Holo and Meroplank Flashcards
(99 cards)
1
Q
What is holoplankton?
A
Permanent members of plankton showing low diversity but high abundance.
2
Q
What are 4 examples of protozooplankton?
A
Heterotrophic flagellates, ciliates, radiolarians, and foraminiferans.
3
Q
What is the size range of heterotrophic flagellates?
A
2-5um
4
Q
How do heterotrophic flagellates consume prey larger than themselves?
A
Pallium feeding, tube feeding and direct engulfment.
5
Q
What is pallium feeding?
A
A veil of cytoplasm, the pallium, surrounds prey. Digestive enzymes are secreted onto the enveloped prey. Only digested material is brought into the cell body as the pallium is retracted.
6
Q
What is tube feeding?
A
Insert tube into prey to suck out cytoplasm.
7
Q
What are two examples of dinoflagellates?
A
Noctiluca scintillans, Karlodinium veneficum.
8
Q
What are ciliates?
A
Protists that move using cilia.
9
Q
What are the two forms of ciliates?
A
Loricate (shelled) or aloricate/oligotrich (no shell).
10
Q
What are the 5 orders of Radiolarians?
A
Acantharia, Nassellaria, Spumullaria, Collodaria, Taxopodia.
11
Q
What features aid buoyancy in radiolarians?
A
Vacuoles, lipid droplets and pseudopodia.
12
Q
What are the mineral skeletons of radiolarians made of?
A
Strontium sulphate or silica.
13
Q
What are some key features of foraminiferans?
A
Cell is surrounded by a calcium carbonate shell pierced with pores, pseudopodia present, omnivores using reticulopodia to capture food.
14
Q
What is the purpose of bioluminescence?
A
Feeding: attract prey towards mouth, light up the area to see better. Attract mates: identify between males and females, communicate to mates. Self-defence: startle and distract, camouflage using counterillumination.
15
Q
What are the mesopelagic features present in scyphozoans (order Coronatae)?
A
Red colouration, direct development, bioluminescence.
16
Q
What are two examples of deep sea scyphozoan jellyfish (order Coronatae)?
A
Atolla sp. and Periphylla periphylla.
17
Q
In class Hydrozoa, order Siphonophorae, what specialised individuals make up the colony?
A
Pneumatophore, nectophore, dactylozooid, gonozooid, and gastrozooid.
18
Q
What does Siphonophore: Cormidium mean?
A
1 unit of zooids within siphosome.
19
Q
What are the 3 taxonomic groups of the order Siphonophorae?
A
Physonect, Cystonect, Calycophoran.
20
Q
How do ctenophores swim?
A
Using comb plates (fused ciliary plates).
21
Q
Why are sea butterflies/heteropods (Thecosomata) vulnerable to ocean acidification?
A
Most have thin calcified shells.
22
Q
What does the Order Thecosomata consist of?
A
Heteropods, sea butterflies.
23
Q
What has the foot developed into in sea butterflies?
A
2 wing-like lobes/parapodia which are used to swim through a flapping motion.
24
Q
What does the Order Gymnosomata consist of?
A
Pteropods, sea angels/slugs.
25
How do arrow worms feed? (phylum Chaetognatha)
Capture prey using chitinous grasping spines around mouth, active carnivores and active darting swimmers.
26
What is used for species ID of arrow worms?
Overall length, relative length of features, mouth parts and fin positioning.
27
What are some key features of arrow worms?
Bilaterally symmetrical, transparent, lateral and caudal fins, cerebral and ventral ganglia present, hermaphrodites.
28
What factors determine size and type of prey a chaetognath can eat?
External factors- light (photoreceptive eyes), prey size and motility, swimming speed relative to prey, size of grasping spines and mouth (gape-limited predation).
29
What are the 3 orders of Class Thaliacea?
Salps, doliolids, pyrosomes.
30
What are the differences between salpida and doliolida?
Salpida; muscle bands incomplete, two distinct body forms, jet propulsion creates feeding current. Doliolida; complete muscle bands, cilia creates feeding current, typically smaller.
31
What are the 2 distinct body forms of salps?
Solitary asexual oozoid and colonial sexual blastozooid.
32
How do larvaceans feed?
Secrete mucus house every 3 hours to filter feed nanoplankton.
33
What organisms make up Class Appendicularia?
Larvaceans.
34
How do larvaceans reproduce?
Direct development.
35
What are the families of Class Appendicularia?
