Lab 6: invertebrates I

Question 1

what is an animal

Answer 1

living organism that feeds on organic matter, with specialized sense organs, a nervous system, and the ability to respond to stimuli

Question 2

animals form what monophyletic clade

Answer 2

metazoans

Question 3

what is the basal taxon on the animal tree of life

Answer 3

sponges (phylum porifera) - do not form true tissues

Question 4

what is the name of a monophyletic clade that posesses true tissues

Answer 4

eumetazoans

Question 5

what is a tissue

Answer 5

group of cells with a similar structure and work together

Question 6

what is an organ

Answer 6

collection of tissues that form a unit of specialized funciton

Question 7

what is an organ system

Answer 7

group of organs working together to perform a complex function

Question 8

what is an organism

Answer 8

living being with an organized structure, can repsond to stimuli, reproduce, grow, adapt, maintain homeostasis

Question 9

how are differences expressed in eumetazoans (9)

Answer 9

habit (free-living/symbiotic, sedentary/motile, predators/prey)
habitat (aquatic/terrestrial)
symmetry (bilateral/radial)
segementation of body parts
tissue organization
coelom
embryonic development
organs (gut is either a cavity or tube)
organ systems (open/closed circulatory system, nervous system, reproductive system (external/internal, direct/indirect)

Question 10

sponge phylum

Answer 10

phylum porifera

Question 11

how is a sponge’s body organized

Answer 11

around a series of holes and channels to accomodate water flow

Question 12

how does a sponge’s body organization help it survive

Answer 12

allows sponge to use water as a mechanism for nutrients by increasing surface area

Question 13

water flow in a sponge

Answer 13

enters through ostia - flows through many small passageways - exists through osculum

Question 14

how is water current maintained in sponges

Answer 14

choanocytes (flagellated cells) that line the passageways and trap food particles

Question 15

what is the advantage of having a complex system of water channels

Answer 15

gather food, respiratory exchange, removal of waste

Question 16

other cells in sponges (3)

Answer 16

porocytes, amoebocytes, epidermal cells

Question 17

how do sponges protect themselves if they are sessile

Answer 17

colour, produce toxins, regeneration

Question 18

how do sponges reproduce

Answer 18

asexual - budding/fragmentation
sexual - spawning

Question 19

what phylum are cnidarians

Answer 19

phylum cnidaria

Question 20

examples of cnidarians

Answer 20

jellyfish, sea anemones, corals

Question 21

are cnidarians herbivores or canivores

Answer 21

marine carnivores

Question 22

cnidarians symmetry

Answer 22

radial

Question 23

2 body forms in cnidarian life cycle

Answer 23

medusa and polyp

Question 24

how many germ layers do cnidarians have

Answer 24

diploblastic (ecto and endoderm) - epidermis and gastrodermis

Question 25

what are cnidocytes and what are they used for

Answer 25

stinging cells - aid in capturing prey, detecting predators

Question 26

do all colonial cnidarians have the same type of organism in one colony

Answer 26

no! different individuals have different functions

Question 27

how is genetic variation perpetuated in life forms without medusa

Answer 27

gametes are produced by polyp and released into water for external fertilization

Question 28

what are the two subdividions of phylum cnidaria

Answer 28

medusozoans and anthozoans

Question 29

why is phylum cnidaria divided

Answer 29

medusozoans = have medusa stage in life cycle anthozoans = only polyp stage

Question 30

what phylum and clade are flatworms in

Answer 30

phylum platyhelminthes clade lophotrochozoans

Question 31

shape of flatworms

Answer 31

flattened dorso-ventrally

Question 32

how many germ layers do flatworms have

Answer 32

triploblastic (ecto, meso, endoderm)

Question 33

flatworms symmetry

Answer 33

bilateral

Question 34

flatworms and cephalization

Answer 34

tendancy towards cephalization

Question 35

do flatworms have a coelom

Answer 35

no

Question 36

why do endoparasites have such complex life cycles

Answer 36

extreme specialization: direct transmission from parent indirect transmission from host/vector

Question 37

3 free-living flatworms

Answer 37

planarians, trematodes, cestodes

Question 38

do endoparasites have asexual and sexual reproduction

Answer 38

yes

Question 39

what kind of hosts do many endoparasites have

Answer 39

intermediate and final hosts

Question 40

how do endoparasites protect themselves against the digestive system of their host

Answer 40

inhibitor proteins that suppress trypsin activity and protect against digestion

Question 41

difference between protosomes and deuterosomes

Answer 41

P: first opening in embryo develops into the mouth D: first opening in embro develops into anus

Question 42

phylum of molluscs

Answer 42

phylum mollusca

Question 43

what are the diagnostic features of molluscs

Answer 43

shell, foot, radula, mantle, visceral mass

Question 44

four clades of molluscs

Answer 44

polyplacophoa (chitons), gastropoda (snails, slugs), bivalvia (clams, oysters), cephalopoda (squid, octopus)

Question 45

characteristics of polyplacophora

Answer 45

shell with 8 overlapping plates, broad foot, radula to scrape algae off rock

Question 46

characteristics of gastropoda

Answer 46

single spiral shell, head with tentacles

Question 47

characteristics of bivalvia

Answer 47

2 part-hinged shell large, muscular foot filter feed by siphoning water

Question 48

characteristics of cephalopoda

Answer 48

reduced internal shell tentacles with suckers move by jet propulsion

Question 49

are molluscs coelomate and segmented

Answer 49

no

Question 50

what is visceral mass

Answer 50

contains internal organs, gills, anus - opens into mantle cavity

Question 51

what is a mantle

Answer 51

forms shell

Question 52

what is the radula

Answer 52

scraping tool

Question 53

phylum of segmented worms

Answer 53

phylum annelida

Question 54

annelida habitat

Answer 54

water and land

Question 55

what is on the surface of a preserved worm

Answer 55

prostomium, peristomium, pygidium

Question 56

where is the male gonospore on a worm

Answer 56

segment 15

Question 57

where is the female gonospore on a worm

Answer 57

segment 14

Question 58

where are the openings of the seminal receptacles on a worm

Answer 58

btwn segments 9/10 and 10/11

Question 59

how many pairs of chatae and where are they found

Answer 59

4 pairs, 2 ventro-lateral and two ventral

Question 60

where is the brain located in a worm

Answer 60

dorsal to buccal cavity

Question 61

what is the brain made of in a worm

Answer 61

2 small ganglia with nerves connecting to ganglia on ventral surface (nerve ring)

Question 62

where does the nerve cord run in a worm

Answer 62

ventrally through entire length of animal with ganglia in each segment (segmental nerves arise from the ganglia)

Question 63

what is above and attached to the nerve cord

Answer 63

ventral blood vessel

Question 64

what are the two main annelid clades

Answer 64

errantia and sendentaria

Question 65

define segmentation

Answer 65

division of one organism into similar sections

Question 66

which systems are segmented in worms

Answer 66

nervous, digestive, circulatory

Question 67

what is the advantage to segmentation

Answer 67

flexibility, mobility, ablility to sustain injury without incapacitation

Question 68

what allows earthworms to ingest earth and extract minerals

Answer 68

muscular pharynx, gizzard, long intestine

Question 69

how does sexual reproduction take place if earthworms are hermaphrodite

Answer 69

2 worms exchange sperm then they internally fertilize the egg

Question 70

adaptations of a leech

Answer 70

suckers, salivary glands secreting anti-coagulant/anesthetic compound, expandable body