glossary

Question 1

what is phylum porifera?

Answer 1

the sponges

Question 2

what is an asconoid?

Answer 2

the simplest form of sponge, usually tube shaped

Question 3

what is a syconoid?

Answer 3

second simplest form of sponge, but the body wall is wiggly.

Question 4

what is a leuconoid?

Answer 4

the most complex structure of the sponges, it has multiple chambers.

Question 5

what are parazoa?

Answer 5

multi cellular animals with very little specialisation of cells.

Question 6

what is a pinacocyte?

Answer 6

a type of flat cell that covers the external surface and incurrent and excurrent canals in sponges.

Question 7

what are porocytes?

Answer 7

tubular cells which make up the pores of sponge, known as ostia.

Question 8

what is a choanocyte?

Answer 8

a flagellated cell with a collar of protoplasm that line the internal chambers of sponges.

Question 9

what are sclerocytes?

Answer 9

these are essential for the excretion of spicules, they are specialised cells which create the mineral structure.

Question 10

what is a gemmule?

Answer 10

an internal bud found in sponges that is involved in asexual reproduction. it is a cluster of embryonic cells.

Question 11

what does monoecious mean?

Answer 11

to have both male and female sexual organs in one individual.

Question 12

what does diploblastic mean?

Answer 12

an animal that has a body wall made up of two layers, sometimes with a non cellular mesoglea between the two layers.

Question 13

what is the ectodermis?

Answer 13

one of the three primary layers in an early embryo

Question 14

what is the endodermis/gastrodermis?

Answer 14

an inner layer of cells that serves as a lining membrane.

Question 15

what is the mesoglea?

Answer 15

a jelly like substance that sits between the endodermis/gastrodermis and the ectodermis/epidermis.

Question 16

what is a polyp?

Answer 16

it is a phase in the life-cycle of the phylum cnidaria, it is a column body with a mouth at the top surrounded by tentacles.

Question 17

what is a medusa?

Answer 17

a medusa is a free swimming sexual form of cnidaria, it typically has an umbrella shaped body and tentacles with stingers.

Question 18

what is alternations of generations?

Answer 18

the alternation between a sexual form and a asexual phase in the life cycle of an organism.

Question 19

what is dimorphism?

Answer 19

the representation of two distinct forms

Question 20

what is polymorphism?

Answer 20

the occurrence of many different forms among the same members of the population.

Question 21

what is a gastrozooid?

Answer 21

an organism with a mouth and digestive organs

Question 22

what is gonozooid?

Answer 22

a term applied to an animal species that practises alternations of generations. its only function is to reproduce (typically)

Question 23

what is meant by dactylozooid?

Answer 23

a polyp like form that does not have a mouth and is heavily armed with nemocytes for protection.

Question 24

what is a gastrovascular cavity?

Answer 24

a body cavity with a highly branched canal system featuring digestive and circulatory functions.

Question 25

what are cnidocytes (nemocytes)?

Answer 25

they are used to catch prey and for protection, they secrete toxins and poisons.

Question 26

what is a nerve net?

Answer 26

a network of cells connected by fusion. in some invertebrates, it is only in the body wall.

Question 27

what is a septa?

Answer 27

a wall separating two cavities.

Question 28

what are hydrozoa?

Answer 28

small predatory animals such as jellyfish and corals. all marine.

Question 29

what are hydroids?

Answer 29

the asexual polyp stage in the life cycle of a hydrozoa . it can also be when the polyp form is dominant over the medusa form.

Question 30

what is a scyphozoa?

Answer 30

the true jellyfish, exclusively marine.

Question 31

what are cubozoa?

Answer 31

commonly known a the cube jelly fish or box jelly fish.

Question 32

what is the class of anthozoa?

Answer 32

the class that includes sea anemones and corals.