invertebrates

Question 1

What are the 6 characteristics of animal evolution

Answer 1

1. Multicellular eukaryotes
2. Heterotrophic by ingestion or absorption
3. Lack cell wall
4. Produce gametes by meiosis
5. Capable of movement at some stage in their life cycle
6. Descended from single common ancestor

Question 2

What are 4 characteristics of the phylogenetic tree of animals?

Answer 2

1. Presence or absence of segmentation
2. Body symmetry
3. Germ layers
4. Molecular data

Question 3

What are the 3 types of symmetry?

Answer 3

1. Asymmetry: No particular body shape
2. Radial symmetry: Two identical halves
3. Bilateral symmetry: Definite right and left halves (most animals)

Question 4

What give rise to organs and organ systems

Answer 4

germ layers

Question 5

What is it called when embryos have only two tissue layers (ectoderm and endoderm) and lack specialized organs?

Answer 5

diploblastic

Question 6

What is it called when embryos have 3 tissue layers (ectoderm, mesoderm, and endoderm) and have specialized organs?

Answer 6

triploblastic

Question 7

In triploblasts what are coelomate animals in which first embryonic opening (blastopore) is associated with the mouth?

Answer 7

protostomes

Question 8

In triploblasts, what are coelomate animals in which first embryonic opening (blastopore) is associated with the anus?

Answer 8

Deuterostomes

Question 9

Most invertebrates are __________; all vertebrates are ___________.

Answer 9

protostomes; deuterostomes

Question 10

What invertebrate
-Oldest lineages of animals; resemble colonial protozoans
-Reproduce sexually or asexually
-Cellular level of organization, lack tissue, asymmetrical
-Filter feeders

Answer 10

sponges

Question 11

What happens if cells of a sponge are mechanically separated?

Answer 11

If cells of a sponge are mechanically separated, they will spontaneously reassemble into a complete and functioning sponge

Question 12

What invertebrate
-diploblastic
-radially symmetric
-Solitary, most free-swimming
-aquatic environments; Warm waters
-Body composed of mesoglea: transparent, jellylike substance located between the endoderm and ectoderm
-Most lack stinging cells; capture prey using sticky adhesive cells called colloblasts
-Some bioluminescent

Answer 12

Comb jellies (ctenophores)

Question 13

What invertebrate
-Most found in mainly shallow coastal waters
-Specialized stinging cells cnidocytes
-Each has nematocyst: capsule that contains threadlike fiber, release of which aids in capture of prey
-Two tissue layers: outer epidermis and inner gastrodermis
-A jellylike mesoglea separates the two tissue layers
-Inner layer aids in digestion and serves as a supportive hydrostatic skeleton: fluid filled body compartment that provides support for muscle contraction

Answer 13

cnidarians

Question 14

What cnidarian body form is directed upward with small, abnormal growth arising from the epithelia lining?

Answer 14

polyp

Question 15

What cnidarian body form is a bell-shaped body form that is directed downwards and contains much mesoglea

Answer 15

medusa

Question 16

What invertebrate group
1. Lophotrozoa (lophophoran & trochozoan)
2. Platyzoa
-Bilateral symmetry during at least one stage of development
-Protostome animals
-Adults achieve organ level of organization

Answer 16

spiralians

Question 17

what spiralian invertebrate
-Bilateral symmetry at some point in their life
-Feeding apparatus lophopore
-Three germ layers as embryos
-Aquatic
-Protostomes
-Bryozoans, phoronids, and brachiopods

Answer 17

Lophotrochozoan

Question 18

What spiralian invertebrate
-Mollusks and annelids
-Protostomes
-Share patterns of development in early embryonic stages.
-Trochophore larva: larva with two bands of cilia around the middle that are used for swimming and for gathering food, and at the “top” is a cluster of longer flagellae

Answer 18

Trochozoans

Question 19

What trochozoan invertebrate
-Share a three-part body plan consisting of visceral mass, mantle, & foot
-Reduced cephalization: evolutionary trend toward concentrating nervous tissue, the mouth, and sense organs toward the front end of an anima
-May posses hard outer shell
-Nervous system consist of several ganglia connected by nerve cords
-Open circulatory system: “blood” (actually hemolyph) suffuses body cavities
-Clams, snails, squids

