BI 260 Exam 2

3 sponge body types

3 sponge body types

asconoid (simple tube), syconoid (folded on itself), leuconoid (very complex)

Copepoda

crustacea

• small with similar apendages

• first antenae are used to move and swim

• common and significant in plankton pop

Thecostraca

crustacea

• barnacles look like mollusks becasue bodies are envlosed in calcareous plates

• featery appendages filter water

• filter feeders

• very spacific habitat preferences

Amphioda

Malacostraca, crustacea

• curved bodies

• appendages specialized to function

• found in shore debris seaweek, burrowing, or living amongst the plankton

Isopoda

Malacostraca, crustacea

• similar to amphipoda

• non specialized legs

• body is flat

• often parasites of fish

Euphasiacea

Malacostraca, crustacea

• krill/euphasids

• head is fused with body segments to form carapace tat covers anterior half of body armor

• filter feeders

  • diatoms and other plankton

• common in polar waters

• supports polar food webs

3 subclasses of gastropods

prosobranchia, pulmonata, opisthobranchia

4 lifestyles of polychaeta

crawling: developed eyes, backstroke form of movement.

burrowing: use muscles to burrow into sediments, occupy fixed burrows or make their own

tube dwelling: form tube and live entire life there, some may lose some metamerism, create tube using mucus and other secretions.

pelagic: can swim to an extent.

Crustacea

Arthropods, Protostone, Bilateria

Defining Characteristics

• head and thorax and be fused (cephalothorax)

• head as five pairs of appendages

  • two antennae, mandible (jaw), two pairs of maxillae

• have a larval form (nauplius)

• three pairs of appendages and one medial eye

Feeding

• filter feeding is common/often scavengers

• stomach grinds the good, and is connected to digestive gland (absorb nutrients)

• blood is free flowing (open circulatory system)

Brain and Behavior

• Nervous system

• small simple brains, sensory organs=ventral nerve cord (centralized, ladder-like)

• have compound eyes, a keen sense of smell, and statocysts (marble apparatus?) for balance

• visual and olfactory signals for courtship and contests

• can form societies (eusocial)

Reproduction

• sexes are seperate (gonochoristic)

• male uses special appendages to directly transfer sperm

• Females will carry eggs with them using pleopods

• develop into nauplis larvae

Malacostraca (Decapoda, Euphasiacaeda, Copepoda, Thecostraca

amphipoda

flattened along the anterior/posterior axis, gills are thoracic, and can have large eyes. can be pelagic or benthic.

accomplished burrowers (malacostraca)

Annelida (3 orders)

all have metameric segmentation (one segment is similar to the next) and cephalization.

Hirudinea (leeches) Oligochaeta and Polychaeta

Anthozoa

Sea anemones and corals.

Defining Characteristics

• Have mesentary partitions to increase surface area.

• Lots of symbionts, including zooxanthellae and clown fish.

• some anemones move their tentacles to optimize exposure to sunlight for their photosynthetic symbionts.

Anthropoda, Chelicerata(subphyla) (2 classes)

Merostomata, Pycnogonida (sea spiders)

Arthropoda

Crustacea (lots of classes)

Defining Characteristics

• characterized by 5 sets of head appendages: 1st antennae set, 2nd antennae set, mandible set, 1st maxillae set, 2nd maxillae set.

• a thorax and a abdomen segmented; can be fused

• an oculi larvae

Ascidiacea

Commonly known as sea squirts or tunicates.

Defining Characteristics

• intertidal and tidal zones, the 'tunic' is made of cellulose, has 2 openings, one inhalant and one exhalant that filter the water over a mucus-covered basket and also the gills.

• The mucus is produced by an endostyle and spread by cilia. Mucus catches food particles.

• Larvae are pelagic, the adults are attached to the bottom(Sessile) (Urochordata)

Asteroidea

sea stars. exclusively saltwater. bottom dweller.

Defining Characteristics

• Has an internal skeleton of calcareous ossicles inside the soft tissue.

• Water vascular system, used to create suction cup from tube feet, water comes in through madreporite.

• oral and aboral surfaces.

• gastrovascular glands and gonads in all arms.

