Protostomes- Chapter 34

Question 1

no body cavity

Answer 1

acoelomate

Question 2

body cavity between mesoderm and endoderm (called the pseudocoel)

Answer 2

pseudocoelomates

Question 3

body cavity entirely within the mesoderm (called the coelom

Answer 3

coelomates

Question 4

What does a coelomate body design allow for?

Answer 4

(1) repositions bod fluid
(2) allows complex tissues/organs to develop
(3) allows for a larger body size

Question 5

a zygote divides to form a ________, a hollow ball of cells

Answer 5

blastula

Question 6

blastula indents to form a two-layer-thick ball with a _____________, which is an opening to the digestive system

Answer 6

blastopore

Question 7

_______________ develop the mouth first from the blatopore. If an anus develops, it comes from another region of the embryo

Answer 7

Protostomes

Question 8

What is the cleavage pattern of the embryonic cells in Protostomes?

Answer 8

spiral cleavage, cells “move” as they divide, happens to the subgroup Spiralia

Question 9

What is the developmental fate of Protostome cells?

Answer 9

determinate development, embryonic cells will form specific body regions, remove one and development ceases

Question 10

How does the coelom originate in Protostomes?

Answer 10

it forms simple and directly from splitting the mesoderm

Question 11

What advantages does segmentation allow for?

Answer 11

(1) allows redundant organ systems in adults (annelids and arthropods)
(2) allows for more efficient and flexible movement because each segment can move independently

Question 12

grow by adding mass to an existing body, obvious spiral cleavage

Answer 12

Spiralians

Question 13

wide variety of sizes and body forms, live in many different environments, include snails, slugs, clams, octopuses

Answer 13

Mollusks

Question 14

most groups have remained in the oceans, many are delicious, pearls are produced in oysters, can be pests

Answer 14

Mollusks

Question 15

What is the Mollusk body plan?

Answer 15

bilaterally symmetrical, except for cephalopods, all mollusks have an open circulatory system (organs are bathed in blood and lymph), a muscular foot is adapted for locomotion, attachment, and food capture

Question 16

epidermis that covers the dorsal side of the body, forms a cavity which houses the respiratory organs and the openings of excretory, reproductive, and digestive organs, these organs together form the visceral mass

Answer 16

mantle

Question 17

What is the purpose of the shell?

Answer 17

CaCO3 rich shell, used for protection, some species have internalized or reduced shells

Question 18

most mollusks have a rasping tongue-like organ called the __________, used originally for scrapping and crushing, now modified into many different structures (sharp beak, drill, poison dart)

Answer 18

radula

Question 19

How do mollusks reproduce?

Answer 19

distinct male and female individuals, most engage in external fertilization, in marine mollusks embryos develop through spiral cleavage

Question 20

free swimming larval stage of mollusks

Answer 20

trochophores

Question 21

second larval stage of mollusks, only in bivalves and gastropods

Answer 21

veliger

Question 22

What are the 3 classes of Mollusks that we need to know?

Answer 22

(1) Polyplacophora
(2) Gastropoda
(3) Bivalvia
(4) Cephalopoda

Question 23

marine mollusk, oval bodies with eight overlapping dorsal calcareous plates, most are grazing herbivores

Answer 23

Chitons (Polyplacophora)

Question 24

primarily marine, some have invaded land, pairs of tentacles with eyes at the ends, during embryological development the undergo torsion (mantle cavity and anus are moved from the posterior to the front) and coiling (spiral winding of the shell)

Answer 24

Snails and Slugs (Gastropoda)

Question 25

have two lateral (right and left) shells (valves) hinged together dorsally, most are sessile filter-feeders, water circulation is mediated by siphons and rhythmic beating of cilia on gills

Answer 25

clams, scallops, mussels, oysters (Bivalvia)

Question 26

active marine predators, have a foot with a series of arms equipped with suction cups, (squids have 10, octopuses have 8, nautiluses have 80-90), have highly developed nervous systems, complex behavior and intelligence

Answer 26

Cephalopoda

Question 27

many Cephalopods have an ____ sac and are capable of expelling ink to confuse predators, many can change color using pouches of pigment called chromatophores

Answer 27

ink

Question 28

worms that always exhibit segmentation, building of body from repeated units, allows for specialization of each unit

Answer 28

Annelida

Question 29

Annelida consist of a series of ring like segments that are divided internally by _______, the front segment contain specialized sensory organs, a ventral nerve cord connect the ganglia in each segment with each other and the _______

Answer 29

septa | brain

Question 30

Annelids move using their ________ as a skeleton, most have a closed circulatory system (blood vessels), exchange O2 and CO2 through their body surfaces, the excretory system repeats at each segment

Answer 30

coelom

Question 31

What are the 2 classes of Annelids?