Answer 19

Mollusca

Question 20

What trochozoan invertebrate
-Exhibit segmentation: repetition of body units
-Well developed coelom; acts as a hydrostatic skeleton
-Closed circulatory system
-Setae: bristles protrude from body wall that can anchor worm & help it move
-Many hermaphroditic: possessing both male and female reproductive organs, structures, or tissue
-Mate with any other of the same species
-Earthworms, marine worms, leeches

Answer 20

annelids

Question 21

What spiralian invertebrate
-Second major group
-Bilateral symmetry
-No circulatory system
-No respiratory system
-Flatworms and rotifers

Answer 21

platyzoans

Question 22

What platyzoan invertebrate
-Extremely flat body
-Sac body plan with only one opening; the mouth
-Incomplete digestive tract
-No body cavity
-Instead mesoderm fills space between organs

Answer 22

flatworms

Question 23

What platyzoan invertebrate
-Freshwater lakes, streams, ponds
-Feed on small living or dead organism
-Hermaphroditic
-Muscles & ladder-type nervous system with paired ganglia serving as the brain
-Ganglia: bundle of neuron cell bodies
-Take in food through extended pharynx, sucks into gastrovascular cavity, which branches throughout body!

Answer 23

free-living flatworms

Question 24

what platyzoan invertebrate
-Common parasites of vertebrate animals
-Protective tegument: specialized body covering resistant to digestive juices
-Lost cephalization; replaced by anterior end with hooks or suckers
-Nerves system not well developed
-Well developed reproductive system; ensures transmission to new host
-Flukes and tapeworms

Answer 24

parasitic flatworms

Question 25

what invertebrate group
-Periodically shed their outer covering,
-Nonsegmented body plan
-Contain an exoskeleton
-Undergo metamorphosis: Change in shape and form that some animals undergo during development.
-Contain largest number of species

Answer 25

ecdysozoans

Question 26

What ecdysozoans invertebrate
-Smooth unsegmented outside body wall
-Prevalent in almost all environments
-Internal organs in pseudocoelom: body cavity incompletely lined by mesoderm
-Mesoderm occurs inside body wall not around digestive cavity (gut)
-Tube within a tube body plan
-Free-living & parasites

Answer 26

roundworms

Question 27

what ecdysozoan invertebrate group
-Phylum contains the greatest diversity of animal species
1. Exoskeleton: protective external skeleton
2. Segmentation: jointed appendages; clear body regions & high degree of cephalization
3. Well-developed nervous system: Brain & nervous cord
4. Variety of respiratory systems: gills or lungs
5. Life cycle that includes metamorphosis
-Crustaceans, insects, & chelicerates

Answer 27

arthropods

Question 28

what ecdysozoan arthropod invertebrate
-Head bears compound eyes, antennae, antennules, & mouthparts
-Open circulatory system
-Respiration by gills
-Ventral solid nerve cord
-Crayfish, lobsters, shrimps, copepods, krill, & barnacles

Answer 28

crustaceans

Question 29

what ecdysozoan arthropod invertebrate
-Butterflies, grasshoppers, bees, ants, beetles, many more!
-Adapted for life on land; some secondarily invaded aquatic habitats
-Major Body Plan: head, thorax, abdomen
-Remarkable behavioral adaptations!!

Answer 29

insects

Question 30

what invertebrate group
-Echinodermata and Chordata
-Molecular data shows we are closely related
-Morphological data indicates deuterostome pattern of development

Answer 30

invertebrate deuterostomes

Question 31

what invertebrate deuterostome invertebrate
-Gas exchange occurs through skin gills and tube feet
-Larvae are free-swimming and bilaterally symmetrical
-Water vascular system: series of canals take water to tube feet of an echinoderm, allowing them to expand
-Symmetry is radial in the adult
-Usually with parts in fives or multiples of five
-Sea stars, sea urchins, & sea cucumbers

Answer 31

echinoderms