Sponges and Cnidarians
Most sponges are described as asymmetrical. What does this mean about their body shape?
A) They have two identical halves
B) They have no definite shape and cannot be divided into identical parts
C) They have parts arranged around a central point
B) They have no definite shape and cannot be divided into identical parts
Flatworms have very simple bodies. What is a key characteristic of their shape?
A) They are shaped like a long, smooth cylinder
B) They are flat and thin, like a piece of ribbon
C) They are made of many tiny repeating rings
B) They are flat and thin, like a piece of ribbon
Most mollusks have a hard outer ________ for protection and a broad, muscular ________ used for movement.
A) Shell and foot
B) Exoskeleton and wing
C) Skin and tentacle
A) Shell and foot
All arthropods have a hard outer covering that protects their bodies. What is this called?
A) Endoskeleton
B) Exoskeleton
C) Backbone
B) Exoskeleton
How many legs does an adult insect have?
A) Four legs
B) Six legs
C) Eight legs
B) Six legs
Sponges are filter feeders. How do they get the food they need to survive?
A) They use tentacles to pull fish into a central mouth
B) They strain tiny food particles from water as it moves through their pores
C) They move along the ocean floor to find decaying plants
B) They strain tiny food particles from water as it moves through their pores
Many flatworms and roundworms are parasites. What is a parasite?
A) An animal that makes its own food from sunlight
B) An organism that lives on or in a host and hitches a ride for food
C) A predator that hunts and eats other animals
B) An organism that lives on or in a host and hitches a ride for food
Which group of mollusks includes animals like snails and slugs that typically have a single shell or no shell at all?
A) Bivalves
B) Gastropods
C) Cephalopods
B) Gastropods
Which of these is a physical characteristic shared by all arthropods?
A) Jointed appendages (legs)
B) Internal lungs
C) Soft, slimy skin
A) Jointed appendages (legs)
In complete metamorphosis, what is the name of the worm-like stage that hatches from the egg?
A) Larva
B) Pupa
C) Nymph
A) Larva
Cnidarians like jellyfish and corals have two different body forms. What are they called?
A) Polyp and Medusa
B) Larva and Adult
C) Sponge and Spicule
A) Polyp and Medusa
How can you tell a roundworm apart from a segmented worm?
A) Roundworms have smooth bodies, while segmented worms have rings
B) Roundworms are always flat like pancakes
C) Roundworms have legs, but segmented worms do not
A) Roundworms have smooth bodies, while segmented worms have rings
Echinoderms, such as sea stars, have an internal skeleton made of hardened plates called an ________.
A) Exoskeleton
B) Endoskeleton
C) Backbone
B) Endoskeleton
Crustaceans, such as crabs and lobsters, belong to a group of arthropods that usually live in water. How do most of them breathe?
A) Through their skin
B) Using lungs
C) Using gills
C) Using gills
In incomplete (gradual) metamorphosis, the young insect looks like a tiny adult without wings. What is this stage called?
A) Pupa
B) Larva
C) Nymph
C) Nymph
Cnidarians use special stinging cells on their tentacles to stun prey. What are these cells called?
A) Pores
B) Nematocysts
C) Flagella
B) Nematocysts
Earthworms are segmented worms (Annelids). What are the tiny hair-like bristles they use to grip the soil?
A) Tentacles
B) Setae
C) Spicules
B) Setae
Which group of mollusks, including clams and oysters, has two shells held together by hinges and strong muscles?
A) Gastropods
B) Cephalopods
C) Bivalves
C) Bivalves
Spiders and scorpions are part of the Chelicerata group. How many walking legs do these animals have?
A) Six legs
B) Eight legs
C) Ten legs
B) Eight legs
During which stage of complete metamorphosis does the insect stay inside a protective case while its body completely changes?
A) Egg
B) Pupa
C) Adult
B) Pupa
Sponges and cnidarians can reproduce asexually through a process where a new organism grows on the side of the parent. What is this called?
A) Fertilization
B) Budding
C) Migration
B) Budding
Unlike simpler worms, segmented worms have a closed circulatory system. What does this mean?
A) Blood moves freely through body cavities
B) Blood stays inside a network of tubes or vessels
C) They do not have any blood or hearts
B) Blood stays inside a network of tubes or vessels
Sea stars and sea urchins belong to the echinoderm group. What kind of body symmetry do adult echinoderms have?
A) Radial symmetry
B) Bilateral symmetry
C) No symmetry
A) Radial symmetry
Unlike insects, which have antennae, which of these groups is known for having no antennae at all?
A) Crustaceans
B) Chelicerates
C) Centipedes
B) Chelicerates
Into how many main sections is an insect's body divided?
A) Two sections
B) Three sections
C) Five sections
B) Three sections