-
Phylum Nemertea aka..?
Ribbon worms
-
Characteristics of Nemertea (ribbon worms):
- Cylindrical to flattened and very long
- Most are marine, few freshwater or live in humid terrestrial habitats
- Most range from 10 to 20 cm long
- Lineus Longissius reported to reach 60 meters!
-
_______ is reported to reach lengths of 60 meters!
- Lineus Longissimus
- A type of ribbon worm
-
The ____ body plan resembles that of a flatworm.
Nemertean
-
The nemertea (ribbion worm) has some ____ with ____ lateral nerve cords.
Cephalization; 2
-
Rhynochocoel
fluid-filled sac that serves as hydraulic power sources for proboscis
-
True or false: Nemertean (ribbon worms) are gonochoric
True. aka male and female worms
-
How do ribbon worms reproduce?
- Typically sexual reproduction.
- Some asexually via fragmentation but may fragments die and do not form a new animal.
-
Phylum Annelida aka:
The Annelids
-
Characteristics of Phylum Annelida:
- Segmented worms -ringlike segments
- Brain or cerebral ganglion and sensory organs at anterior
- Many species have eyes(earthworms don't)
- Head and tail develop first then segments form between them
- segments divided by septa
- each segment has pair of excretory organs, a ganglion, and locomotory structure (marine annelid segments also have reproductive organs)
- closed circulatory system
- ventral nerve cord connects ganglia in each segment with another and the brain
-
What is the advantage of segmentation, such as in Annelids?
Development and function of individual segments or groups of segments can differ
-
Which species of annelids DO NOT have eyes?
Earthworms!
-
How do the segments in Annelids develop?
- Head and tail develop first
- Segments form between them
-
True or False: The segments found in Annelids are not divided by septa
False, they are!
-
Do annelids have an open or closed circulatory system?
Closed
-
How do annelids move?
By contracting circular and longitudinal muscles against the hydrostatic skeleton.
-
Define Chaetae (setae)
Bristles that help anchor annelids in substrates so they don't slip when they move
-
What are the two classes of Annelida?
- Class Polychaeta: Polychaetes
- Class Clitellata: Earthworms and Leeches
-
Annelid Class Polychaeta:
- Marine worms
- Parapodia-fleshy, paddle-like lateral projections used for swimming, burrowing or crawing
- Parapodia also have important role in gas exchange; in some species they are modified into gill-like structures
- Predatory polychaetes have powerful jaws
- Sedentary tube worms have feathery tentacles for filter feeding as well as gas exchange
- Most polychaetes are gonochoric and fertilization is external
- Palolo worms
- Fertilization>spiral clevage>ciliated mobile trochophore larve>growth to adult
-
Polychaetes are (freshwater/marine) worms
Marine
-
Parapodia:
Fleshy, paddle-like lateral projections used for swimming, burrowing, or crawling
-
Other than for movement, what is the other important role of parapodia?
gas exchange, some species have modified them into gill-like structures
-
Fertilization is _____ in polychaetes.
External
-
Characteristics of Palolo worms:
- Annelids: Polychaetes
- gamete-filled terminal parts considered a delicacy by some South Pacific natives
-
Class Clitellata aka:
Earthworms and Leeches
-
Earthworms were formerly in class Oligochaeta and leeches were formerly in Class Hirudinea. Why were they merged together?
Because they both have a clitellim!
-
Clitellum:
A thickened band on the body that secretes mucus to hold worms together during copulation and to form a cocoon for fertilized eggs to develop.
-
Do polychaetes have a clitellum?
No! Poly wants a clitellum.
-
Earthworm characteristics:
- Head is not well developed
- no parapodia
- few chaetae & project directly from body wall
- Eat their way through soil
- No eyes, but do have light-, chemo-, and touch-sensitive cells
- Hermaphroditic
- Cross-fertilization
- Eggs develop into young worms similar to adults
-
Leech Characteristics:
- Most are freshwater, few are marine, some live in tropical terrestrial areas
- Dorsoventrally flattened
- Hermaphroditic
- Cross-fertilization
- Clitellum only develops during mating season!
- Suckers at both ends of body
- Coelom reduced and not segmented
- no chaete (except one species)
- eat detritus or devour small animals
- some suck blood--secrete anesthetics and hirudin
-
-
Hirduo Medicainalis
medical leech
-
What do earthworms and leeches have in common?
- Both have a clitellim
- hemaphroditic
- cross-fertilization
-
What are some differences between Earthworms and leeches?
