exam3 Flashcards
nekton
fish that can swim against currents in water column
nekton constraints
high Re
-inertial dominate viscous forces
-must minimize pressure drag for fast continual motion
nekton principal members
cephalopods, fish, mammals, sea birds, reptiles
cephalopoda
belong to phylum Mollusca, includes octopus, squid, cuttlefish, nautiluses
characteristics of cephalopods
generally carnivorous,
high developed nervous system with excellent vision, color change,
internal fertilization
chromatophores
pigment cells used to color change and camoflauge
buoyancy using cuttlebone
made of calcium carbonate, many internal chambers that can have gas to liquid ratio regulated to help move up and down the water column
hypnome
cuttle fish use their color changing abilities to confuse or lore prey into them before striking
fish
aquatic vertebrates with gills, fins, and streamline body shapes, very diverse group
osteichthyes
bony fish with true bone skeletons, very diverse, teeth fixed in jaws, single gill opening
chondricthyes
cartilaginous fishes-skates, sharks, rays. replaceable teeth rows, 5 or more gill slits
swimming vs body form
long and narrow-acceleration specialized, round coin/shapes-maneuvering specialist
swimming mechanism
undulation of the body to move- more undulations in eels, tail concentrated in sharks and tuna
oxygen use
Oxygen from water is picked up through mouth and over exposed gills when swimming. more oxygen in water than in gills so diffuses into gills
gill structure
feathery with lots of capillaries and surface area to absorb most oxygen.
countercurrent exchange
blood flows in the opposite direction to the water that flows over gills, gives most favorable gas gradient throughout the body
swim bladder
in most boney fish to regulate buoyancy, can inflate/deflate with oxygen gas to move up or down the water column
gas gland
flexible sac located in dorsal portion of body that controls gas for buoyancy
rete mirabile
intertwined capillaries and veins to help with countercurrent exchange to retain oxygen near gas gland
suction feeding
most common, rapid expansion of mouth to Greate pressure gradient to pull fish into oral cavity
ram feeding
fish opens mouth and swims forward, engulfing prey along with the water surrounding it. ex.whale sharks
suspension feeding
aka filter feeding, feed on particles suspended in the water, don’t swim but rather rely on water movement to bring particles into mouth
gill arch and rakers
gill rakers are on opposite sides of gill arch as the filaments. Used to keep prey in mouth instead of falling out through gills with water
lateral line system
sensory system in fish that detects movement in water thru neuromasts along lateral line, lets them gauge where they are in the water and detect predators
otoliths
cartilaginous part inside fishes ear, allow them to hear and sense vibrations. grow throughout life and can be used to determine fishes age
meopelagic fish
living from 150-2000m deep
adaptations of mesopelagic fish
well developed eyes, large mouths, ventral photophores to camouflage with low light from above
mammals
cetaceans- whales and porpoises
pinnipeds-seals/sealions
mustelids-sea otters
sirenians- sea cows(manatee), dugongs
cetacea
order of aquatic mammals- all whales dolphins and porpoises
homeothermic, reproduce same as terrestrial mammals, posterior strongly muscular-propulsion by flukes
odontoceti
toothed Cetacea, good divers, oral communication is common, bulbous melon filled with oil for eco-location, usually social
mysticeti
baleen whales, whales with tooth plates (baleens) rather than teeth
right whales
continuous ram feeders
rorqual whales
intermittent ram feeders, periodically squeeze water out of large mouth chamber
baleen plates
upper jaw, flat flexible plates with frayed edges arranges in two rows, allows for water to be removed from mouth but allowing prey to stay
pinnipeds
have hair but lack thick blubber of cetaceans, includes seals, sea lions, and walruses
mustelidae
sea otters- relatively terrestrial
diving adaptations
increased volume of arteries and veins
increased blood cell concentration
decrease heart rate and o2 consumption
restrict peripheral circulation to abdominal organs
seabirds and characteristics
