Sponge

Question 1

what is a choanoflagellate?

Answer 1

a collared flagellates both single cell and colony forming eukaryotes found in marine, brackish and freshwater habitats

Question 2

what does a choanoflagellate look like?

Answer 2

it has a head, a collar the mircovilli and a flagella - like a sperm with a skirt on on a stalk attached to the seafloor

Question 3

what do amoeboid cells do?

Answer 3

keep the mesohyl free of bacteria and contaminants

Question 4

defining characteristic of phylum porifera?

Answer 4

microvillar collars surround flagella with units arising from either single cells or syncytia

Question 5

define syncytia

Answer 5

a single cell or cytoplasmic mass containing several nuclei, formed by fusion of cells or by division of nuclei.

Question 6

how many species of sponge?

Answer 6

5- 10,000

Question 7

what dont sponges have?

Answer 7

no nervous system, no muscle, no organs, no symmetry and no basement membranes to support epithelial cells

Question 8

sponges were an evolutionary dead end true or false?

Answer 8

true

Question 9

define spongocoel

Question 10

define spicule

Question 11

define pinacoderm

Answer 11

external cell surface composed of simple epithelial cells. they are contractile and line the outer surface, incurrent canal and the spongocoel when no choanocytes are present

Question 12

define mesohyl

Answer 12

acellular structure containing cells but the matrix is not made up of cells, gelatinous supporting tissue

Question 13

what do choanocytes do?

Answer 13

capture food cells, generate currents that help maintain water current and capture sperm for fertilisation

Question 14

define totipotent cells

Answer 14

develop into more specialised cells

Question 15

what do archaeocytes do?

Answer 15

digest food particles, some give rise to sperm and eggs , play an active role in non-self- recognition reactions when in contact with other sponges

Question 16

spicule size names?

Answer 16

microscleres are tiny and they reinforce the internal surfaces
megacleres and bigger groups - have a structural function,

Question 17

general morphology?

Answer 17

a system of branched canals with choanocytes chambers with neither a mouth nor an anus, pinacoderm on outside, mesohyl in the middle, choanoderm inside

Question 18

three basic levels of sponges

Answer 18

1. asconoid
2. syconoid
3. leuconnoid
   increased complexity 1-3

differ in degree of evagination of the choanocyte layer away from the spongocoel - increases amount of choanoderm enclosed by the sponge

Question 19

whats an Asconoid?

Answer 19

Flagellated Spongocoel
small tube shaped , water enters through pores and go directly to the spongocoel, singe layer of choanocytes
very small in size
Asconoids only in the class Calcera (Leucosolenia)

Question 20

define Syconoid

Answer 20

level 2 sponge, flagellated canals,

Question 21

define Leuconoid

Answer 21

level 3 sponge - Flagellated chamber
most complex of the sponges, increased sponge size
lots of canals in the chambers
most sponges are leuconoid

Question 22

water comes in through the?

Answer 22

ostia

Question 23

define Hexactinellida

Answer 23

deep sea, silica skeleton “glass sponges”, have no choanoderm

Question 24

what are the three classes of Porifera?

Answer 24

Hexactinellida, Calcerea, demospongae

Question 25

define Class Calcerea

Answer 25

all marine, spicules composed of only calcium carbonate.

Question 26

define class Demospongiae

Answer 26

80% of all sponges, nearly all leuconoid. all freshwater sponges are this class. skeletons made of everything ( silica, fibrous and calcium)

Question 27

sponges are unselective particle feeders true or false?

Answer 27

true

Question 28

how many litres can a large sponge filter per day?

Answer 28

1500

Question 29

what does POC stand for?

Answer 29

particulate organic carbon

Question 30

what does DOM stand for?

Answer 30

dissolved organic nutrients

Question 31

define asexual reproduction

Answer 31

offspring arise from a single organism, and inherit the genes of that parent only

Question 32

define sexual reproduction

Answer 32

two haploid cells combine into one diploid cell in a process of fertilisation

Question 33

what are the four types of Asexual reproduction in Sponges?

Answer 33

1. Fragmentation (fish etc)
2. gemmules
3. buddings
4. asexual larvae

Question 34

sexual reproduction in Sponges?

Answer 34

most sponges are hermaphroditic / monoecious (both sexes
- individuals cannot self fertilise as they produce egg and sperm at different times

Question 35

what is spermatogenesis?

Answer 35

sperm follicles form when all the cells of a choanocyte chamber are transformed into spermatogonia or when transformed choanocytes migrate into mesohyl and aggregate there.

Question 36

define smoking sponges?

Answer 36

when mature sponges are in their male phase they release their sperms all at once and it looks like a large smoke show from the sponge.

Question 37

define Oviparity

Answer 37

zygotes develop outside the body - eggs and sperm released. fertilisation and development proceed externally

Question 38

define Viviparity

Answer 38

zygotes develop within body - fertilisation and development proceed in the mesohyl, ciliated larvae released (Occurs in most sponges)

Question 39

what are the two types of development in sexual reproduction?

Answer 39

Oviparity and Viviparity