• eat bivalves by using suction cup feet to slowly pry apart the shells.

• Regenerative power as long as part of central disc is included.

Carnivorous

Berioda

Looks like a tube, open on one end.

Eats lobates (ctenophores)

Bilateria

Protostomes and Deuterostomes

Defining Characteristics

• three tissue layers: endoderm, mesoderm, ectoderm

  • mesoderm allows for body cavity (coelom)

• Specialized tissue/cells that produce organs

• Bilateral symmetry

• Early specialization of blastula (hollow ball of cells)

Two clades within Bilateral

Protostomes and Deuterostomes

Protostomes

“mouth first”

• cell cleavage occurs through spiral cleavage

• masses of mesoderm split to form body cavity

• blastopore (ollow opening) developes into the mouth

Ecdysozoa

1 of 2 Protostone

Defining Characteristics

• all molting animals (cuticle)

  • process is called ecdysis

• largest group in animal kingdom (insects, spiders, crustaceans)

Arthropoda

Ecdysozea, Protostone

Defining Characteristics

• segmented bodies with jointed appendages

• developed exoskeleton

Deuterostomes

“mouth second”

• cell cleavage occurs from radial cleavage

• folds of archenteron form mouth

• blastopore becomes anus

Porifera vs Bilateral

Porifora

• no symmetry

• no tissue just cells

  Bilateria

• three tissue layers: endoderm, mesoderm, ectoderm

• Specialized tissue/cells that produce organs

• Bilateral symmetry

Bilateria

• three tissue layers: endoderm, mesoderm, ectoderm

  • mesoderm allows for body cavity (coelom)

• Specialized tissue/cells that produce organs

• Bilateral symmetry

• Early specialization of blastula (hollow ball of cells)

Decapoda

Malacostraca, Crustacea

Defining Characteristics

• have 5 pairs of legs (pereiopods)

• front legs (cheliped) is specialized to have claws

• 3 pairs of maxillipeds (filtering food)

Shrimp

• scavenger

• elongated abdomens

Crab

• life outside the water

• rounder stomachs

• also scavengers

Lophotropozoans

Protostomes, Bilateral

Defining Characteristics

• lophophore feeding device

  • U shaped ring of tenticles covered with cilia used t capture small food and oxygen

• trochophore larva

  • free swimming larvae

  • band of cilia allows them to swim

Mollusca

Lophotroposoans

snails, clams, octopuses

Defining Characteristics

• Soft velvety body

• covered by manltle (organ that secretes the shell)

• small teeth (radula) used to feed

• ventral muscular foot

Feeding

• have digestive glands

  • release digestive enzymes

• Grazers

  • some can take up chloroplasts/organelle from what they are grazing and can then photosynthesis (kleptoplasty)

• Filtered and sorted from the water using silica (suspension feeding)

• crystaline style releases enzyme in the stomach

Body Systems

• circulatory cystems that carries nutrients and oxygen

6 Major groups of mollusks

Polyplacophora, Monoplacophora, Gastropoda, Scopophoda, Cephelopoda

Gastropoda

Mollusc, Lophotropozoa

• coile mass of vital organs enclosed by shells

• ventricle creeping foot

Bivalves

Mollusc, Lophotropozoa

• laterally compressed

• shell with two parts (valves)

• uses gills to feed

• abductor muscles to close valve

  • for protection: pysical and from drying out

Reproduction

• external/braodcast spawning

Cephoalopoda

Mollusc, Lophotropozoa

• no hard protective shell

• all predators

• foot= arms and tentacles with suckers to capture pray and movement

• ink sac

• have siphon (can be used to move by jet propulsion)