often colonial breeders, monogamous, crowded breeding sites, diving underwater to feed, long distance migration
hunting methods of sea birds
- feeding from surface
-plunge diving
-diving from air
-underwater pursuit using fins
-underwater propulsion using feet
reptiles
marine sea turtles- 5 major species
hawksbill, loggerhead, kemp’s Ridley, green, leatherback
food sources of sea turtles
green-sea grasses and benthic invertebrates (finely serrated jaws)
hawksbill- sponges, tunicates, shrimps, squid (narrow head)
Ridley and loggerhead- crush and grind mollusks, shrimps, jellyfish, sea grass (adapted for crushing shells)
leatherback- mainly jellyfish (fine scissor shaped jaws)
life cycles of sea turtles
-females return repeatedly to same beach to Digg nest and lay eggs
-eggs hatch weeks later, crawl to shoreline using light cues and magnetic fields
-predation on hatchlings is high
-adults use magnetic field of each for direction and strength to migrate long distances
domains of life
DNA sequencing of many groups reveals 3 domains of life: Archea, Bacteria, Eukarya
Archaea
distinct lipid-cell membrane, unique ribosomal RNA, resemble Eukarya in RNA transcription and translation - include organisms that live in extreme chemical conditions (often called extremophiles),
Bacteria
have characteristics of traditional prokaryotes, often rod and sphere shapes. Some are autotrophic others heterotrophic (break down organic matter)
Eukarya
cells have a nucleus, nuclear membrane, and cell organelles (mitochondria, plastics in plants), and distinct chromosomes as found in typical animals and plants.
prokaryote
single-cell organism that lacks nucleus. typically much smaller and simpler than eukaryotes-archea and bacteria
bacterias ecological roles
decomposition, nutrient cycling, nitrogen fixation, symbiotic relationships, bioremediation, food web dynamics
autotrophy
self feeding organisms that get nutrients from inorganic substances using photosynthesis
heterotrophy
obtain nutrients from feeding on other living matter: carnivore, omnivore, herbivore, detrivore, parasites
chemoautotrophy
form of autotrophy where they create own energy from inorganic chemicals
chemolithotrophy
oxidize inorganic compounds such as ammonia, nitrate, nitrite, sulfur (bacteria only)
cyanobacteria
occur in single cells and chains, nitrogen fixing, often grow in mats where sediment is anoxic
nitrogen fixation
takes nitrogen from atmosphere and makes it into a form of nitrogen that can be used for many biochemical processes
heterocysts
specialized cells in cyanobacteria that fix nitrogen
diatoms (pennate)
grow as cells, chains of cells, cell wall impregnated with silica, abundant on soft sediments and rocks, readily grazed by many benthic animals
fungi
eukaryotic, often single cells or chains, saprophytic organisms, may be important disease organisms in sea grass
seaweeds
kingdom protista
usually connect to substratum
take up nutrients from surrounding water, do not have extensive support to live in air environment
thallus
entire body of seaweed
holdfast
root-like structure that anchors aquatic seaweeds
stipe
stalk of seaweed between holdfast and blade
frond/blade
frond- blade and stipe together
pneumatocyst
a floating structure that contains gas found on brown seaweed. A seaweed’s thallus may have more than one. They provide buoyancy to lift the blades toward the surface, allowing them to receive more sunlight for photosynthesis.
pigments and storage compound of seaweeds
green- chlorophyll a and b, startch
brown-chlorophyll a and c+ fucoxanthin, lamination, mannitol
red- chlorophyll a and d, phycoerythrin, phycocyanin- Floridian and starch
life histories and alternate generations
gametophyte
A gametophyte is one of the two alternating multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has one set of chromosomes. The gametophyte is the sexual phase in the life cycle of plants and algae.
sporophyte
A sporophyte is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase
seagrasses
worldwide, higher plants, in very shallow water, pollen spreads floating on water, basic structure
rhizome
modified stem that sends roots and shoots from nodes, lets buds grow horizontally
body plan
the basic shape of members of an animal phylum; the general structure each individual organism assumes as it develops.
