Lab 6 Annelida - EVERYTHING
Select one from the options the correct order in which food passes in the earthworm: intestine, esophagus, gizzard, anus, pharynx, mouth, crop. a) (1) Mouth, (2) esophagus, (3) crop, (4) pharynx, (5) gizzard, (6) intestine, (7) anus b) (1) Mouth, (2) pharynx, (3) esophagus, (4) crop, (5) gizzard, (6) intestine, (7) anus c) (1) Mouth, (2) esophagus, (3) pharynx, (4) crop, (5) gizzard, (6) intestine, (7) anus
(1) Mouth, (2) pharynx, (3) esophagus, (4) crop, (5) gizzard, (6) intestine, (7) anus
Phylum Annelida Class Clitellata Subclass Oligochaeta Features
(earthworms) Some aquatic and marine Few setae (on ventral/belly surface) Complete septa Specialized gastrointestinal system: esophagus, crop, gizzard, intestine Clitellum secretes mucus sheath for egg
Phylum Annelida Class Clitellata Subclass Hirudinea Features
(leeches) Ectoparasites No setae No internal septa, but do annuli Inch-worm movement Two suckers - Small anterior sucker - with mouth for attachment and feeding - Large posterior sucker- mainly locomotion, but also attachment
Phylum Annelida Class Polychaeta Features
(sandworms, marine worms) Mostly marine Incomplete septa Parapodia (feet-like) with lots of setae (bristles) - Aid in locomotion and increase surface area for gas exchange - With Acicula that provide support to parapodia and setae
Movement/locomotion via Inner longitudinal and outer circular
- Setae - Polychaeta: long setae and parapodia - Oligochaeta: short and few setae - Hirudinea: no seta, use suckers to "inch worm
SKELETON/SUPPORT:List the structures or ways this group of animals support themselves (e.g. hydrostatic skeleton, exoskeleton, etc.). A)Hydrostatic skeleton B)Endoskeleton C)Exoskeleton like a shell
A)Hydrostatic skeleton
Do Hirudinea possess setae? (yes or no)
No
ectoparasites with suckers for feeding; lack setae and parapodia
Subclass Hirudinea
leeches
Subclass Hirudinea
common earthworm
Subclass Oligochaeta
free-living freshwater or terrestrial worms with setae
Subclass Oligochaeta
Septa
Thin layers of tissue. Organs pass through these internally separate metameres
Why must terrestrial annelids such as earthworms maintain a moist skin surface?
To allow gas exchange to occur across the epidermis
circulatory system (aortic arches)
To what system does the structure indicated by line C belong ?
Phylum Annelida Class Clitellata Subclass Hirudinea Locomotion
inch-worm movement large posterior sucker
Major distinguishing features of Annelida are:
1. Eucoelomates 2. Metamerism 3. closed circulatory system 4. complete digestive tract
CIRCULATION:Describe the circulatory system (e.g. diffusion, open system, etc.). A)Aortic arches B)Open circulatory system C)Closed circulatory system D)3-chamber heart E)4-Chamber heart F)No circulation at all
A)Aortic arches C)Closed circulatory system
RESPIRATION:Describe how the group respires (e.g. diffusion, book lungs, gills, etc.). A)Diffusion B)Book lungs C) Lungs D)Gills inside mantle E)Gils outside the mantle F)Vascularized tissue lining the mantle cavity
A)Diffusion
CLASSIFICATION: Only answer the phyla, classes, subclasses and other classification that you are responsible for knowing this week for Lab 6 A)Phylum Annelida B)Phylum Mollusca C)Phylum Nematoda D)Platyhelminthes E)Class Hirudinea
A)Phylum Annelida
MOVEMENT/LOCOMOTION:What structures are used to help them move around their environment?(e.g. types of muscles, jointed legs, cilia, etc.). A)Setae B)Cilia C)Longitudinal muscles only D)Circular muscles only E)Both longitudinal and circular muscles F)Flagella G)Hydrostatic skeleton
A)Setae E)Both longitudinal and circular muscles G)Hydrostatic skeleton Movement/locomotion via Inner longitudinal and outer circular - Setae - Polychaeta: long setae and parapodia - Oligochaeta: short and few setae - Hirudinea: no seta, use suckers to "inch worm
REPRODUCTION:Describe the types of reproduction that occur in the group (e.g. sexual vs. asexual) and any other characteristics or specializations they may have for reproducing (e.g. monoecious vs. dioecious, fission, budding, etc.). A)Sexual B)Monoecious only C)Dioecious only D) Both monoecious and dioecious E) Some alternation of sexual and asexual stage F) Clitellum
A)Sexual D) Both monoecious and dioecious F) Clitellum
Compare Annelida segmentation to Cestoda segmentation
Annelida segments are different segments within the same individual whereas Cestoda's segments (proglottids) are essentially their own entity
DIGESTION/FEEDING:Describe the digestive process (e.g. incomplete and extracellular) and any specializations for feeding (e.g. cnidocytes, tentacles, etc.). A) Incomplete gut / gastrovascular cavity B) Mouth & Anus C) Crop & gizzard D)Filter feeder E)Predators F)Endoparasites G)Ectoparasites H)Suspension feeders I)Free living J)Deposit feeding K)All of the above except A
B) Mouth & Anus C) Crop & gizzard D)Filter feeder E)Predators F)Endoparasites G)Ectoparasites H)Suspension feeders I)Free living J)Deposit feeding Some Polychaeta, are filter feeders and suspension feeders and feed on suspended particles. Hirudinea are ectoparasites
ORGANIZATION:At what level is the basic body plan organized? (e.g. cell, tissue, organ, etc.) A)Tissue level B) Organ level C)none of the above
B) Organ level
EMBRYONIC DEVELOPMENT:List the characteristics found during the formation of the blastula (e.g. triploblastic, deuterostome, etc.). A) Diploblast B)Triploblast C)Protostome D)Deuterostome E)Acoelomate F)Pseudocoelomate G)Eucoelomate (or coelomate) H)No embryonic development
B)Triploblast C)Protostome G)Eucoelomate (or coelomate)
SENSORY/NERVOUS:Describe the nervous system (i.e. ganglia, CNS, ventral nerve cord, etc.) and any sensory specializations found in the group (e.g. auricles, eyes, antennae, etc.). A)Nerve net only B)Complex compound eyes C)Cerebral ganglia D)Ventral nerve cord only E)Dorsal nerve cord only F)Cephalization
C)Cerebral ganglia D)Ventral nerve cord only F)Cephalization
What type of nervous system do annelids have?
