Phylum Cnidaria (J.3)

Question 1

Epidermis (ectoderm)

Answer 1

Thin protective outside layer of skin cells

Question 2

Gastrodermis (endoderm)

Answer 2

Inner layer, mainly for digestion

Question 3

Mesoglea

Answer 3

Gel-like layer that is between the ectoderm and endoderm of members of Phylum Cnidaria

Question 4

Cnidocytes

Answer 4

Specialized cells which contain nematocysts which are detrimental to prey capture and predator defence

Question 5

Nematocysts (cnidoblast)

Answer 5

Stinging cell, equipped with barbs which can snare prey (like a harpoon)

Question 6

Gastrovascular cavity

Answer 6

Body cavity where digestive enzymes are secreted and nutrients are absorbed

Question 7

Nerve net

Answer 7

Arrangement of nerve cells of members of Phylum Cnidaria. Develop in the mesoglea and coordinate basic movements (like those of the feeding tentacles)

Question 8

Polyp/ Medusa

Answer 8

Body forms
Polyp - Sessile, tube shaped body form
Medusa - Motile, umbrella shaped body form

Question 9

Tentacles

Answer 9

Elongate flexible structure found on the head or around the mouth of organisms with “devices” for attachment

Question 10

Planula

Answer 10

Free-swimming/ crawling larvae common in many organisms under Phylum Cnidaria

Question 11

Basal disk

Answer 11

Flattened substance by which polyps attach themselves