radial symmetry
involves similar form in respect to center point in all directions. ex. jellyfish
bilateral symmetry
involves a plane of symmetry, with similar form on each side of the plane. also involves an anterior and posterior. ex. worms, lobsters
deuterosome vs protosome
deuterosome-blastopore develops into anus
protostome-blastopore develops into mouth
cleavage
rapid cell division in zygote
blastula
hollow spherical structure arising from cleavage
blastopore
pore inside blastula, when cells migrate to center of blastula and creates an indentation/opening
gastrulation
process in early embryonic development where single layer hollow blastula turns into multi-layered structure called gastrula
endoderm
innermost layer of germ, will create digestive track and part of reproductive system
ectoderm
outermost germ layer that will become hair skin and nails
mesoderm
middle germ layer which gives rise to skeleton muscle and heart
body cavity
fluid filled space inside the body that holds and protects internal organs
coelom
true body cavity, derived from mesoderm
pseudocoelom
body cavity that lies between mesodermal and endodermal tissue
acoelom
organisms with no fluid filled body cavity separating the body wall from digestive tract
relationships of phyla
radial vs bilateral symmetry, protosima vs deuterostomia
protist characteristics
-single autonomous cells with variable symmetry
-diffusion from cell surface
-no gut, body cavity, segmentation, nervous or circulatory system
amoebae
benthic protists, foraminifera, radiolara, engulf bacteria to eat
flagellates
benthic protists, propelled with fewer longer flagella, similar feeding to ciliates
ciliates
benthic protist, elongate, mouth, propelled with outer coating of cilia, feed on bacteria or other smaller protists
phylum porifera
-sponges, either asymmetric or radial,diffusion from cell surface, choanocytes drive water thru pores, organic skeleton of spongin and silica
choanocytes/collar cells
collar like structure with long flagellum, responsible for drawing in food particles and water as well as gas exchange and waste removal
spongocoel
the internal cavity of a sponge where water is drawn into body
spongin
fibrous substance found in skeletons of sponges
spicules
microscopic structures of hard crystal material with fantastic shapes unique to the different species of sponge. They are part of the skeleton that helps give the sponge its shape.
osculum
where water is expelled in sponge
mesohyl
a gelatinous layer between two cell layers
amoebocyte
cells that move within mesohyl that are responsible for digestion, nutrient absorbing and spicule formation
phylum cnidaria
divided into Hydrozoa, Scyphozoa (true jellyfish) anthozoa (corals, anemones)
characteristics of cnidarians
radial symmetry, stinging capabilities, poly and medusa phases, nerve net
polyp
attached to a substrate, vase formed, colonial
medusa
bell shaped, free swimming, tentacles with stinging cells, sexually reproductive
Hydrozoa
Portuguese man of war, egg-larva-polyp-medusa
anthozoa
anemones, corals, normally sessile, asexual and sexual reproduction
nematocysts
specialized cell in cnidarians to sting, for defense or to capture prey
planula larva
free-swimming, flattened, ciliated, bilaterally symmetric larval form
gastrovascular cavity
one opening, responsible for digestion and transportation of nutrients
Platyhelminthes
flatworms
bilateral symmetry, ganglia, two ventral nerve cords, flattened free living worms
ganglia
small bundles of nerves, act as a sort of brain
pharynx
long tubular mouthpart that extends from the body, surrounds food, and tears it into fine pieces before digestion
Nemertea
ribbon worms
bilateral, complete gut, ganglia, carnivorous worms, barbed proboscis to kill prey
Nemotoda
roundworms
special excretory cells, parasitic, only longitudinal muscles
Annelida
polychaetes, oligochaetes, leeches
-bilateral sym, segmentation, brain with ganglia, great diversity of head and locomotive appendages, opposing circular and longitudinal muscle segments
polychaetes
parapodia, couple cm to few mm long, diverse feeding type
