Bio Lab 10 - Mollusks

Question 1

Phylum Mollusca

Answer 1

4 Part Body Plan
4 Classes
Includes snails, squids, octopus, clam, ec

Question 2

Mollusk Body Plan

Answer 2

1. Mantle: Secretes a shell (if have one)
2. Mantle Cavity: houses ctenidia
   - Ctenidia: absorbs water, nutrients, gill-like
3. Foot: locomotion and prey capture
4. Visceral Mass: internal organs and coelom (space around organs)

Question 3

Classes of Phylum Mollusca

Answer 3

Polyplacophora- Chitins
Bivalvia - 2 valves (clams)
Gastropoda - stomach feet (snails)
Cephalopoda - head feet (squid, octopus)

Question 4

Class Polyplacophoroa

Answer 4

of Phylum Mollusca

• 8 CaCO3 plates
• covered in colored membranes
• see picture of body struture

Question 5

Class Bivalvia

Answer 5

• 2 Doors (like shells)
• scallops, oysters, clams
• filter feeders
• water flows over gills then anus
• clam dissection

Question 6

Class Gastropoda

Answer 6

• stomach feet
• snails, slugs, nudibranches
• see snail reproduction
• radula for scraping food
• snail dissection

Question 7

Snail Reproduction

Answer 7

1. “Male” shoots Love Dart out of Common Gonopore (CG)
2. Love dart penetrates Dart Sac
3. Male’s Flagellum leaves out CG and into CG of female
4. Flagellum deliver Sperm Packet
5. Packet travels up Spermathecal Duct
6. Packet stored in Spermatheca
7. If female chooses, the sperm is wrapped around eggo yolk, surrounded by egg white and shell and dropped out CG to environment
8. Egg and sperm made in Ovitestes

Question 8

Class Cephalopoda

Answer 8

-squid, cuttlefish, octopus
Squid:
-8 arms, 2 tentacles
-Jet propulsion through mantle cavity
-Ink sac smoke screen
Chromatophores: change color and texture
Squid dissection

Question 9

Dissections of Mollusks

Answer 9

1. Clam: Class Bivalvia
2. Snail: Class Gastropoda
3. Squid: Class Cephalopoda

Question 10

Clam Dissection

Answer 10

See Figure 7 from lab book
Parts to know:
-mantle
-mantle cavity
-siphons
-gills
-foot
-visceral mass
-labial palps: on sides of the foot
-mouth
-stomach
-digestive gland: green
-gonad tissue: tan
-intestine
-heart
-anus

Question 11

Snail Dissection

Answer 11

Compare picture off phone to picture from lab book
Parts to know:
-Dart sac is huge
-Spermaovaduct looks like a brain
-Spermathecal duct is long, spindly, tangled
-Vagina is small, found at fork by dart sac
-Common gonopore
-Penis

Question 12

Squid Dissection

Answer 12

-See figure 13