- Earthworms do not have eyes
- Leeches only develop a clitellum during mating season
- Leeches are mainly freshwater
-
Phylum Arthropoda aka:
- The Arthropods
- The most successful of all animals
- Two-thirds of all animals are arthropods
-
Great economic importance of Arthropods:
- Pollinate crops
- food for humans and other animals
- Damage to crops; insects are voracious herbivores
- Carriers or spreaders of disease to plants and animals including humans
-
Four extant plus one that is extinct (CCHMT):
- Class Chelicerata: spiders, mites, ticks, horshoe crabs
- Class Crustacea: crabs, shrimp, lobsters, barnacles, pill bugs
- Class Hexapoda: Insects
- Class Myriapoda: centipedes, millipedes
- Class Triloboita: trilobites (extinct)
-
What is the most successful of all animals?
Phylum Arhropoda
-
Arthropod key features-Mouthparts:
- Chelicera (pincers) in chelicerates
- Mandibles (biting jaws) in hexapods, crustaceans, and myriapods
-
Segmentation in Arthropods:
- Body segments look alike in some arthropods
- tagmatization: the fusion of segments into specialized functional groups
- Tagmata include: head, thorax, abdomen
- In some arthropods, head and thorax are fused to form a cephalothorax
-
Tagmatization:
- fusion of segments into specialized functional groups.
- Includes: head, thorax, abdomen
- Some arthropods: cephalothorax
-
Exoskeleton in Arthropods:
- Made of chitin and protein
- provides antagonism for muscles, support for body, protection against physical forces
- Can protect against water loss
-
The exoskeleton in arthropods is made of ____ and ___.
Chitin and protein
-
Limitation to arthropod exoskeletons include:
- Size (weight gets too great with increased size)
- Rigidity (must undergo ecdysis or molting)
-
Jointed appendages in Arthropods:
- May be modified into antennae, various kinds of mouthparts, legs
- Can bend to extend or retract
- Joints serve as fulcrum for appendage movement so leverage is possible
-
Circulatory system of Arthropods
- Open circulatory system
- Heart pumps blood anteriorly
- Blood flows towards posterior through spaces between tissues, when heart relaxes blood returns to posterior region of heart through one-way valves.
-
Nervous system of arthropods:
- Double chain of segmented ganglia along ventral surface
- three fused ganglia form brain
- functions such as eating, moving, copulation, can be carried out even when brain is removed.
- compound eyes composed of ommatidia (individual visual units)
- ocelli= simple eyes present in some arthropods
-
Ommatidia:
Individual visual units that form compond eyes in arthropods.
-
Ocelli:
Simple eyes present in some arthropods
-
Respiratory system in Arthropds:
- Gills: in marine crustaceans
- book gills: horseshoe crabs
- outer epithellium or gut for gas exchange: in some tiny arthropods
- Trachea: in terrestrial arthropods; tracheae branch into tracheoles
- Spiricles: openings in exoskeleton where air enters, can be closed to prevent water loss
- Book lungs: in many spiders
-
Book gills vs Book lungs:
- Book gills: horseshoe crabs
- Book Lungs: spiders
-
Spiracles:
openings in exoskeleton where air enters; they can be closed to prevent water loss
-
Excretory system in arthropods
- In aquatic arthropods, waste diffises from blood in gills
- Malpighian tubules occur in terrestrial insects, myriapods, and chelicerates
-
Malpighian tubules:
- Occur in terrestrial insects, myriapods, chelicerates
- slender projections from digestive tract
- attached at junction of midgut and hindgut
- tubules contain fluid, are nitro-genous wastes from blood that bathes tubules
- precipitated as uric acid or guanine that are then emptied into hindgut for elimination
- water and salts are reabsorbed by hindgut and returned to arthropod's body
- Key adaptation to life on land
-
______ in arthropods are key adaptations to life on land.
Malpighian tubules
-
Class chelicerata contains:
Spiders, mites, ticks, scorpions, daddy long-legs, horseshoe crabs
-
Chelicerate characterictis:
- Two tagmata (body sections)
- Pair of chelicera (fangs or pincers)
- Pair of pedipals
- foud pairs of walking legs
- mostly carnivorous, but mites are mostly herbivorous
-
Chelicerates have ____ tagmata. Which section bears all appendages and opisthosoma?
