Summary: Animals of the Intertidal Zone

Question 1

The phylum Echinodermata means ___ ___

Answer 1

spiny skin

Question 2

Echinodermata have ___ symmetry

Answer 2

pentaradiate (5-fold)

Question 3

Echinodermata have a water vascular system (WVS) which is a hydraulic _____. How do they use this?

Answer 3

skeleton!
Use water-filled tubes to walk, feed, and for defense

Question 4

Echinodermata have an __skeleton made up of __ ___.

Answer 4

endoskeleton (internal- skin covers the spines)
calcium carbonate

Question 5

Sea urchins and sand dollars have ____, covered by skin because they have an endoskeleton

Sea stars and cucumbers have ___ embedded in their body wall (endoskeleton)

Answer 5

spines
ossicles

Question 6

What are ossicles and which intertidal animal has them?

Answer 6

small calcareous elements embedded in the dermis of the body wall of echinoderms. They form part of the endoskeleton and provide rigidity.

sea stars

Question 7

What is mutable collagenous tissue? What phylum of animals has it?

Answer 7

MCT is collagen that can stiffen or soften by nervous input; found in echinoderms (eg sea stars)

Question 8

What does mutable collagenous tissue do?

Answer 8

In echinoderms, it is used to lock spines in place, lock skeleton for leverage, or to autonomize arms or spines

Question 9

What are the 5 classes of echinoderms?

Answer 9

• sea stars
• sea cucumbers
• sea urchins
• brittle stars
• crinoids

Question 10

how do sea stars feed?

Answer 10

They feed by using water vascular system (WVS) with mutable collagenous tissue (MCT) to lock their skeleton
- then pull valves apart to insert their cardiac stomach and digest the animal extracellularly

Question 11

How do sea cucumbers feed?

Answer 11

Deposit or suspension feed with modified tube feet at mouth

Question 12

How do sea urchins feed?

Answer 12

They graze algae with 5 teeth in their Aristotle’s lantern

Question 13

What is the Aristotle’s lantern found in sea urchins?

Answer 13

A structure of 5 teeth held and moved by muscles

Question 14

What are the 3 characteristics found in all classes of echinoderms?

Answer 14

1. pentaradiate symmetry (5)
2. Hydrostatic skeleton (water vascular system) “tube feet”
3. calcium carbonate skeleton (plate/ ossicles)

Question 15

How do brittle stars feed?

Answer 15

Deposit or suspension feed with tiny tube feet on their arms

Question 16

How do crinoids feed?

Answer 16

suspension feed using modified tube feet to catch particles from water

Question 17

The phylum Arthropoda means “___ ___”

Answer 17

jointed legs

Question 18

Need to know 2 groups of arthropods:
1:
2:

Answer 18

1. Decapoda (crabs): 10 (walking) legs
2. Cirripedia (barnacles): “settle on head” feet become feeding appendages

Question 19

Decapods have an exoskeleton made of ____ that is hardened (sometimes hardened with ___)
- They ___ their skeleton to grow: produce the hormone ___ to do this

Answer 19

chitin
calcium

molt
ecdysone

Question 20

What are the 2 body regions of crabs (decapods)?

Answer 20

1. thorax (head/ stomach)
2. abdomen (tail tucked under body)

Question 21

What are some things that crabs eat?

Answer 21

snails, other crabs, deposit feed using setae on claws, filter feed using setae on antennae

Question 22

Crabs can filter feed using the ___ on their ____

They can also deposit feed using the ____ on their ___

Answer 22

filter: setae on antennae
deposit: setae on claws

Question 23

Crab claws and legs have many sensory ___ that detect __ and ___ in the water

Answer 23

setae

chemicals and vibrations

Question 24

How do barnacles (Cirripedia) feed?

Answer 24

they have cirri- arthropod feed that have setae and rake the water to capture particles
“settle on head”

Question 25

The body of barnacles is usually ___, except in goose neck barnacles which have a ___ ___

Answer 25

calcified muscular stalk

Question 26

the calcified body of barnacles resists ___ and ____ Therefore barnacles can live at highest high tidelines

Answer 26

desiccation and predation

Question 27

Which animal can live at the highest high tidelines?