Oikopleuriidae, Fritillariidae, Kowalyeskiidae.
36
What are the characteristic features of crustaceans?
Segmented body divided into three main parts - head, thorax, abdomen; pairs of jointed legs; a hard exoskeleton made of chitin, protein and calcareous material; two pairs of antennae.
37
What are the key features of ostracodes?
Mostly warm water, herbivorous filter feeders, carapace bivalved with adductor muscle.
38
What does parthenogenetic mean?
A form of asexual reproduction where the embryo develops from an unfertilised egg, but also has sexual generation with 'resting' eggs.
39
What are some key features of the hyperiid amphipods (Order Amphipoda, Suborder Hyperiidae)?
2 pairs of compound eyes, carnivorous, no carapace, clean body segments, body laterally flattened.
40
What are key features of the mysid fauna (crustacea, mysidacea)?
Moveable eyes on the peduncle, thoracic limbs for swimming, omnivorous, globally distributed.
41
What are the key features of euphausiids? (Crustacea, Euphausiacea)
Mostly herbivorous filter feeders, gills at base of thoracic limb, not completely covered by carapace. Carapace fused with cephalothorax. No statocyst.
42
Why are krill considered to be 'significant' members of ecosystems in high latitudes?
High biomass, food for megafauna, biogeochemical cycling, commercially harvested.
43
How many orders of copepods are there, which 3 are the most abundant/important?
10 - Calanoida, Cyclopoida, Harpacticoida.
44
Describe the anatomy of copepods.
No carapace, but clear divisions between head, thorax and abdomen. Cephalosome and metasome together are called the prosome. Compound eye absent, well-developed antennae and antennules, urosome lacks appendages, separate sexes.
45
Describe the life cycle of copepods.
Eggs spawned or brooded in egg sac, egg hatches into a nauplius - 6 naupliar stages (NI - NVI), 6 copepodite stages (CI - CVI), C VI = adult (separate sexes).
46
Which group of plankton are considered the insects of the sea?
Copepods.
47
What are the distinguishing features of calanoid copepods?
Long 1st antennae, biramous 2nd antennae, single egg sac, joint is between 5th and 6th segment.
48
What are the distinguishing features of cyclopoid copepods?
Shorter 1st antennae, uniramous 2nd antennae, two egg sacs, joint is between 4th and 5th segment.
49
What are the distinguishing features of harpacticoid copepods?
Very short 1st antennae, biramous 2nd antennae, mostly benthic, wide abdomen.
50
What factors affect barnacle settlement to the benthos?
Time of day, current- velocity and direction, surface contour and angle, presence of adults, depth, particle size, texture.
51
Describe the life cycle of a true jellyfish.
1. Adult medusae reproduces sexually to release eggs and sperm that are fertilised in the water column or near the mouth. 2. Larval stage = the planula- non-feeding life form. 3. Metamorphizes into a polyp reproducing asexually to produce more polyps (in summer) or new juvenile medusae (winter).
52
What is the nutritional mode of lecithotrophic larvae?
Non-feeding larvae, possess a yolk reserve, remain in plankton for a few days.
53
What is the nutritional mode of planktotrophic larvae?
Feeding larvae, well-developed feeding and swimming organs, remain in plankton for several weeks.
54
What are the two forms of ciliated larvae?
Downstream and upstream.
55
Describe downstream larvae.
Mouth located behind principal ciliary band, cilia beat towards mouth, locomotory and feeding currents coincide so can feed as swim. e.g. trochophore larva.
56
Describe upstream larvae.
Mouth anterior to principal ciliary band, cilia beat away from mouth, locomotion currents can't be used for food capture directly, swim slowly and large SA e.g. pluteus larva.
57
What are the 3 different classifications of planktonic larvae?
Teleplanic, Actaeplanic, Anchiplanic.
58
What is Teleplanic?
Planktonic periods of 2 months or more, high dispersal potential, e.g. gastropods, bivalves, crustaceans.
59
What is Actaeplanic?
Coastal plankton, 1 week-2 months, 70% of temperate sublittoral species, e.g. clownfish.
60
What is Anchiplanic?
Plankton period of hours to days.
61
What are the risks of planktonic larvae?
High mortality from: surviving critical release and return phases, predation in the water column, and transport away from suitable site.
62
What are the rewards of planktonic larvae?
Increased gene flow, dispersal of population, reduced predation from adults, reduced competition for space.
63
What is the role of planktonic larvae in 'island' populations?
Different species/taxa will have different strategies to communicate in different systems. Chemical signatures from hydrothermal vents are followed or ocean currents/hydrodynamic currents are used for transport.
64
What larvae is shown in Phylum Cnidaria?
Planula larvae - forms from fertilised egg of medusa (scyphozoans, hydrozoans) or a polyp (anthozoans).
65
What are the two types of metamorphosis shown by cnidarian planula larvae, depending on the species?
Metamorphoses directly into a free-swimming, miniature version of the adult form (such as in open-ocean scyphozoans), or navigates through the water until it reaches a hard substrate where it anchors and grows into a polyp.
66
What are Ephyra?
Ephyra are new juvenile polyps produced by strobalisation in the phylum cnidaria.
67
What larvae do polychaetes have?
Trochophore larvae (ciliated, downstream).
68
What is the development pathway of a polychaete?
Trochophore, metatrochophore, pre-settlement post-larvae stage.
69
If larvae look similar, such as Polychaete trochophore larvae, how would you identify them in a sample?
Knowledge of adult distribution in the benthos, time of year when present in water (related to breeding cycle), known biogeography of potential species, use a dichotomous taxonomic key to identify features, molecular analysis of sample tissue.
70
What larvae do molluscs have?
Trochophore and veliger larvae.
71
What are features of the veliger larvae in molluscs?
Adult organs, velum for swimming, feeding and gas exchange. The late veliger stage before settlement is the pediveliger when the velum is resorbed.
72
What is the difference in larval forms of gastropods and bivalves?
Gastropods have a larval shell from torsion and coiling. Bivalves from a small version of the adult-veliconcha.
73
What larvae do lophophorates have?
Cyphonaute larvae. (feeding)
74
What larvae do echinoderms possess?
Pluteus and auricularia larvae.
75
Which groups of echinoderm larvae do not possess spicules?
Hemichordata and asteroids.
76
Which groups of echinoderm larvae possess tiny spicules?
Holothuroids.
77
Which groups of echinoderm larvae possess developed skeletons?
Ophiuroidea and Echinoidea.
78
What larvae do crustaceans possess?
Nauplius larvae.
79
Describe nauplius larvae in Cirripedia/barnacles.
2 rostral and 1 caudal spine, naupliar larval stage lasts 2-3 weeks. Cypris is the settlement stage.
80
What larvae do decapods possess?
Nauplius, zoea, and megalopa.
81
Why do porcelain crab zoea have such long spines?
Predator deterrence by increasing size relative to predator gape, increases surface area to aid flotation, helps the individual to swim laterally (forwards and backwards).
82
What is ichthyoplankton?
Fish eggs and larvae.
83
What is the flexion in ichthyoplankton?
The flexing of the notochord during caudal fin development.
84
What are plankton larvae that do not feed within the plankton and generally remain in the water column for only a few days described as?
Lecithotrophic.
85
Where is the coronate jellyfish Periphylla periphylla found?
Mesopelagic.
86
Including the egg, how many life stages are there in the copepod life cycle?
13.
87
Which pelagic tunicate possesses solitary asexual oozoids, colonial sexual blastozooids, incomplete muscle bands and larvae without tails?
Salps.
88
What is the ciliated foot used for?
Locomotion.
89
Based on length of time spent in the water column, place the following larval types in order starting with the shortest duration first: Anchiplanic, Actaeplanic, Teleplanic.
Anchiplanic, Actaeplanic, Teleplanic.
90
The Portuguese man o' war is a member of which Class of the sub-phylum Medusozoa?
Siphonophorae.
91
Which protist is used as a proxy for climate change via the fossil record?
Foram.
92
Which phylum uses sticky colloblasts to capture prey?
Ctenophores.
93
Place the following 3 stages of crustacean larvae into increasing order of development: Megalopa, Nauplius, Zoea.
Nauplius, Zoea, Megalopa.
94
Which Class of crustacean has a bivalved 'shell' or carapace?
Ostracod.
95
Which two phyla have a trochophore larva?
Mollusca and Polychaeta.
96
What physical features do you see when a polychaete trochophore larvae develops into a metatrochophore larva?
Segments.
97
Can a 'downstream' ciliated larva swim and feed at the same time?
Yes.
98
What are the common names of ctenophores?
Sea walnuts and gooseberries.
99
Which features can be used to distinguish between a mysid and a krill?
Eye stalk presence, presence or absence of sensory statocyst and carapace fused with cephalothorax or not.