- Two tagmata
- The anterior prosoma bears all appendages and opisthosoma
-
Pedipalps:
- copulatory organs in male spiders
- large pincers in scorpions
- sensorial in most other chelicerates
-
Name the two orders found under Class Chelicerata:
- Order Araneae: Spiders
- Order Acari: Mites and Ticks
-
Oder Araneae:
- Spiders
- From phylum Chelicerate
- Important as predators of insects
- produce silk that is forced out of spinnerets
- all spiders have poison glads with channels through their chelicerae
- poison/venom paralyzes prey
-
Wolf spiders and tarantulas prefer to ___ than spin webs.
hunt
-
Bites from ____ and ____ can be fatal to humans and large mammals.
black widows and brown recluse
-
Order Acari:
- Mites and Ticks
- found in every habitat
- predators and parasites of various organisms
- most mites less than 1 mm long
- in mites, cephalothorax and abdomen fused into ovoid body
- Respiration using tracheae or directly through body surface
- ticks are blood-sucking parasites of humans and other animals
-
In ____ the cephalothorax and abdomen are fused together forming a ____ body.
Mites; ovoid
-
Some ticks carry disease-causing agents such as:
- Rocky Mountain spotted fever
- Lyme disease
- Red-water fever (affects cattle, horses, sheep, and dogs)
-
Crustacean Characteristics:
- Three tagmata= cephalon, thorax, and adbomen
- Two pairs of antennae (crustaceans are the only arthropods)
- Three pairs of appendages for chewing and manipulating food
- vairous pairs of legs (located on abdomen and thorax)
- Crustacean appendages are biramous("two-brached")
- large crustacean have feathery gills for respiration
- Gas exchange in smaller crustaceans occurs directly through thin regions of cuticle or through entire body
-
Which class of arthropod has two pairs of antennae?
Crutaceans
-
Crustacean reproduction:
- Gonochoric (except barnacles)
- Characteristic naupilus larva with three pairs of appendages
- nauplius is evidence for single common ancestor
-
Decapod crustaceans include:
- "Decapod" means ten feet
- shrimp, lobsters, crabs, crayfish
-
Decapod characteristics:
- five pairs of thoracic appendages
- calcium carbonate reinforced exoskeleton
- cephalothorax covered by carapace
- pincers used for obtaining food
- swimmerates on ventral surface of abdomen in lobsters and crayfish
- Uropods are paired flattened appendages at posterior that form a paddle
- Telson- tail pipe
- uropods and telson push water anteriorly, propelling animal posteriorly
-
Swimmerets:
found on the ventral surface of abdomen in lobsters and crayfish
-
Uropods:
paired flattened appendages at posterior that form a paddle
-
Telson:
Tail spine in decapods
-
____ and ___ work together to push water _____.
- Uropods and telson; anteriorly
- this propels the animal posteriorly
-
Sessile crustaceans aka...
barnacles
-
Sessile crustaceans Barnacles:
- Sessile adults, but nauplius larva is mobile
- adults are filter-feeders; sweep legs through water in order to gather small food particles
- Hermaphroditic condition is thought to be related to their sessile lifestyle
- Have the longest penis relative to their size; allows sessile animals to cross-fertilize
-
_____ have the longest penis relative to their size.
Barnacles; allows sessile animals to cross fertilize.
-
Arthopod Class: Hexapoda aka?
- The Insects
- largest group of animals in terms of number of species and number of individuals
- found in every habitat on land and in freshwater; few found in the sea
-
External characteristics of insects:
- Digestive tract is tube about same length as body in many
- digestion occurs in stomach or midgut
- Malpighian tubules for excretion
- trachea for gas exchange
- spiracles are openings between segments along side of abdomen and thorax where air enters
-
In insects that feed on juices, digestive system is ____ and may be several times longer than body.
coiled
-
Sensory receptors of insects:
- Eyes
- Sensory setae sensative to mechanical and chemical stimuli; numerous on antennae and legs
- tympanum: thin membrane that acts like eardrum, detects sound waves and vibrations
- pheromones are chemicals released by insects for communicating mating signals, trail markers, etc.
-
Insect life histories:
- Metamorphosis: change in form
- simple metamorphosis: eggs>nymph stages>adult
- Complete metamorphosis: egg>larva>pupa(chrysalis)>final molt into adult or imago.
-
What is the difference between simple and complete metamorphosis?
Complete metamorphosis includes a pupa(chrysalis) stage.