parapodia
muscular flaps on sides, setae on ends of parapodia dig into sand for locomotion
setae
small hair like bristles that prevent worms from slipping
living habitat of polychaetes
free living or tube dwelling, inside corals or burrowing
oligochaetes
chitin hairs, earthworms, hermaphroditic,
Phylum Sipunculan
bulbous trunk and long narrow portion, very simple bodies, sometimes tentacles or hooks
Phylum Pogonophora
beard worms, tube like body, inhabit substrates, trophosome
trophosome
cluster of branched tubules to provide habitat for symbiotic relationship with bacteria
Phylum Mollusca
head-foot complex, externally shelled, mantle secretes shell
mantle
soft fleshy outer cover of the body, strengthened with. outer plates
foot
specialized muscle used in digging, moving, and burrowing
radula
structure of tiny teeth used for scraping food particles off a surface into the mouth
bivalvia
class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts
ctenidia
comblike structure, respiratory organ or gill in a mollusk, consisting of an axis with a row of projecting filaments
byssal threads
bundle of filaments secreted by bivalve mollusks that create strong bonds to substrate ex. zebra mussels
gastropoda
coiled shell, large foot, tentacles, and presence of torsion
torsion
the rotation of the visceral mass, mantle, and shell 180˚ with respect to the head and foot
operculum
a lid to help protect the animal when its retracted and needs defended
Polyplacophora
chitons, flattened, have 8 protective interlocking plates, herbivorous
Cephalopoda
carnivorous, arms with suckers, photophores, closed circulatory system
Arthopoda
external chitin cuticle skeleton, segmentation, molting, jointed appendages
Chelicerata
subphylum including sea spiders, horseshoe crabs, scorpions
chelicerae
articulate fangs/jaws special to the chalicerata subphylum
pycnogonids
4 pairs of walking legs, a sucking structure protruding from the head, feeds on colonial invertebrates
crustacea
head w 2 pairs of antennae and mouthpart appendages, large range of feeding adaptations
the Lophophorate phyla
lophophore- horseshoe shaped structure bearing ciliated tentacles around the mouth
Bryzoa
colonial invertebrates with zooids and colonial nervous system
zooids
small individuals that make up a colony
Phylum Branchiopoda
solitary individuals with two calcium carbonate valves attached to bottom with pedicle, feed with ciliated lophophore
Phylum Phoronida
solitary, wormlike, living in vertical tubes, lophophore protruding into water above
Phylum Echinodermata
spiny skin enclosed in an internal skeleton, interlocking calcium carbonate plates, feeding and locomotion on tube feet connected to water vascular system-sea star, sea cucumber
madreporite
light colored opening used to filter water into water vascular system
water vascular system
tube feet being operated by hydraulic pressure in vessels
tube feet
small projections used for feeding and feeling
ampullae
small valve that ssqueezes water into tube foot to extent it
Aristotle’s Lantern
complex mouth operations of sea urchins, calcerous teeth used to scrape algae off rocks
pedicellariae
spines used for protection from predators
Phylum Chordata
notochord, tubular nerve chord, pharyngeal gill arches/slits, post anal tail
Subphylum Urochordata
bilateral, suspension feeders, in and out siphons, barrel shaped body
size classification of benthic organisms
macrobenthos >0.5mm
meiobenthos 0.1-0.5mm
microbenthos <0.1mm
benthic lifestyle categories
Benthos
Epibenthic
Burrowers
Borers
Infaunal, semi-infaunal Benthic swimmers Interstitial
different benthic feeding styles
Suspension feeders
Deposit feeders
Herbivores (macroalgae or microalgae) Carnivores
Scavengers
particle size
measure of current strength median, silt-clay percent (<62mm)
sorting
variation of current strength, poor versus well-sorted sediment
silt-clay fraction
percent of weight of sediment < 62mm
sand ripples
biogenic sedimentary structures
hydromechanical and mechanical digging
thixotropy
hydromechanical burrowing mechanism
penetration anchor
terminal anchor