Feeding

• two-part beak (rostrum)- functions as a bird beak

• predator

Reproduction

• internal

• male deposits spamatophore

Body System

• closed circulatory system, blood remains in vessels

• flow to tentacles and brain

• Brain

  • sense organs/tactiles

  • input info from surrounding/output behavior

• Eyes

  • convergent evolution: similar human eyes that are camera-like and can focus

  • focus by moving lens back and forth

  • no fibers between lens and photoreceptor=no blind spot

Polyplacophorans

Mollusc, Lophotropozoa

• eight overlapping shell plates

• shallow, hard botton environments

Reproduction

• external/braodcast spawning

Monoplacophorans

Mollusc, Lophotropozoa

• deep water environments

• one single cone like shell

Reproduction

• external/braodcast spawning

Scaphopods

Mollusc, Lophotropozoa

• tusk shell- looks like an elephant tusk

• sandy muddy environments

Feeding

• use scent to find prey or sit and wait

• shoot radular tooth (looks like harpoon) and poisons (conotoxins) their prey

Reproduction

• external/braodcast spawning

Hemicordata

Deuterostomes, Bilateria (sister to echtodermata)

Asteroidea

Echinodermata, Deuterosome, Bilateria

sea stars

Defining Characteristics

• tube feet protrude from ambulacral grooves on oral surface

• carnivorous: bivalves, snails, barnacles

• use feet to pry open shells

• excrete stomach to liquify and capture prey

Ophiuroidea

Echinodermata, Deuterosome, Bilateria

Brittle star, basket stars

Defining Characteristics

• swift, snowflake movements with arms

• variety of feeding: predation, deposit-feeding, scavenging, suspension feeding

Echinoidea

Echinodermata, Deuterosome, Bilateria

sea urchins, sand dollars

Defining Characteristics

• rocky substrate/kelp forests

• endoskeleton is called a test with movable spines

• five rows of ambulacral grooves on out surface

• move by their spines and their tube feet

• Aristotle lantern (mouth part)

• herbivorous (detritous, suspension feeding, pradtion)

Holothuroidea

Echinodermata, Deuterosome, Bilateria

Sea cucumber

Defining characteristics

• lies on one side where tube feet are used to move

• branched tenticles for deposit and suspension feeding

• Eviseration: shoot out their guts to escape predators and then regenerate them

• Pelagotheria is the exception… it can swim

Crinoidea

Echinodermata, Deuterosome, Bilateria

feather stars, sea lilies

defining characteristics

• arms have side branches with tiny tube feed that secrete mucus to capture food

• some are sedentary (sea lilies) and others can crawl (feather stars)

Five Major Groups of Echinodermata

Asteroidea, Ophiuroidea, Echinoidea, Holothuroidea, Crinoidea

Chordata

includes Urochordata, Cepaholchordata, Vertebrate

Defining Characteristics (synapomorphies- similarities within all subgroups)

• single hollow nerve chord that runs along the dorsal

• Gill or pharyngeal slits, small openings along the anterior part of the gut

• a notochord- a flexible rod that lay between verve chors and the gut

Echinodermata

Deuterostome, Bilateria

Sea Star/starfish, sea urchins

“spiny skin”

Defining Characteristics

• strictly marine and benthic

• bilaterally symmetrical larvae, pentamerous radial symmetry (five sets of body parts around a central disc) as adults

Body System

• one oral surface and one aboral (no head)

• rows of podia (tube feet) and associated with ambulacral grooves

• Endoskeletons made of calcareous ossicles from the mesodermal tissue

  • always covered by ciliated tissue

• Water Vascular System

  • water-filled canals where water enters through the madreporite

  • tube feet extended when filled with water sometimes by muscular sacs (ampullae)

Feeding

• carniverous

• everting stomach through mouth to envelope food

• short guts

• transported by coelomic food

• Urchins

  • herbivores

  • suspension and deposit feeding

Brain and Behavior

• nerve net: diffused and decentralized without cerebral ganglion

• have sensory response

Reproduction

• gonochoristic: sexes are separate

• sexual and asexual

• can asexually reproduce by fragmentation and regeneration

Deuterostomes

Bilateria

Defining Characteristics

• Early cell cleavage is radio cleavage

• the body cavity (coelom) is formed by folding of the archenteron

• blastophore become anus

Urochordata

Chordata

Defining Characteristics

Body System

• gut is U shaped

• pharynx has nermerous gills

• notochord and dorsal verve are present in larval stages

• filter feeders; water in through incurrent siphone and filtered in the pharynx, and expelled though the excurrent siphon

