Back 46

Capable of adjusting focus and the pupil can be dilated or contracted to respond with changes in light

Front 47

brain

Back 47

collection of fused ganglia

Front 48

hinge

Back 48

dorsal side; unites the right and left valves

Front 49

growth rings

Back 49

outside of the shell, similar to the rings seen in a cross-section of a tree trunk. Each ring represents a period of rapid growth followed by a period of rest

Front 50

tentacles (snail)

Back 50

there are two pairs, act as touch, taste, and olfactory (smell) detectors

Front 51

lung

Back 51

chamber formed by the mantle cavity for oxygen and carbon dioxide exchange. (refer to p. I18)

Front 52

jet propulsion

Back 52

method of locomotion; refer to p. I20

Front 53

soft-bodied

Back 53

all mollusks, (boneless)