LAB 1

Question 1

what does porifera mean?

Answer 1

derived from latin porus = pore and ferre = to bear

Question 2

do sponges have true tissues?

Answer 2

sponges are metazoans with no or perhaps simple tissues and specialised cells

Question 3

what are the 3 main sponges body forms?

Answer 3

asconoid, syconoid, and leuconoid

Question 4

what type of symmetry do sponges have?

Answer 4

asymmetry (or superfically radially symmetrical)

Question 5

Are porifera cells totipotent?

Answer 5

yes

Question 6

sponges have choanocytes true or false?

Answer 6

true

Question 7

what is sponges main habitats?

Answer 7

mostly marine (only 2% are freshwater)

Question 8

what type of feeding do sponges have?

Answer 8

filter feeding

Question 9

where does an encrusting sponge grow?

Answer 9

in fast water as encrusting sponges hold togetehr better

Question 10

where does an errect sponge grow?

Answer 10

in slow water. an errect sponge is bigger and used to maximize surface area

Question 11

how might plasticity of the sponge form maximise filter feeding opportunities in various marine habitats?

Answer 11

an encrusting sponge is found in fast currents so has a simple shape and no branching whereas an erect sponge found in slower currents so grows up higher to get more food and is branched and flattened to maximise body surface area.

Question 12

what are the specialised cell types in sponges

Answer 12

pinacoctes, porocytes, basospinacocytes, myocytes, archaeocytes, sclerocytes and choanocytes

Question 13

what is another name for a choanocyte?

Answer 13

collar cell

Question 14

what do choanocytes do?

Answer 14

act as a pump to bring water into the sponge

Question 15

what is choanocyte made up of

Answer 15

20 to 55 cytoplasmic microvilli connected to each other by mucous strands (- flagellated)

Question 16

do choanocytes beat together or independently

Answer 16

independlty

Question 17

what layer do choanocytes form?

Answer 17

choanoderm

Question 18

how do choanocytes generate a current?

Answer 18

generates water currents by flagellar beating

Question 19

how many sponge classes are there?

Answer 19

4

Question 20

what are the sponge classes?

Answer 20

Homoscleromorpha, Calcarea, demospongiae, Hexactinellida

Question 21

what is the largest sponge class?

Answer 21

class Demospongiae

Question 22

how do sponges reproduce?

Answer 22

by asexual budding (gemmules), regeneration of broken pieces and/or sexual reproduction (hermaphroditic)

Question 23

what are the porifera larvae?

Answer 23

ciliated mouth-less larvae (parenchymella)

Question 24

what is the sponge supported by?

Answer 24

two skeletal elements (collagen - organic and spicules - inorganic). the organic content is known as spongin.

Question 25

what can sponge spicules be made of?

Answer 25

silica or calcium carbonate (cant see through)

Question 26

what does cnidaria stand for

Answer 26

greek cnidos = stinging nette

Question 27

what classes are in cnidaria

Answer 27

anthozoa (corals and sea anemones), hydrozoa (hydroids), cubozoa (box jellyfish) and scyphozoa (true jellyfish)

Question 28

what are the main features of cnidaria?

Answer 28

diploblastic, mesoglea separating ectoderm and endoderm, radial(biradia) symmetry, nerve net, closed digestive system, no true body cavity, excretory or circulatory system

Question 29

cnidarians have cnidocytes true or false

Answer 29

true

Question 30

what are cnidocytes

Answer 30

stinging cells

Question 31

apart from cnidae what can cnidaria also have?

Answer 31

spirocysts - non-stinging cells that release sticky tubules of glycoproteins that stick to prey and help for tubes in ceriantharians

Question 32

what are cnidocytes used for

Answer 32

gathering food or defense

Question 33

what are cnidocytes produced in

Answer 33

cnidoblasts

Question 34

what are the 3 tyoes of cnidocytes

Answer 34

nematocystes, spirocysts and ptychocysts

Question 35

what supporting structures does a sea anemone have?

Answer 35

a hydrostatic skeleton produced by pressuring the coelenteron or gastrovascular cavity with seawater.

Question 36

what is the siphonoglyph

Answer 36

a ciliated groove running through the pharynx of the sea anemone that moves water into the gastrovascular cavity (critical in maintaining hydrostatic pressure)

Question 37

what is the dominant stage of lifecycle for scyphozoans

Answer 37

medusa phase

Question 38

what is the dominant phase of lifecycle for hydrozoans

Answer 38

poly phase

Question 39

what type of larvae do hydrozoans have

Answer 39

planula larvae

Question 40

what type of feeding do cnidarians do

Answer 40

suspension, predatory and many symbiotic with zooxnthellae algae

Question 41

what are ctenophores

Answer 41

comb jellies

Question 42

what are the defining characteristics of ctenophora

Answer 42

plates of fused cilia arranged in rows and adhesive prey capturing cells - colloblasts

Question 43

main features of ctenophores

Answer 43

diploblastic, cellular mesenchyme between two layers, mainly water, radial symmetry, no body cavity, nerve net, transparent, no skeleton excretory or respiratory system and bioluminescent

Question 44

how do colloblasts capture prey

Answer 44

sticky retractile tentacle that when discharged sticks to prey

Question 45

how to ctenophores reproduce

Answer 45

can regenerate lost or damaged body parts and are hermaphrodites with a cydippid larval stage