Behavior

• varies

• Sea Squirt: class Ascidiacea) are sessile, permanently attached, chordates

• Salps (class Thaliacea) are planktonic filter feeders

• Larvaceans (class Larvacea) are also planktonic filter feeders;

  build gelatinous houses to trap food;

  Important contributor to marine snow

Cephalochordata

Chodata

Defining Characteristics

• lack of a backbone

• brackish or estuarial environments

Body System

• Possess notochord, dorsal nerve cord, gill slits

• Ciliary-mucous suspension feeders

• water is driven into mouth and pharynx and out through pharyngeal gill slits

Vertebrata

Chordata

Defining characteristics

• have a skull (protext brain), backbone (with vertebrae), and most have jaws

Jawless Fishes

Vertebrata, Chordata

Defining Characteristics

• no jaw

Craniata

Vertabrata, Chordata

Hagfishes (no backbone no jaw)

Defining Characteristics

• Have skulls

• agnata (no jaw)

Feeding

• feed by suction

  • scavengers

Body System

• eel-like body form/no scales

• produces slime in mucus glands

  • defense mechanism

Vertabrates

Vertabrata, Chordata

Lamprey

defining characteristics

• have skull, backbone, but no jaw

• spend most of their lives as larvae buried underneath the sand

Feeding

• feed by suction

• muscular mouth with rows of teeth

Body Systems

• no scales

• eel-like body form

Gnathastomata

Vertabrata, Chordata

Defining Characteristics

• have skulls, backbones, and a jaw

Chondrichthyes

Gnathastomata, Vertebrata, Chordata

Elasmobranchii & Holocephali

Defining Characteristics

• skeleton made of cartilige (more flexible than bone)

• movable jaw with ventrally located mouths

• Placois scales rough like sandpaper

• found in all depths, mostly shallower waters

• som found in brackish water but rare

Body Shape/systems

• Fusiform (torpedo shape) for fast swimming

• Dorsoventrally compressed associated with bottom-dwelling

• move using locomotion

  • side-to-side motion to propel it forward

• rhythmic contractions are produced by myomeres (bands of muscles)

  • large pectoral fins lift while swimming

  • and heterocercal tail to lift the head up

  • liver full of oil to keep them buoyant

• have a two-chambered heart Deoxygenated blood pumped from first chamber to second chamber to gills

• Gas exchange occurs in gills

  • oxygen carried by hemoglobin in erythrocytes and is carried by arteries to capillaries to veins and back to the heart

Respritory

• Water must flow over the gills for oxygen transfer to occur

  • Some sharks are called “obligate ram ventilators”

    and must swim continuously to force water over the gills

  • Other have spiracles (an opening behind their eye)

    to pump water over their gills, or draw water in through their mouths

• Gills are supported by cartilaginous gill arches

  • has numerous gill filaments, increasing surface area and rows of thin plates (lamellae) creating high surface area

• CONCURRENT SYSTEM OF FLOW Oxygen in the water diffuses into blood along an oxygen gradient

  • Blood in gills flows in opposite direction to the flow of water over gills

• Osmoregulation- Cartilaginous fishes reduce (reverse) osmosis by increasing the amount of solutes (urea) in the blood, making salt concentration close to that of seawater

  • Amount of urea in blood is controlled by kidneys; gills block the loss of urea Cartilaginous fishes are less susceptible to urea toxicity than other vertebrates

Nervous System and Regulatory Organs

• Cartilaginous fishes also have sense organs called ampullae of Lorenzini

  that can detect weak electrical fields

  • help detect prey

Reproduction

• Fertilzation is internal- male inserts claspers into the female cloaca

• Many cartilaginous fishes are oviparous

  • Embryo enclosed in a large leathery egg case, that drops to bottom after spawning; Hatch after the parent laid the egg

  • Eggs are large, well-nourished and only a few are laid at a time

• Some cartilaginous fishes are ovoviviparous

  • the eggs develop inside the female and she gives birth to live young

• A few cartilaginous fishes are viviparous

  • the embryos absorb nutrients directly from the walls of the females reproductive trac

Feeding

• most are carnivores and have eclectic diets (take bites out of much largers prey)

• some are filter feeders

  • use gill rakers to eat plankton (planktivores)

