Chapter 2 Sections 1,2,3,& 4

Question 1

What is the simplest invertebrate?

Answer 1

Sponges

Question 2

What is a more complex invertebrate

Answer 2

Cnidarians

Question 3

What is complete metamorphosis?

Answer 3

There are FOUR main stages: egg, larva, pupa, and adult. An example would be: butterflies, beetles, flies, bees, wasps, and ants.

Question 4

What is incomplete metamorphosis?

Answer 4

There are THREE main stages: egg, nymph, and adult. Examples are: grasshoppers and cockroaches

Question 5

Describe an open and closed circulatory system.

Answer 5

Open: the circulatory fluid is not contained entirely with vessels. Example: most mollusks have an open circulatory system.

Closed: the heart circulates blood through a network of blood vessels that formed a closed loop. Example: squid and octopuses have a closed circulatory system.

Question 6

Compare an endoskeleton to an exoskeleton.

Answer 6

An endoskeleton is an internal skeleton made of bones or cartilage. An exoskeleton a hard, external, supporting structure. Endoskeleton and exoskeleton are like a backbone for invertebrates. The endoskeleton can be hard and bumpy or stiff and flexible. Sometimes the endoskeleton have spines; they can be short and bumpy. The skin covers the endoskeleton. Example: sea urchins, Echinoderms, and starfish.

Question 7

Compare radial symmetry and bilateral symmetry. What invertebrate changes symmetry from larva to adult?

Answer 7

Radial-it’s body is organized around the center, like spokes on a wheel. Example: sea star

Bilateral- 2 sides of its body mirror itself. Example: ant.

A sea urchin is an invertebrate that goes through stages of bilateral symmetry and radial symmetry.

Question 8

Characteristics of Arthropods.

Answer 8

A segmented body with specialized parts, jointed limbs, an exoskeleton, bristles, and a well-developed nervous system.

Question 9

Characteristics of insects

Answer 9

Six legs, compound eyes,mandibles, one set of antennae, head, thorax, and abdomen.

Question 10

Characteristics of crustaceans

Answer 10

Gills for breathing in water, mandibles for eating, two antennae, and two compound eyes.

Question 11

Characteristics of arachnids

Answer 11

Chelicerae, no antennae, simple eyes, and a cephalothorax

Question 12

Characteristics of centipedes

Answer 12

Mandibles, dozens of legs, and are segmented

Question 13

What are the body forms of Cnidarians? What characteristics do all Cnidarians share?

Answer 13

Body forms of Cnidarians: 1. Medusa 2. Polyp
Characteristics: move faster than sponges, if broken into smaller pieces they form new Cnidarians, and they all have stinging cells.

Question 14

Compare a compound eye to a simple eye

Answer 14

A compound eye: an eye composed of many light detectors.
A simple eye: an eye that can detect light, but can not see an image.
They both can still detect light. Example: insect- compound eye arachnid- simple eye

Question 15

Describe neurons and ganglions

Answer 15

Neurons: a special tissue that makes fibers

Ganglion a mass of nerve cells

Question 16

What are the classes of mollusks? Describe each

Answer 16

1. Gastropods- slugs and snails.
2. Bivalves- clams and other shellfish that have two shells.
3. Cephalopods- squids and octopuses.

Question 17

Give an example of an annelid worm

Answer 17

Example: earthworm

Question 18

Give examples of flatworms

Answer 18

1. Marine worms
2. Flukes
3. Tapeworms
4. Planarians

Question 19

Define parasite and give an example

Answer 19

Parasite: an organism that invades and feeds on the body of another living organism called a host. Example: flukes

Question 20

Sponges are not plants. Why? Describe

Answer 20

Sponges aren’t plants because they can’t make there own food that’s why they are classified as animals. They are asymmetrical, have no tissues, gut or neurons.

Question 21

A body cavity that contains the internal organ

Answer 21

Coelom

Question 22

The digestive tract

Answer 22

Gut

Question 23

A mass of nerve cells; connected by nerve cord; controlled by the brain.

Answer 23

Ganglion

Question 24

An animal that does not have a backbone

Answer 24

Invertebrate

Question 25

A circulatory system in which the circulatory fluid is not contained entirely with vessels.

Answer 25

Open circulatory system

Question 26

A circulatory system in which the heart circulates blood through a network of blood vessels that form a closed loop

Answer 26

Closed circulatory system

Question 27

Any part of a larger structure such as the body of an organism, that is set off by natural or arbitrary boundaries

Answer 27

Segment

Question 28

A hard, external, supporting structure

Answer 28

Exoskeleton

Question 29

An eye composed of many light detectors

Answer 29

Compound eye

Question 30

A feeler that is on the head of an invertebrate, such as a crustacean or an insect, that senses touch, taste, or smell.

Answer 30

Antennae

Question 31

A phase in the life cycle of many animals during which a rapid change from the immune form of an organism to the adult form takes place.

Answer 31

Metamorphosis

Question 32

An internal skeleton made of bone or cartilage

Answer 32

Endoskeleton

Question 33

A system of canals filled with watery fluid that circulates throughout the body of an echinoderm

Answer 33

Water vascular system