EPS SCI 15 - Lab 8 Study Deck

EPS SCI 15, Spring 2026

Periwinkle Snail: Intertidal Zone

Spray to High Tide

Periwinkle Snail: Avoiding Desiccation

Cementation with mucus, water reservoir inside shell

Periwinkle Snail: Staying Attached

Vacuum suction by muscular foot, mucus

Abalone, Mussel: Intertidal Zone

Middle Tide

Abalone, Mussel: Avoiding Desiccation

Closes shut, water reservoir in shell

Abalone, Mussel: Staying Attached

Flexible Cement, 2: organic threads

Limpets: Intertidal Zone

Spray to High Tide

Limpets: Avoiding Desiccation

Create suction (using muscular foot), mucus

Limpets: Staying Attached

Vacuum suction by muscular foot, mucus

Shore Crab: Intertidal Zone

All

Shore Crab: Avoiding Desiccation

Store water in gill chambers, seek cool shaded moist environments during day

Shore Crab: Staying Attached

Leverage between rocks or in crevices

Sea Anemone: Intertidal Zone

Low Tide

Sea Anemone: Avoiding Desiccation

Close up tight, retract tentacles and mouth, mucus, cover themselves (shells, sand, algae)

Sea Anemone: Staying Attached

Suction, mucus, central food disc

(Some) Crustation: Avoiding Desiccation

Seek cool shaded moist environments during day

Sea Urchin: Intertidal Zone

Low Tide

Sea Urchin: Avoiding Desiccation

Close up tight, retract tentacles and mouth, mucus, cover themselves (shells, sand, algae)

Sea Urchin: Staying Attached

Vacuum suction by small tube feet, mucus, boring into rock

Sea Star: Intertidal Zone

Low Tide

Sea Star: Avoiding Desiccation

Physiological adaptation, high tolerance

Sea Star: Staying Attached

Vacuum suction by small tube feet, mucus

Determines upper limit of organisms in each zone

Physical Conditions

Physical Conditions

Waves, Exposure time, Temperature, Substrate Type, Space

Determines lower limit of each zone

Biological interactions

Biological Conditions

Predation, Competition (Space), Adaptation

Sea stars eat (1), Sea otters eat (2), Sea urchins eat (3)

mussels, sea urchins, kelp

Barnacles are what type of organism?

Crustation

Starfish and sea urchins are…

echinoderms

Which organisms are echinoderms?

sea star/starfish, sea urchins

Echinoderm characteristics

Radial symmetry, spine in skin

Macroalgae are plants.

False

G/B/R Algae: Closest to terrestrial plants

G

G/B/R Algae: Can kill coral reefs

G

G/B/R Algae: Create Kelp Forests

B

G/B/R Algae: Largest

B

G/B/R Algae: Most structurally complex

B

G/B/R Algae: Use pneumatocysts to keep its fronds upright

B

G/B/R Algae: Is best at absorbing light in deeper water

R

G/B/R Algae: Use CaCO3 to support its structure

R

Higher or Lower: Mostly Shelled Organisms

Higher

Higher or Lower: Many soft-bodied organisms and algae

Lower

Macroalgae: Holdfast

Roots

Macroalgae: Stipe

Stem

Macroalgae: Pneumatocyst

Ball filled with gas, keeps kelp upright

Macroalgae: Blade

Leaves, perform photosynthesis