Chp 33 Part 2

Question 1

What are chitons?

Answer 1

• Oval shaped marine animals encased in an armor of eight dorsal plates

Question 2

What are some characteristics of gastropods? (4)

Answer 2

• most are marine, but many are terrestrial and freshwater species
• Move slowly by a rippling motion of the foot or by cilia
• ## Most have a single, spiraled shell that functions in protection from injury, dehydration, and predationMost gastropods are herbivores, but some species use modified radula to feed on prey

Question 3

What are bivalves?

Answer 3

• aquatic and include many species of clams, oysters, mussels, and scallops
• They have a shell divided into two halves drawn together by adductor muscles

Question 4

What are cephalopods?

Answer 4

Cephalopods are carnivores with beak-like jaws surrounded by tentacles of their modified foot

Question 5

What do cephalopods have? (3)

Answer 5

A closed circulatory system, well-developed sense organs, and a complex brain.

Question 6

What are shelled cephalopods called?

Answer 6

Ammonites

Question 7

What animal group has the largest number of recent extinctions?

Answer 7

Molluscs

Question 8

What are the most threatened molluscs groups?

Answer 8

Freshwater bivalves (pearl mussels)
- Terrestrial gastropods (Pacific Island land snail )

Question 9

What are molluscs threatened by?

Answer 9

• habitat loss
• pollution
• non-native species

Question 10

What are annelids?

Answer 10

coelomates with bodies composed of a series of fused rings

Question 11

What are the 3 traditional clades of the phylum Annelida? (3)

Answer 11

• Polychaeta (polychaetes)

-Oligochaeta (oligochaetes)

• Hirundinea (leeches)

Question 12

What are the more recent 2 major clades of Annelids?

Answer 12

• Errantia
• Sedentaria

Question 13

What are errantians?

Answer 13

Members of the clade Errantia that are mobile, marine organisms that have paddle-like or ridge-like structures called parapodia on each body segment.

Question 14

What are sedentarians?

Answer 14

Organisms that are less mobile than errantians.

• Contains leeches and earthworms

Question 15

What do leeches include?

Answer 15

Predators of invertebrates and parasites that suck blood

• live in fresh water, some are marine or terrestrial

Question 16

What are earthworms?

Answer 16

Organisms that eat thru soil, extracting nutrients as the soil moves thru the alimentary canal

• asexually reproduce via fragmentation

Question 17

What is the most species-rich animal group?

Answer 17

Ecdysozoans

Question 18

What is a cuticle?

Answer 18

A touch coat that covers the ecdysozoans

Question 19

What is ecdysis?

Answer 19

A process in which the cuticle is shedded or molted

Question 20

What are the two largest phyla of Ecdysozoans?

Answer 20

• Nematodes
• Arthropods

Question 21

What are the 3 major lineages of arthropods?

Answer 21

• Chelicerates (sea spiders, horseshoe crabs, scorpions, ticks, mites, and spiders)
• Myriapods (centipedes and millipedes)

-Pancrustaceans (lobsters and other crustaceans, as well as insects and their relatives)

Question 22

What are chelicerae?

Answer 22

Clawlike feeding appendages found in chelicerates

Question 23

What were the earliest chelicerates?

Answer 23

• Eurypterids (water scorpions)

Question 24

What are most modern chelicerates?

Answer 24

Arachnids: spiders, scorpions, ticks, and mites

Question 25

What are book lungs?

Answer 25

Respiratory organs where gas exchange occurs in spiders

Question 26

What does the clade Myriapods include?

Answer 26

- millipedes - centipedes

Question 27

What makes up pancrustaceans?

Answer 27

- insects - crustaceans

Question 28

What consists of crustaceans? (4)

Answer 28

- lobsters - crabs - crayfish - shrimp

Question 29

What are pill bugs?

Answer 29

Well-known group of terrestrial isopods

Question 30

What do planktonic crustaceans include?

Answer 30

Many species of copepods

Question 31

What are barnacles?

Answer 31

A group of mostly sessile crustaceans

Question 32

What is the hexapoda?

Answer 32

Enormous clade that includes insects and their relatives (6-legged)

Question 33

What happens during incomplete metamorphosis?

Answer 33

The young or nymphs resemble adults but are smaller and go through a series of molts until they reach full size

Question 34

What do insects with complete metamorphosis have?

Answer 34

- Has larval stages known by such names as maggot, grub, or caterpillar

Question 35

What is in the clade deuterostomes? (2)

Answer 35

- Echinoderms - Chordates

Question 36

What is included as echinoderms?

Answer 36

stars sea urchins

Question 37

What is included in the chordates?

Answer 37

Vertebrates

Question 38

What are some shared developmental characteristics of Deuterostomes? (2)

Answer 38

- Radial cleavage - Formation of the anus from the blastopore

Question 39

What are the 5 clades of living echinoderms?

Answer 39

- Asteroidea (sea stars and sea daisies) - Ophiuroidea (brittle stars) - Echinoidea (sea urchins and sand dollars) - Crinoidea (sea lilies and feather stars) - Holothuroidea (sea cucumbers)

Question 40

What is a one example of great success of insects?

Answer 40

- Flight; insect wings are an extension of the cuticle