spongES

Question 1

What changes have been observed in ocean conditions

Answer 1

hotter, more jellies

Question 2

How have the changes affected the jellyfish population?

Answer 2

climate change and resulting warmer sea temperatures favor most jellyfish species. -Higher water temperatures both speed jellyfish reproduction and extend the reproductive season.

• Overfishing favors jellyfish because it eliminates their predators (they have very few anyway) and competitors.
• The structures and construction that we have placed in the water, such as piers, marinas, oil platforms, artificial reefs, refuse, rubble, aquaculture pens and structures, etc. provide an abundance of habitats for polyps to settle on

Question 3

Describe the effects changing the jellyfish populations are having on humans and natural ecosystems

Answer 3

Jellyfish blooms disrupt the fishing industry by tearing nets and harming fish. Smaller jellyfish or jellyfish tentacles can enter aquaculture pens and suffocate the fish. Jellyfish sting swimmers, discouraging tourism. They clog cooling water intakes at power plants, causing power reductions or shutdowns. And jellyfish reduce the population of the fish that humans like to eat, by consuming the zooplankton they need and eating their eggs, larvae and juveniles.

Question 4

Animals without tissues?

Answer 4

phylum Porifera

Question 5

Characteristics of a sponge/phylum Porifera

Answer 5

• Simplest animals
• asymmetrical
• first animals
• sac-like body plan
• no tissues, specialized cells only (same as organs)

Question 6

Are phylum profitera (sponge) motile?

Answer 6

No they are sessile; remained fixed in one place during adult life

Question 7

what is the skeleton of a sponge made of?

Answer 7

soft sponge fibers or hard spicules (help ID a sponge)

• calcareous
• silica

Question 8

Look at the anatomy of a sponge

Answer 8

Ostium: where water enters
Spicule: provides structure for the sponge
Osculum: where water exits
Collar Cell: get food and protein for the cell
Porocyte: takes water in
Amebocyte: digests and distributes proteins around the cell

Question 9

how do sponges feed

Answer 9

filter feeders: capture food particles from incoming water

• beating of flagella creates a constant current of water through the sponge
• food items are taken to individual cells by amebocytes, which digest and distribute throughout the sponge

Question 10

how do sponges reproduce asexually

Answer 10

occurs by budding, regeneration, fragmentation, and format on of gemules. (gemules can survive in unfavourable conditions.

Question 11

how do sponges sexually reproduce

Answer 11

reproduction involves the formation of sperm and eggs.. Sperms are broadcast into the water, fertilization is internal and occurs when sponges filter sperm from the current. Fertilized eggs develop onto free swimming larvae.

Question 12

Sponges role to the environment?

Answer 12

• Act as a shelter/home for smaller animals

- Food for molluscs, sea stars and fish

Question 13

how do sponges excretion

Answer 13

release metabolic wastes into the water that flows through their interior

Question 14

respiration, circulation functions

Answer 14

not specialized; occurs by diffusion

Question 15

Cnidarians (Phylum Cnidarian) (jellyfish) characteristics

Answer 15

• radial symmetry

- diplobastic; two layers of cells

Question 16

layers of cells in jellyfish

Answer 16

ectoderm: epidermal cells (protection) and nematocysts
endoderm: secretes digestive enzymes and absorbs nutrients
Mesoglea: (jellylike) contains different cell types, nerve like cells and contractile epidermal cells (movement)

Question 17

nerve tissue in jellyfish?

Answer 17

• nerve net encircles the body

- sensitive to touch and chemicals

Question 18

Respiration and secretio and circulation in jellyfish occur via

Answer 18

• diffusion with water

- circulation; diffusion of nutrients from central cavity to body cells

Question 19

what is cnidocyte

Answer 19

(cnidae=sting thread) specialized cells that contain an organelle called a nematocyst

• harpoon like structure
• contain a barbed thread that is discharged with an explosive force

Question 20

Look at diagram of cnidocyte

Answer 20

lOOk

Question 21

Feeding for jellyfish

Answer 21

• Nematocyst aid in capture of prey
• Captured prey typically moved by tentacles through mouth into gastrovascular cavity, digestion and absortion of nutrients occurs within gastrovascular cavity

Question 22

Body forms of jellyfish

Answer 22

Polyp: sessile with upright tentacles arranged around the mouth
Medusa: free swimming animals with tentacles hanging down around the mouth (contracting bell aids in feeding)
-some cnidarians are polymorphic or go through both polyp and medusa stages in their lifestyles

Question 23

reproductive polyp

Answer 23

-releases male and female medusa (creates genetic diversity)

Question 24

external fertilization

Answer 24

-produce free swimming ciliated larvae (expand into new areas)

Question 25

planula larvae

Answer 25

attaches to a substrate; develops into a hydroid colony.

Question 26

look at obelia life cycle

Answer 26

look

Question 27

what 3 classes are phylum species distributed into?

Answer 27

Hydrozoa (obelia), sessile, primary body form-polyp
Scyphozoa (jellyfish); motile (can move themselves), polymorphic life cycles though medusa stage is dominant
-adult medusa release gametes into water
-zygotes attach to surface; develops into polyps
-polyps reproduce medusa again
-Anthozoa (sea anemones, coral); primarily sessile polyps, more complex tissue structures, includes reef-forming corals (with symbiotic relationship with algae)