lecture 14

Question 1

what is lophotrochozoa

Answer 1

smaller clade of spiralia

Question 2

what larva do most lophotrochozoa taxa have?

Answer 2

lophophore or trochohore larva

Question 3

what is mollusca a member of

Answer 3

lophotrochozoa

Question 4

what larva is present in many mollusca

Answer 4

trochophore larva

Question 5

what is trochophore larva
what type of organs

Answer 5

a type of primary larva with apical organ

Question 6

what is the second most species rich invertebrate [hylum

Answer 6

mulluscah

Question 7

ow many described species of mollusca

Answer 7

73,000

Question 8

what is cool about size rannge of mollusca

Answer 8

they have the greatest size range of any phylum of invertebrates

Question 9

general features of mollusca coelom

Answer 9

small eucoelom and large open haemocoelic circulatory system

Question 10

haemolymph

Answer 10

circulatory fluid, bathes some organs dirrectly

Question 11

do mollusca have heart?

Answer 11

they have chambered heart

Question 12

how does the euceolum arise in mollusca

Answer 12

via schizocoely but is greatly reduced

Question 13

what are the functions of the haemocoel

Answer 13

it is extensive, it functions as circulatory system and a hydrostatic skeleton

Question 14

what are 8 common features in mollusca

Answer 14

1. small eucoelom and large open haemocoelic circ system
2. chambered heart
3. have mantle
4. calcareous shell or and small sclerites
5. foot
6. radula
7. gut w large digestive glands
8. gills called ctenidia
9. excretory system including metanephridia

Question 15

metanephridia

Answer 15

typical in large animals
filtration occurs in the structure separate frp, resorption and transport

Question 16

what are two clades of mollusca

Answer 16

aculifera and conchifera

Question 17

clade aculifera

Answer 17

-not covered by large shells
-incorporate calcareaous sclerites into mantle.

Question 18

clade conchifera

Answer 18

most of body covered by one or two large shells

Question 19

what is the clade some aculifera are in?

Answer 19

aplacophora

Question 20

what molluscs groups have solid calcareous shell plates

Answer 20

every group except aplacophorans

Question 21

what produces shell

Answer 21

shell glands in mantle

Question 22

the three layers of the shell

Answer 22

periostracum layer
prismatic layer
nacreous layer

Question 23

periostractum

Answer 23

tough proteinacrous layer

Question 24

prismatic layer

Answer 24

chalky calcareous layer, thickest layer of shell

Question 25

nacreous layer

Answer 25

shiny and smooth inner layer
the mother of pearl

Question 26

how do pearls form

Answer 26

when irritant gets into mantle

Question 27

ctenidia

Answer 27

multi leaved gills

Question 28

what is the function of ctenidia

Answer 28

gas exchange

Question 29

what type of gas exchange happens in ctendium

Answer 29

counter current exchange

Question 30

morphology of ctenidium

Answer 30

long flattened central axis with two haemolymph vessels. along with alternately arranged ciliated lamellae

Question 31

sense organs of molluscs

Answer 31

eyes
statocyst
tentacles

Question 32

function of eyes

Answer 32

range from ligth detectors to image forming

Question 33

statocyst function

Answer 33

gravity detecting organ

Question 34

tentacles function molluscs

Answer 34

touch and chemoreception, may bear eyes in gastropoda

Question 35

sexes in mollusca

Answer 35

mostly seperate sex, hermaphroditism is common

Question 36

fertilization in molluscs

Answer 36

mostly external

Question 37

development in molluscs

Answer 37

mostly indirect with trochophore larva