• Food passes from mouth – pharynx – stomach – intestine – spiral valve – cloaca

  • Spiral valve of intestines increases surface area for absorption of nutrients

  • Cloaca is a common passage for digestive, excretory, and reproductive systems

Two classes of Chondrichthyes

Elasmobranchii & Holocephali

Holocephali

Chondrichthyes, Gnathastomata, Vertebrata, Chordata

Defining Characteristics

• found in deep waters/benthic

• one pair of gill slits and long rat like tain

Sharks

Chondrichthyes, Gnathastomata, Vertebrata, Chordata

Body Systems

• Fusiform body slips through water

• Heteroceral tail with upper lobe longer than lower

• two dorsal fins paired with pectoral fins

• 5 to 7 gill slits

• powerful jaws with sharp pointy teeth

  • very common to lose and regrow teeth

• variety in body plans (big/small, shape, etc)

Conservation

• Play key roles in the ecosystem as top predators and important recyclers ( i.e.,

  scavengers); loss of sharks indicates loss of ecosystem health

• negative trend in sharks

• changing the narrative of sharks

Skates and rays

Chondrichthyes, Gnathastomata, Vertebrata, Chordata

Body Systems

• dorso-ventrally flattened bodies

• head fused to limbs

• almost all benthic

Feeding

• excavating sediment

• teeth grind and crush

• filter feed mostly

Osteichthyes

Actinopterygii and Sarcopterygii

bony fishes

Actinopterygii (ray fined fishes)

Osteichthyes, Gnathastomata, Vertebrata, Chordata

Defining Characteristics

• protrusible- jaw with more freedom

  • suction feeding- the rapid opening of the mouth creates negative pressure sucking in water and food

• cycloid/ctenoid scales- thin flexible overlapping scales

• operculum (gill cover) protects the gills

• homocercal tail with lobes of tail with same size

  • lots of diversity

• fin membranes are supported by fin rays

Shape

• diverse

• fusiform= fast swimming

• dorsoventrally flattened= bottom dwellers

• Angulliforn= living among vegetation and eel shape

• elongate, triangular, round= slow swimmers

Locomotion

• undulatory movement creates force (thrust)

  • pelagic fish use mainly their tail for energy efficiency

• side force is wasted energy

• Three components of swimming: velocity, acceleration, turning

  • acceleration- strong tails, sit-and-wait predators

  • Velocity/cruisers- stiff body, mainly tail movements, and quarter moon (efficiently shaped) tails

  • Turning/manuverists- disk shape and large pectoral fins

  • Buoyancy- swim bladder to create lift using oxygen from blood

• Lateral Line- a system of sensory organs to detect movement, pressure, vibration

  • allows them to distinguish different movements from their own

Feeding

• mouth shape can illude to what they eat

  • sharp biting teeth- open ocean

  • crushing plate- sediment

  • long snouts and mouths- small prey out of crevices

  • large mouths and gill rakers- filter feeder

• mainly carnivorous

Respiratory System

• use active irrigation

  • inhale water and exhale it over the gills

• countercurrent exchange- blood and sea water running over gills move in opposite directions

  • molecules go from high to low, counter-current is more efficient

• high surface area for gas exchange

Behavior

• schooling- well-defined groupings of fish

  • selfish herd hypothesis: prey are selfishly attempting to put someone else closer to the predator

  • dilution effect: the probability of an individual gets lower the more there are

  • confusion effects: the coordinated action confuses the predator

Reproduction/Mating

• diverse reproduction habits

• ALL oviparous (lay eggs)

• male protects eggs

• practice monogamy, polygamy(one male many female),polyandry(one female many males), promiscuity (many of both)

• sequential hermaphrodism- an individual can change functional sex to another during its lifespan during its lifespan

  • Progynous-female to male

  • Protandrous- male to female

• Size advantage hyp: Why male? favor females first since rate of fitness is higher with females at the beginning, then male rate fo change increases drastically

  • larger males have higher fitness due to competition

• Why female first? opposite of why male. Female rate of change increases drastically the larger they are

• Repetitive sex change: bidirectional

  • male is dom in a certain environment so stays male. joins a new group where he is not dominant so he switched back to a female