Answer 27

barnacles

Question 28

Phylum Mollusca includes classes ___, ____, ____ and ____

Answer 28

cephalopods, gastropods, bivalves, chitins

Question 29

Gastropods are a class of ____, and their name means "___-___"

Answer 29

Mollusca stomach-foot

Question 30

___ are a shelled mollusc with a __/__ region and a __/___ region

Answer 30

snails head/ foot stomach/ shell

Question 31

gastropods are characterized by a "creeping ___", and their shell is secreted by the ____

Answer 31

creeping foot mantle

Question 32

t/f the mantle is a basic characteristic for all molluscs

Answer 32

true

Question 33

How do gastropods feed? What do they eat? List 2 different types

Answer 33

Some graze on algae using a radula (a ribbon of teeth that is pushed out of the buccal cavity (mouth) and rasps the food Others (called 'drills) drill into the shells of other snails and bivalves and eat them

Question 34

____ are gastropod molluscs with 8 plates that make up a protective shell. They typically lie flat on a rock and graze ___, but some are ____

Answer 34

chitons algae carnivorous

Question 35

_____ molluscs have a shell that's formed into 2 sides that close together at a hinge (using strong ___)

Answer 35

bivalve muscles

Question 36

How do bivalve molluscs feed?

Answer 36

inside the valves are gills- they use ciliary mucus filter feeding

Question 37

In bivalve molluscs, the shell is secreted by the ___, which forms 2 siphons. What do these siphons allow for?

Answer 37

mantle 2 siphons to allow water into the space between the valves

Question 38

The main characteristic of the phylum cnidaria is their ability to ___ (using the ___)

Answer 38

sting cnidocyst

Question 39

Anthozoans are commonly known as ___ and are part of phylum ____

Answer 39

anemones cnidaria

Question 40

T/F Anthozoans (anemones) have no medusa stage

Answer 40

true

Question 41

Anthozoans (anemones) are - soft or hard bodied - sessile or mobile - ___ shaped - in the nemertea/ cnidaria phylum

Answer 41

soft sessile sac-shaped cnidaria

Question 42

anemones have: - tentacles with ____ - a ____ cavity - ____ to wipe stinging cells onto neighbors to fight

Answer 42

cnidocytes gastrovascular acrorhagi

Question 43

Explain how anemones use their tentacles to sting

Answer 43

The tentacles have stinging cells called cnidocytes that contain stinging organelles called cnidocysts

Question 44

- Anemones can have different cnidocysts for diff _____ and also different ____ ____ - some cnidocysts ___ their prey while some are ____ and hold onto shell bits to protect the anemone from_____

Answer 44

species body regions pierce sticky desiccation

Question 45

Cnidocyst vs cnidocyte?

Answer 45

Cnidocytes are the stinging cells attached to tentacles, while cnidocysts are the stinging organelles on the cnydocyte

Question 46

t/f sea anemones cannot swim away from predators

Answer 46

false, some of them can! Some can't, so they just sting

Question 47

What are acrorhagi?

Answer 47

A region of cnidocysts on anemone tentacles- the anemones use acrorhagi to wipe stinging cells onto neighbors to fight

Question 48

The phylum Nemertea means ___ because they're very accurate ___

Answer 48

unerring (ie always right/ accurate) predators

Question 49

The Nemertea phylum consists of ___ worms which have special ____ allowing them to stretch very ___

Answer 49

ribbon muscles long

Question 50

Ribbon worms have a muscular mouth cavity called a ____. How do they eat?

Answer 50

Rhyncocoel The phyncocoel shoots out a dart (stylet) to harpoon prey

Question 51

What do Nemerteas eat?

Answer 51

Nemerteas (ie ribbon worms) eat other worms and small crustaceans

Question 52

What is a rhyncocoel?

Answer 52

a muscular mouth cavity that ribbon worms have; they use it to shoot out a dart and harpoon their prey

Question 53

The phylum Platyhelminthes consists of ____

Answer 53

flatworms platy= flat helminthes= worm

Question 54

how big are flatworms?

Answer 54

small! <1cm to 5cm very very flat

Question 55

t/f platyhelminthes do not have a body cavity

Answer 55

true!

Question 56

How do flatworms feed?

Answer 56

They don't have a body cavity, so they feed with a pharynx that is ciliated and can crawl into prey

Question 57

What do flatworms eat?

Answer 57

barnacles, tunicates, etc (crawl inside them to ingest)

Question 58

The phylum "annelida" means ___ worms

Answer 58

segmented ie rings (they have segments that look like rings)

Question 59

Polychaetes are segmented worms with many ____

Answer 59

setae poly=many chaetes= setae

Question 60

Annelids have muscular ____ for biting/ grazing and specialized appendages for ___ or ___

Answer 60

jaws walking or respiration

Question 61

How do some annelids feed?

Answer 61

Some secrete tubes and filter feed with tentacles

Question 62

Do hydrothermal vent worms filter feed in the same way that some annelids do?

Answer 62

No! Vent worms do not filter feed, they have symbionts for chemosynthesis

Question 63

List 3 other encrusting animals under rocks

Answer 63

1. bryozoa 2. sponges 3. ascidians

Question 64

Bryozoa: - are a phylum of "__" animals - have a feeding organ called a ______ which is a horseshoe-shaped structure with ____ that creates a filter feeding current

Answer 64

moss lophophore cilia