Animal Groups

Question 1

What are the 7 most common animal groups?

Answer 1

Sponges

Cnidarians

Mollusks

Lophophorates

Echinoderms

Chordates

Arthropods

Question 2

What are sponges?

Answer 2

Most archaic form of animal

They consist of simple cells held together by an animal protein called collagen

Also have spiny pieces called Spicules

Hollow with a central cavity lined with cells that generate a current and trap food

Question 3

What animals are grouped up to be Cnidarians?

Answer 3

Sea Anemones, Jellyfish, and all types of coral

Question 4

What are Cnidarians?

Answer 4

The first to have true tissues

All have a sac like body with a jelly like fluid consisting mostly of water

Question 5

What do Cnidarians have to catch prey?

Answer 5

Stinging cells on their tentacles, small barbed whip loaded with toxins that penetrate prey

Question 6

What are the living portions of coral reefs?

Answer 6

Polyps, resemble small sea anemones that inhabit the cavities within the coral skeleton

Question 7

What is so unique about corals compared to other cniderians?

Answer 7

Tend to be better preserved as fossils since they are the only cnidarian to have a skeleton made of calcite

Question 8

What animals are grouped up to be Mollusks?

Answer 8

Shell-building animals, like Snails, Clams, Octopus, and Squid

Question 9

What do all mollusks have?

Answer 9

A muscular foot as well as a fleshy mantle used for making a shell

Question 10

What are the three major groups of Mollusks and what animals are in them?

Answer 10

1) Bivalves (two valves) : CLAMS, SCALLOPS, OYSTERS

2) Gastropods (stomach-foot) : SNAILS, SLUGS

3) Cephalopods (head-foot) : OCTOPUS, SQUID

Question 11

What does the muscular foot in bivalves do? What about for Gastropods, Cephalopods too?

Answer 11

Muscular foot usage:

Bivalves - Shaped like a blade and is used for burrowing into sediment, can swell into an anchor

Gastropods - Used to glide, muscular foot is their stomach

Cephalopods - Been modified into grasping tentacles, foot extends from their head hence (head-foot)

Question 12

What do squids and octopus have that no other mollusk has?

Answer 12

Have an internal shell/skeleton

Question 13

What makes up squid and octopus shells/skeleton?

Answer 13

CARBOHYDRATE CHITIN

Question 14

What did some ancient cephalopods have? (Hint: Like the modern shelled Nautilus)

Answer 14

Large spiral shell made out of calcite

Question 15

What animals are grouped into Lophophorates?

Answer 15

Shell-building BRACHIOPODS and the colonial BRYOZOANS

Question 16

What makes a lophophorate a lophophorate?

Answer 16

Based on the presence of a structure called a lophophore, a tentacle-covered feeding organ

Question 17

What animals are grouped into Arthropods?

Answer 17

CRABS, LOBSTERS, SHRIMP, BARNACLES, SPIDERS, INSECTS, and TRILOBITES

Question 18

What is the commonality between all Arthropods?

Answer 18

All have jointed legs and a segmented body

Exoskeleton made out of chitin, this is essential for movement (allows the attachment of muscles

Question 19

What defines the type of arthropod a specimen is?

Answer 19

Their 1 of 4 basic body plans

More than 10 legs - Millipede

10 legs - Crustacean

8 legs - Arachnids

6 legs - Insect

Question 20

What is unique about exoskeletons?

Answer 20

They DO NOT Grow once built, they must molt in order to make a new one when they outgrow it

Question 21

What animal is an arthropod but was once originally mistaken as a mollusk?

What so unique about them?

Answer 21

Barnacles

ONLY ARTHROPOD TO MAKE A SHELL OUT OF THE MINERAL CALCITE

Has a strong biological glue that keeps them stuck

Question 22

What are grouped into Echinoderms?

Answer 22

Starfish, Sea urchins, sea cucumbers, brittle stars, and crinoids

Question 23

What is the commonalty between all echinoderms?

Answer 23

ALL HAVE A 5-FOLD SYMMETRY

Question 24

What are the skeletons of Echinoderms called? What are they?

Answer 24

They are called “test”

Overlapping calcite plates connected by muscle

Question 25

How do all echinoderms move? With the help of what?

Answer 25

They all have tube feet with suction cups that are used for movement

Can grab onto objects and prey

Question 26

What are the similarities between starfish and sea urchins?

Answer 26

Sea urchins are really nothing more than a starfish bent backwards and fused together

Tube feet face outward instead of downward

Question 27

What are the similarities between sea urchins and sea cucumbers?

Answer 27

Sea cucumbers are really just sea urchins that have been turned sideways and stretched out

SEA CUCUMBERS HAVE A HEAD AND TAIL

Question 28

What are the similarities and differences between Crinoids and Brittle starfishes?

Answer 28

Both have similar lifestyles and delicate arms

CRINOIDS LIVE ON A STEM

BRITTLE STARS CAN FREELY MOVE AROUND

Question 29

What animals are grouped of with chordates?

Answer 29

Majority of large animals

Tunicates, Fishes, Amphibians, Reptiles, Birds, Mammals

Question 30

What is the commonality of all chordates?

Answer 30

ALL have a spinal cord, “backbone”, gill slits, and a bony or cartilaginous tail

Have been modified in other chordates