Zooplankton Flashcards

1
Q

What are meroplankton and what are the advantages?

A

Meroplankton are species that have part of their lifecycle in the planktonic stage.

Approx. 80% benthic species have a larval stage. Some stay in the planktonic stages for weeks or months depending in advantageous conditions of the species.

Benefits of small planktonic stage – develop to sexual maturity faster, drift further from colonies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are some of the adaptations in the blue crab larva?

A

See through, can’t be seen.

Star shape to stop settling.

In early larval stages (top right) large spines stops predation from smaller predators.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are some of the adaptations in larval fish?

A

Yolk sac

Transparancy

Fish eggs have lipids and oils to aid buoyancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two larval stages of a crab?

A

Megalopa – later laval crab stage

Zoeal – early larval crab stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List categories of holoplankton (permanant residents) in terms of their size

A

Smallest - protists (micro-organisms)

Medium - Chaetognatha/arrow worms (1-4cm)

Large - Comb jellies, jellyfish (many metres wide and long)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Give examples of two gelatinous zooplankton

A

medusa and siphonophore

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Give some examples of holoplankton

A

Portugese man o war – colonial hydroid, class next to jellyfish. Gas bladder projects above the water – neuston category

Moon jellyfish

Teptroptimous – long antennae and chaete

Copepods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are some adaptations of arrow worms?

A

Strong hooks around the mouth to catch prey.

Good at picking up vibration in the water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are some adaptations of Ctenophores?

A

Cone rows of scilia

Trailing tentacles with adhesive cells to catch prey – often copepods.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What species dominates the plankton group?

A

The copepods make up 70% of net-collected plankton.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the body organisation of the Copepods

A

Head and first body segment are fused together and contain antennae and mouth parts.

Body segment contains swimming legs and lastly the tail which has no appendages.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do copeppods feed?

A

Antennae swoop once food is deteced on the hairs of the antennae bringing in water and maxillipeds make a circular movement grabbing food with maxillary setules.

Diet preference; two celled chains to single cells and prefer larger diatoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why do zooplankton undertake a diurnal vertical migration, ascending to surface at dusk and descending to depths at dawn?

A
  • Avoid strong uv radiation
  • allow phytoplankton to recover
  • avoid predation
  • conserve energy
  • optimal foraging
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the match/mismatch hypothesis and who proposed it?

A

D.H Cushing proposed the hypothesis.

He noted that climatic factors control the timing and strength of phytoplankton blooms which affects zooplankton feeding and larval fish.

‘Mismatch’ phytoplankton blooms occur earlier/later/reduced than expected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What affects can be caused due to phytoplankton mismatch?

A

When zooplankton and phytoplankton align, you get very good fish stocks. However if PP blooms earlier or later than zooplankton alignment, fish stocks tend to be strongly influenced by timing of prey. Not only for prey but for food for fish offspring.

Plankton mismatch means that prey can differ in size and species which can affect those dependant on them for food.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly