Exam #2 Flashcards
Cnidarians
-class Hydrozoa
-class Scyphozoa
-class Cubozoa
-class Anthozoa
Order Milleporina
fire corals, false corals
Order Stylasterina
lace corals
Order Siphonophora
Portuguese man o’war
Characteristics of Hydrozoa
-displays either polyp, medusa, or both
-mesoglea is never cellular
-gastroderm lacks nematocysts
Hydrozoans can be ___ but most are ___.
solitary, colonial
Exhibit polymorphism
dactylozooid, gastrozooid, and gonozoid
Fire corals
-retains characteristics of class Hydrozoa
-colonial calcareous hydrozoan
-unique from most hydrozoans in that a calcareous skeleton and is considered a stony coral
calcium crystal is _____.
aragonite
pores contain one of two different kinds of polyps ->
gastrozooid or dactylzooid
polyps are contained in pores called ________
gastropods and dactylopores
Pores and polyps are arranged in a ____ with ____ surrounding a gastropore in a circular fashion
cylosystem, dactyolopores
Milleporina contain ____
zooxanthellae
____ are mouthless and are arranged around the ____ ; main source of prey capture
dactylozooids, gastrozooids
Lace corals
-genus distichophora, stylaser
-thick layer of tissue overlying skeleton
-pores are star-shaped
-all members have fragile branched colonies
-do not build reef and do not contain zooxanthellae
-calcium crystal is either aragonite or calcite
-lack free medusa stage
____ capture prey, bend downward and deliver prey to ______.
dactylozooids, gastrozooid
Siphonophores
-exist as large pelagic colonies composed of polypoid and medusoid individuals
-many species have a gas-filled sac that acts as a float
-effective predator in the ocean
-most are bioluminescent
-some have lures
-can deflate to sink below the surface
Milleporina
-possess one type of cnidocyte
-contain zooxanthellae
-mustard color with white tips
-do not contain distinct cups or calices
Praya
may be one of the longest organisms on earth
Body plan of siphonophores
pneumatophore, nectophore/nectosome, siphosome, palpons
pneumatophore
gas-filled float
nectophore/nectosome
powerful medusae specialized for moving the colony through the water
siphosome
contains gastrozooids, dactylozooids, and “gonozooids”
palpons
thought to play excretory or defensive role
physonect
all three
cystonect
differs by not having a nectosome
calycophoran
differ in that they dont have a pneumatophore
Reproduction in siphonophores
-an egg gives rise to larval polyp
-this polyp gives rise to the float and forms budding zones
-from these budding zones, the other members of the colony develop always attached to the original
class cubozoa
box jellies, chironex fleckeri - sea wasp
Characteristics for Cubozoa
-square shape
-four evenly spaced tentacles or groups of tentalces
-approx. 20 species known
-have eyes
-24 eyes
-there is one rhopalia on each side of the box-shaped bell, four in all
-they alternate with the tentacles
eyes
-located on the rhopalia which are marginal sense organs which hang from the bell on stalks and are wifhed down by a statolith
-the function for the statolith is not known but it has been proposed as both a gravity-sensing organ and as a weight to keep eyes oriented regardless of body orientation
pit eye and slit eye
on each of the rhopalia there are two lensed eyes (large and small complex eye) an identical pair of pit-shaped ocelli (pit eyes) and an identical pair of slit-shaped ocelli (slit eyes)
Cubozoa reproduction
-sexual reproduction
-fertilization takes place inside the female after a male has passed a sperm packet with his tentacle
-eggs develop into planula
-after a few days as free-swimming planula, they settle and develop into polyps
-after a few months of feeding, polyps metamorphose into a single medusa
Cubozoa venom
-the most deadly in the animal kingdom
-500,000 nematocysts/tentacles
-toxicity and amount of venom vary per species
-cubozoas are active predators
Class Scyphozoa
-frequently referred to as jellyfish
-typically possess tentacles and most with nematocysts
-medusa stage is dominant stage and polyp form is reduced to a small larval stage
Characteristics of Scyphozoa
-one sessile order
-gonochoric
-lack a velum which is the shelf of tissue around the the margin of the bell of the hydrozoan and cubozoan medusae
-most are dioecious
The ____ may reproduce asexually by ____ or ____ of cysts.
scyphistoma, budding, formation
primary microplastics
pieces of plastic less than 5 mm long; some are “micro” by design such as those used in cleansers; nurdles are included
secondary microplastics
results of bigger plastic pieces weather down
____ has been shone to be lethal to juvenile corals
Oxybenzone (BP-3)
Zooxanthellae
dinoflagellate, are able to soak up the toxin but corals without the symbiont feel the full affects of the toxin which is “activated” by sunlight (oxybenzone is designed to dissipate light energy as heat but cnidarians metabolize oxybenzone in such a way as to form damaging radicals when exposed to sunlight).
Coastal developments and corals - How?
o Habitat degradation
o Sand erosion, land retreat, and sedimentation
o Changed water flows
o Chronic runoff
o Sewage effluent
o EDCs and the microbiome
Two ways the sea can rise…
thermal expansion and increased melting of ice sheets
What’s in it for the Zooxanthellae?
- Protection
- A constant environment
- Nitrates, phosphates and ammonia
What’s in it for the polyp?
- Nutrients from photosynthesis
- Calcification
- Zooxanthellae remove the carbon dioxide that is an end product of calcification
Symbiosis
- Parasitism
- Commensalism
- Mutualism
Algal-invertebrate symbiosis
- Most hermatypic corals are symbiotic with a dinoflagellate called zooxanthellae
- Soft corals, jellyfish, giant clams, sponges, protists and nudibranchs also have evidence of this symbiosis with zooxanthellae
- Cyanobacteria have been discovered to coexist with zooxanthellae in Montastrea cavernosa
Polyps can control the amount of ____ that occurs by the distance they extend their tentacles
photosynthesis
Coral brooders can endow their ____ with a starter culture; broadcast spawners must incorporate free-living dinoflagellates
planula
Bleaching
- Maintaining the zooxanthellae comes at a metabolic cost to the corals
- Under stressful conditions, the coral will expel the zooxanthellae. The coral tissue is still live and healthy, but the bleaching event indicates that the coral is under stress and is therefore vulnerable to disease
- Some expulsion of zooxanthellae on a regular basis is normal
Sunscreen
Corals produce their own sunscreen to protect against UV – mycosporine-like amino acids (MAAs) – made from compounds produced by the zooxanthellae.
MAAs
mycosporine-like amino acids
Coral calcification
the complex process by which corals take calcium from seawater and form aragontie or calcite crystals to be used in skeletogenesis
Carbonate chemistry
another reason reefs exist in warm waters more than in cold water
organisms that secrete CaCO3 do so in one of two crystalline forms
aragonite, calcite
differences in the two crystals
- Aragonite is structurally stronger than calcite
- They differ in stability at different temperatures and pressures
- Aragonite more readily precipitates in warm water supersaturated with CaCO3 and is less stable in cooler water or freshwater
- Over time, aragonite dissolves or recrystallizes, so calcite predominates in ancient limestone
Amounts of CO2 that can initially dissolve depends on temperature, pressure, concentrations of other dissolved materials
- Cold water holds CO2
- Deep water holds more CO2 due to pressure
- Higher salinity holds less CO2
- Tropical waters hold less CO2(warm water)
Therefore, the more carbon dioxide that is dissolved into the water, the more readily the water can dissolve CaCO3. This makes warm water tropical oceans more conductive to precipitation of CaCO3 and colder, deeper water more apt to dissolve CaCO3.
- CaCO3 doesn’t behave like table salt and sugar which dissolve better in warm water
- CaCO3 is more soluble in cold water
The deeper you go, the more _ stays in the solution
CO2
The surface of tropical oceans is the best place for ____ precipitation and coldwater deep ocean is the worst.
CaCO3
Calcification takes place beneath the _ layer of the coral polyps
epithelial
ECF
Calcium enters through the gut and then is actively transported to this interstitial watery place called the extra cytoplasmic calcifying fluid (ECF).
Three possible ways for CO3 to enter
- Bicarbonate enters gut, combines with a proton to form CO2. The CO2 then freely diffuses across the epithelium where it is converted the carbonate.
- Bicarbonate is pumped across epithelium to ECF and there is converted to carbonate
- Respiration of coral
- Ca++ - ATPase another possibility
Coral polyp and Zooxanthellae help by:
- Raising the supersaturation of Ca and carbonate to point where precipitation is likely
- They maintain a fresh crystal face of aragonite to act as seed
- They may partially exclude Mg, PO4-, and organics that inhibit crystal formation
- They help direct crystallization with their own proteins and polysaccharides secreted in ECF
Some organic molecules (possibly proteins) may help in calcification by controlling the rate of ________ or by ________ with it and ferrying it to act in skeletogenesis.
precipitation, binding
Reefs as a Carbon Sink
- Calcification can produce carbon dioxide but this can be consumed by the zooxanthellae
- But global warming…The sea level is predicted to rise 6 cm per decade over the next century with an average of 3-10 per decade. Reef accretion estimates range from 1 10mm/year with 10mm/year accepted as maximum
- Also as partial pressure of CO2 increases, calcification decreases. So as sea levels rise, reefs need to build to keep up.
Electro mineral accretion experiments
- When an electric current is run through submerged metal, calcium carbonate settles on it
- It works like a battery with one side being the cathode and the other being the anode
- Mineral will be attracted to each side and hydrogen bubble will accumulate on the cathode side and bubbles of oxygen and chlorine gas will accumulate on the anode
- Later, people attach corals to the metal mesh and the electrical current helped them have quick access to the calcium carbonate
- Corals that grew this way seemed to be more resistant to stress and disease
Artisanal fisheries
- Sustainable
- Important sources of protein
- Historical and cultural significance
Fish – Inverted food chain
- Groupers – predatory; vulnerable due to spawning aggregates
- Snappers
- Parrotfish
Methods
- Artisanal, subsistence, semi-industrial
- Mothership (factory ship, very large, carry smaller ships)– dory for pelagic fish; handlines
- Longline
- Traps – fish and inverts – pots for octopus
- Spears and spear guns
- Recreational
Invertebrates
- Conch
- Beche-de-mar
- Octopus
- Giant clams
- Trochus
- Pacro – chitons
- Spiny lobster
Effects of Overfishing
- Removal of large apex predators changes diversity
- Growth overfishing – the removal of small individuals that minimize overall yield – “low hanging fruit”
- Recruitment overfishing – removing large, reproductively mature fish
- Ecosystem overfishing – targeting one species and then another
Fishing down the food chain
“the antithesis to sustainable harvest and is clear evidence of ineffective management.”
The effects on the corals?
- Reduction in herbivores
- Unchecked urchin populations cause increased bioerosion
- Upset balance
Management of reef fisheries
- Catch quotas – transferable quotas
- Minimum/maximum size limits
- Gear restrictions
- MPAs – “allee effect”
- Restocking
Palms
- Arecaceae – one of the largest botanical families – 202 genera and 2600 species
- Mostly prefer high humidity but can tolerate some temperate and even cold climates
Palm products and usages
- Oil – food, cosmetic product, energy source\
- Sugar
- Wine
- Seeds and fruits – coconuts and dates
- Ornamental landscaping
- Honey
- Wax
- Fibers from leaves and coconuts can be made into hats, handbags, brushes, shoes, strings, ropes, carpets
Common features of palms
- One or several trunks with a crown and clusters of flowers – some have thorns on all parts including roots
- Leaves grown from the top of the trunks
- Some may have swollen areas at the base or along the trunk
- Some have a shallow root system
- The crown shaft at the top may be green, red, or orange
- There are some climbing varieties
- Trunk can be 1-50 meters
- Trunk diameter can be 1 cm to more than a meter
- There are some palms with no trunks
- Most do not have branches although damage to the apical meristem can cause branching
Growth of palms
- Maintains diameter all the length of the trunk
- Angiosperms that produce flowers
- Can be monoecious or dioecious
- Almost all develop from seeds
- Roots sprout out of two eyes and sink into the ground, a green shoot sprouts out of the third eye
- Growth takes 5-6 years
Coconut palm
- One species – coco
- Takes a year to develop from a flower into a ripe nut
- Unripe green coconut has juice or milk that can be drunk
- Ripe coconut is brown and a thin layer of meat or pulp
- As it ages, the meat layer thickens and the juice turns to tasteless water
- Meat can be shredded and eaten or dried into copra from which oils can be extracted
Coconut apple
digests the meat and provides it to the sprout
Copra
- flesh of the coconut
- Made into cakes
- Can be fed to livestock
- Main source of edible fat in Europe in 1860’s due to shortage in dairy fat
- Coconut oil makes up 20% of all vegetable oils
- Used in soaps, detergents and cosmetics
Heart of palm
-kills the tree
-made from the bud of a growing palm tree
Mangroves
- Salt-tolerant plants
- 69 species worldwide
- Different adaptations to salt
- Reproduce by viviparity – seeds develop fully while still attached to the tree; the fully developed seedlings fall to the water and float root-side down until they reach shallows and take root
Adaptations
- Roots can prevent absorption by filtering it out
- The tree can concentrate salt in older leaves which then die, fall, and take the extra salt with them
- Some have salt glands on leaves which secrete the salt to have it washed away by rain
Red mangrove
multiple prop and drop roots; dark green leaves and reddish bark
Black mangrove
pneumatophores (knees); bark is dark and scaly; leaves may be furry on the underneath