Answer 31

(1) Polychaeta | (2) Clitellata

Question 32

mostly marine worms, have a differentiated head, have paired _________ on most segments, used in swimming, burrowing, and crawling, sexes are usually separate and many live in tubes

Answer 32

Parapodia

Question 33

includes ___________ mostly terrestrial, live underground and eat their way through soil, consist of 100-175 segments with a mouth on the first and an anus on the last, lack eyes and head, move through soil using __________ (little chitinous bristles that anchor soil, no parapodia)

Answer 33

Earthworms (part of Clitella) | chaetae

Question 34

burrowing and soil consuming, hermaphroditic, _______ secretes mucus that holds the worms together during copulation, also secretes a mucus cocoon in which the fertilized egg develops

Answer 34

clitellum

Question 35

occur mostly in freshwater, usually flattened dorsoventrally, cross-fertilization is obligatory, have no chaetae, medicinal leech secretes an anticoagulant

Answer 35

Leeches (part of Clitellata)

Question 36

increase in size by molting their external skeletons

Answer 36

Ecdysozoans

Question 37

most successful animals, about 1 million species (2/3 of all species, about 80% are insects), affect all aspects of human life

Answer 37

Phylum Arthropoda

Question 38

jointed appendages, have an exoskeleton made of chitin and protein (limit body size and protection), segmented body fused into tagmata (head, thorax, abdomen)

Answer 38

arthropod body plan

Question 39

arthropods have a ____ circulatory system, and ___________ eyes composed of independent visual units

Answer 39

open | compound eyes

Question 40

some arthropods have simple eyes or ______ which have single lenses and distinguish light from dark

Answer 40

ocelli

Question 41

arthropods periodically undergo ______ or molting which is the shedding of the outer cuticule layer of exoskeleton

Answer 41

ecdysis

Question 42

What are the 4 major classes of arthropods?

Answer 42

(1) Chelicerata (2) Myripodia (3) Crustacea (4) Hexapoda

Question 43

includes spiders, scorpions, horseshoe crabs, ticks and mites

Answer 43

class chelicerata

Question 44

Chelicerata have bodies that are divided into ___ main tagmata

Answer 44

two

Question 45

anterior appendages, often function as fangs or pincers

Answer 45

chelicerae

Question 46

posterior to chelicerae, resemble legs, used as copulatory organs, pincers, or sensors

Answer 46

pedipalps

Question 47

order ___________ includes 35,000 species of spiders, catch prey in silk webs forced out of spinnerets, some hunt prey, all spiders have ________________ leading through their chelicerae

Answer 47

araneae | poison glands

Question 48

order _______ includes mites and ticks, large, diverse order, fused tagmata, ticks are larger than mites and are blood eating _____________'s

Answer 48

acari | parasites

Question 49

primarily aquatic organisms, include crabs, shrimps, lobsters, and barnacles

Answer 49

class crustacea

Question 50

crustacea have three tagmata, but the front two may fuse, they also have __ pair of antennae, __ pairs of appendages and various pairs of legs, most appendages are ________ which means they branch into two parts

Answer 50

2 3 biramous

Question 51

evolved from a pair of limbs that took on a chewing function

Answer 51

mandibles

Question 52

the majority of crustacea develop through a _________ stage

Answer 52

nauplius

Question 53

order that includes shrimp, lobsters, crabs, and crayfish, have ten feet, exoskeleton enforced by calcium carbonate, appendages aid in swimming

Answer 53

decapoda

Question 54

order that includes barnacles and crustaceans that are sessile as adults, have free swimming larvae, hermaphroditic, some have stalks

Answer 54

cirripedia

Question 55

class that includes insects, largest group of animals with more than half of all named species, primarily terrestrial

Answer 55

class hexapoda

Question 56

For each human, there are ______ insects alive. That means there are 1 billion billion insects

Answer 56

200

Question 57

What are the 3 regions of hexapoda?

Answer 57

(1) head (2) thorax (3) abdomen

Question 58

includes a pair of antennae, modified mouthparts, compound eyes

Answer 58

head

Question 59

has three pairs of legs, may have one or two pairs of wings

Answer 59

thorax

Question 60

includes of the major organs in the body

Answer 60

abdomen

Question 61

hexapods have a ______ digestive tract, as digestion takes place in the ________, excretion takes place in the __________, and the _______ permeates all tissues

Answer 61

coiled stomach Malpighian tubules tracheae

Question 62

as seen in grasshoppers, immature stage is similar to the adults

Answer 62

simple metamorphosis

Question 63

as seen in butterflies, immature larva are wormlike, a resting stage (pupa or chrysalis) precedes the final molt into adult form

Answer 63

complete metamorphosis

Question 64

part of myriapoda, one leg pain on each segment, are all carnivores, eat insects, may be poisonous

Answer 64

centipedes

Question 65

part of myripoda, two legs on some or all segments, are largely herbivores

Answer 65

millipedes