-
Class myriapoda includes:
Centipedes and Millipedes
-
Class Myriapoda characteristics:
- Both have head followed by numerous segments
- both are gonochoric
- fertilization is internal
- all lay eggs
-
Subclass Chilopoda:
- Centipedes
- One pair of legs per segment
- some centipedes hatch with a final number of legs; others add legs after hatching
- carnivorous
- poison fangs
-
Centipedes that do not add legs tend to do what?
Tend to care for their young, a rather uncommon behavior among invertebrates
-
Subclass Diplopoda:
- Millipedes
- two pairs of legs per segment
- Herbivorous
- roll into flat coil or sphere for defense
- glands produce foul-smelling fluid
- some produce cyanide gas
-
This type of myriapod can produce cyanide gas
Millipedes
-
Which is the poisonous type of myriapod?
The centipede
-
Centipedes are (carnivorous/herbivorous) but Millipedes are (carnivorous/herbivorous).
- Centipedes: carnivorous
- Millipedes: herbivorous
-
Phylum Echinodermata: The Echinoderms
- "Spiney skin"
- Exclusively marine
- Deuterostome development (only other phylum beside vertebrates)
- Endoskeleton of calcium carbonate plates
- Pentaradial symmetry (parts of 5)
- water-vascular system aids in movement and feeding
- larva have bilateral symmetry
-
What is different about echinoderm larvae?
- Echioderms have pentaradial symmetry but larvae is bilateral
- thought to have evolved from bilaterally symmetrical ancestors.
-
The oral surface of asteroids (star like), ophiiroids (snake like), and echinoids (spike like) face (away/towards) subrtrate.
Towards the substrate
-
The oral surface of crinoids(sea lillies) faces (towards/away) from substrate.
Away from substrate
-
Holothuroids aka?
Sea cucumbers
-
Holothuroids have a ______ axis and oral surface that faces _____.
- horizontal axis
- surface faces forward
-
Echinoderm exoskeletons:
- Ossicles = calcium carbonate plates that make up endoskeleton
- Depending on the class, ossicles may be more loosely arranged, tightly fit together to form a test, or scattered throughout the body.
- mutable callagenous tissue can change texture from tough and rubbery to fluid in seconds if animal is disturbed.
-
Echinoderms can automize body parts. This means they can?
Cast off body parts
-
Echinoderm Water-Vascular System (WVS)
- Radially organized
- Madreporite
- WVS extends out into each arm of a sea star
- Ampulla allows tube foot to extend or contract
- gas exchange occurs across body surface and the tube feet.
-
Holothuroidans (sea cucumbers) also have respiratory tree that branch off the hindgut, this means?
water enters through the anus
-
Madreporite:
Structure on aboral(away from the mouth) surface where water enters Echinoderms
-
Ampulla:
The bulb that allows tube feet in echinoderms to extend or contract
-
Echinoderm regeneration and reproduction:
- Many echinoderms can regenerate body parts
- Sexual reproduction is the norm
- gonochoric
- fertilization is external
- larvae are bilateral
- Each class of echinoderm has a characteristic larva
-
These echinoderms can automize their arms
Asteroids and ophiuroids
-
These echinoderms can eviscerate their digestive system entirely
Holothuroidians (sea cucumber)
-
True or false: Some echinoderms can reproduce asexually by splitting
True
-
What are the 5 extant classes of echinodems (ACHOE)?
- Asteroidea
- Ophiroidea
- Echinoidea
- Holothuroidea
- Crinidea
-
Class Asteroidea:
- Sea Stars
- Orginized in parts of five or multiples of five
- predators
-
Class Ophiuroidea:
- Brittle stars
- Arms are slender and "snake-like"
- Arms join central disk very abruptly
- tube feet for feeding not locomotion
- brittle stars have no anus
-
Class echinoidea:
- Sea urchins and sand dollars
- no arms
- five double rows of tube feet extend through calcareous test (shell)
- Spines are moveable and have a ball-and-socket joint
-
Class Holothuroidea
- Sea Cucumbers
- Oriented horizontally to substrate
- Parts of five
- Filter feeders
- Have repiratory tree
- If skin is rubbed, can go from rigit to liquid in a couple minutes
-
Class crinoidea:
- Sea lilies and feather stars
- oral surface faces up
- filter feeders
-
What class of Echinoderm has no anus?
Ophiuroidea: Brittle Stars
-
Which class of echinoderm has movable spines with a ball-and-socket joint?
Class Echinoidea: sea urchins and sand dollars
|
|