White mangrove
scaly, yellowish bark and yellowish-green leaves; fruit is a reddish drupe; there are no knees or prop roots, nectaries that secrete a sugar for insects to come to eat
Buttonwood
hardy species of mangrove
Oxygen
- Anaerobic conditions are not a problem for mangroves
- Prop roots in red mangroves can collect oxygen through lenticels
- Black mangroves have pneumatophores which are straw-like prop roots
- Most mangroves have openings that connect with airways (aerenchyma) inside the trunk that can distribute air
Lenticels
pores or cracks in bark and in prop roots
Water
- Waxy leaves prevent water loss due to transpiration
- Zonation
Mangrove islands
sedimentation can add land mass, which can create an island
Mangroves - seagrass - reefs
Mangroves, ecologically speaking
- Traps terrestrial runoff
- Large microbial community
- Nutrient exporter to reef
- Buffer
Seagrass
- Submerged aquatic vegetation; angiosperms (flowering)
- 60 species found worldwide
- Photosynthetic
- Ecosystem engineers
- Nutrient importers
African Dust
- Dust created by long-term droughts in the Sahel desert region of Africa, plus questionable farming practices and the drying of Lake Chad
- The dust is lifted 15,000 feet into the air by desert winds and then carried across the Atlantic
- The dust mostly affects Florida and the Caribbean but can reach as far north as Maine and as far west as Texas.
- Now 1 billion tons annually of African dust are carried westward each year
What does African dust do?
- Carries bacteria and fungi of which 25% are plant pathogens and 10% are opportunistic human pathogens
- Has been linked to asthma in humans
- Contains pesticides that are banned in the US
- It is currently being tested for the heavy metals Cu, As, Pb, Se, Cd
CITES
convention on international trade in endangered species of wild fauna and flora.
The Endangered Species Act
is the method by which the U.S. follows through with its commitment to the CITES recommendations.
Appendix 1
includes species threatened with extinction and could be affected by trade
Appendix 2
not presently threatened with extinction but have the potential if their trade is not regulated
Appendix
listed by a range country in an attempt to obtain international cooperation in controlling trade
Species need to be listed if:
- Trade exceeds the sustainable level
- Trade is reducing the population so other threats may affect them
- Trade impacts its role in its ecosystem
The Lacey Act
bans the import of wildlife and products that were taken illegally in their country of origin.
Acropora cervicornis
is now on the IUCN red list due to an 80-98% reduction in some parts of the Caribbean. The ESA still lists them as threatened.
Types of MPAs
- National marine sanctuaries
- National parks
- Wildlife reruges
- State parks
- Conservation areas
- Fishery management closures
Five functional terms to categorize MPAs
-conservation focus
-levels of protection
-permanence of protection
-constancy of protection
-scale of protection
Conservation focus
- Natural heritage sites
- Cultural heritage
- Sustainable production
Level of protection
- Uniform multiple-use
- Zoned multiple-use
- Zoned with no take areas
- No take
- No impact
- No access
Permanence of protection
- Permanent protection – like MPAs and all national parks
- Conditional – needs to be renewed
- Temporary – like with fisheries closures
Constancy of protection
- Year-round
- Seasonal
- Rotating
Scale of protection
- Ecosystem – most marine sanctuaries, national parks, and national monuments
- Focal resources – like marine sanctuaries and wildlife refuges
LOM
living organic matter
DOM
dissolve organic matter
SPM
suspended particulate matter
Uptake of corals is accomplished by either ____ or ______.
diffusion, active transport
Under low light condition
- Increase in protein and lipids per unit surface area
- Increase in zooxanthellae density and pigment
- Increase in photosynthetic capacity
- Some species may have an increase in skeletal growth
Under high light conditions
- Increase in protein
- Increase in zooxanthellae density and pigmentation
- Increase in bulk skeletal growth
- Increase in rates in light and dark calcification
Corals that have recently bleached show a reductin in ____ indicating that they are surviving on stored nutrients after loss of photosynthesis.
lipids
Filter feeding
-Corals that “filter-feed” also show a higher survival ability of bleaching.
-Amino acids from “filter-feeding” are shared with the zooxanthellae.
Flamingo tongue
snail that lives in the coral reef
Quadrate