• Simultaneous

• competition is mainly between males

• Alternative Reproductive Tactics (ARTs)

  • sneaker males- inconspicuous, sneak fertilization of eggs with type 1 male present

  • satellite males- remains on the periphery so he can immediately take opportunities to mate

  • Female mimicry- avoid detection by type 1 male to gain access to feamael

Sarcopterygii

Osteichthyes,

Defining Characteristics

• teeth with enamel

• cosmid scales- large

• fins are fleshy and has pairs

  • joined to body by one bone

• tail is diphycercal (looks like oval fin)

Reproduction

• egg develops in female = live birth

Lung Fish

• specialized respiratory system: no trachea, but lungs are connected to the larynx and pharynx

  • first lung

• omnivorous

• Activation- slows its metabolism and protein waste is converted from ammonia to produce urea

Tetrapods (reptiles and mammals)

• four-limbed vertebrate animals

• Amniotes (early reptiles)

Defining Characteristics

• waterproof skin for moisture loss

• water conserving kidney to produce urea

• costal respiration (expandin and contricticting ribs

• amniotic eggs- eggs on land that dont dry out

Reptilia

Chelonia, Squamata, Archosauria

Chelonia

Reptilia

turtles, tortoises, terrapins

Turtles

Defining Characteristics

• bodies enclosed in carapace )shell) of dermal bone

• reptilian legs are modified into flippers to help swim

• have lungs located under the carapace

• hold breath for a very long time

• global distribution

Feeding

• carnivores or omnivoreres

  • adult green sea turtles are herbivorous

Growth and survival

• Hatchlings have high mortality

• grow slowly and live long times

Reproduction

• reproduce in water

  • males pretty much stay in the sea while females deposits eggs on land

• ovoviviparous

Squamata

Reptilia

sea snakes, marine Iguana

defining characteristics

• bodies are laterally flattened and the tale is paddle shaped for swimming

• tropical Indian and pacific

• large network of branching blood vessels concentrated at the head, connecting to a single vein that goes into the brain

  • This functions to keep the brain well-oxygenated while the snake is swimming

reproduction

• mate in water

• ovoviporpus- live young

• oviparous- some lay eggs on land

Feeding

• carnivores in timent

• fixed fangs and poisonous

• smallmouth

• cooperative hunting

Marine Iguana

Defining Characteristics

• ingest seaweed/vegatarians

  • only lizard to get food from the sea

• lots of salt in the body, salt glands eject excess through sneeze

• tail is laterally flattened, undulates like a fish

Archosauria

Reptilia

saltwater crocodiles, sea birds

saltwater crocodiles

Defining Characteristics

• located in mangroves and estuaries

• aggressive marine animals

Sea birds

defining caracteristics

• have to come to shore to breath

• mature alter, live longer, and significantly fewer chicks

  • invest a lot of energy into a single egg

  • paretnal care= several months

• bread in colonies to protect from predators

Sea Birds

Penguins: Sphenisciformes, Tubenoses: Procellariformes, Pelicans and relatives: Pelecaniformes, Gulls & relatives: Charadriiformes

Penguins: Sphenisciformes

defining characteristics

• flightless

• have flippers

• southern oceans in cold, polar water

• counter current heat exchange in circulation to wings and feet

• carnivorous

  • dive for krill and small fish

• live in colonies

• monogamous pairs and lay single eggs

Tubenoses: Procellariformes

defining characteristics

• tube-like nostrils for smelling prey

• hooked bills for catching pray on the surface

• spend months/years at sea

• come on land to bread on remote places in the deep south

  • migrate to arctic to feed

• carnivores; fish, other birds, zooplankton

Pelicans and relatives: Pelecaniformes

defining characteristics

• brightly colored and ornamented

• Mainly tropical, but some species nest in Arctic and Antarctic

• Feeding is restricted to fishes

  • Cormorants dive and pursue their prey underwater

  • Frigatebirds force other birds to give up fish in mid-air (kleptoparasitism)

• guano accumulates in land which is high in N, P, and K

  • importance in contributors

Gulls & relatives: Charadriiformes

defining characteristics

• diverse

• Predators, generally feed on small fish and zooplankton