Cerebral ganglion - "brain" like Ventral nerve cord
marine worms with parapodia
Class Polychaeta
sandworms
Class Polychaeta
Phylum Annelida Class and Subclasses to Know
Class Polychaeta Class Clitellata - Subclass Oligochaeta - Subclass Hirudinea
Do annelids have a complete or incomplete gut?
Complete gut -> mouth and anus
Phylum Annelida Class Clitellata Subclass Oligochaeta Incomplete or Complete Septa?
Complete septa
Phylum Annelida Class Clitellata Subclass Hirudinea Setae
Completely lack setae (bristles) No internal septa (internal seperation), but do have annuli (external rings)
SYMMETRY:What type of symmetry is found in the basic body plan? (e.g. asymmetrical, radial. etc.) A)Asymmetry B)Radial symmetry C)Pentaradial symmetry D)Bilateral symmetry
D)Bilateral symmetry
EXCRETORY/OSMOREGULATION:List how the group eliminates waste from their systems (e.g. diffusion, nephridia, Renette cells, Malpighian tubules etc.). A)Diffusion B)Protonephridia = Flame cell ONLY C)Metanephridia ONLY D)Nephridia: both Protonephridia & Metanephridia E)Malpighian tubules F)Kidneys
D)Nephridia: both Protonephridia & Metanephridia
Online Lab Phylum Annelida Class Clitellata Subclass Oligchaeta Preserved Specimens
Earthworms are found in the soil everywhere except in deserts. They construct burrows by swallowing soil. Earthworms have beneficial effects on the soil by increasing drainage, aeration and mixing layers.
Phylum Annelida Class Clitellata Subclass Hirudinea Ecto- or Endoparasites?
Ectoparasites
Phylum Annelida Class Clitellata Subclass Oligochaeta Setae
Few (not that many setae)
Phylum Annelida Subclass Oligochaeta
Identify the phylum and subclass of the specimen depicted.
gizzard
Identify the structure by line B.
parapodium
Identify the structure indicated by E.
longitudinal muscles
Identify the structure indicated by line A.
ventral nerve cord
Identify the structure indicated by line B.
circular muscles
Identify the structure indicated by line C.
acicula
Identify the structure indicated by lines D.
Reproduction Direct vs. Indirect development
Indirect = larval stage Direct = adult like babies Larvae in polychaete are trochophore (free-swimming) since most are marine and it makes sense evolutionarily that they have a swimming larvae
Locomotion in Free-Moving Polychaetes
Locomotion in free-moving polychaetes is accomplished by circular, longitudinal, and parapodial muscles and by coelomic fluid. Body undulations, which help the worm to move rapidly, are produced by the contraction of longitudinal muscles stimulated by the backward stroke of parapodium of a particular segment.
Phylum Annelida Reproduction Class Clitellata Subclass Oligochaeta
Monoecious Direct development Clitellum
Phylum Annelida Reproduction Class Clitellata Subclass Hirudinea
Monoecious Direct development Clitellum when reproductive
Phylum Annelida Reproduction Class Polychaeta
Most monoecious (some dioecious) Indirect development (trochophore larva) No clitellum
Phylum Annelida Class Clitellata Subclass Oligochaeta Name Meaning
Oligo = "few" Chaeta = "hairs"
Phylum Annelida Class Clitellata Subclass Oligochaeta Location of Setae
On ventral (belly) surface
What type of organization do organisms in Phylum Annelids have?
Organ level
Phylum Annelida Class Polychaeta Parapodia and Setae
Parapodia (feet-like) with lots of setae (bristles) - Aid in locomotion and increase surface area for gas exchange - With Acicula provide support to parapodia and setae
What phylum does this organism belong to?
Phylum Annelida
Online Lab Phylum Annelida Class Polychaeta Parapodia
Polychaetes have distinctive parapodia, which have multiple functions in different polychaetes. Most importantly, they are used for locomotion and increase the surface area available for gas exchange. They have hair-like setae that are used for gripping the substrate. Larger internal acicula form a skeletal support for the attachment of muscles.
Phylum Annelida Class Clitellata Subclass Oligochaeta Gatrointestinal System
Specialized gastrointestinal system: esophagus, crop, gizzard, intestine
True or False? All adult annelids are vermiform
True
Phylum Annelida Class Clitellata Subclass Hirudinea Suckers
Two suckers - Small anterior sucker - with mouth for attachment and feeding - Large posterior sucker- mainly locomotion, but also attachment
Reproduction (store sperm until needed to fertilize eggs)
What is the function of the structure indicated by line A?
Are Annelids metameric?
Yes
Which of these are major distinguishing features of Annelida? a) Eucoelom b) Metamerism c) Open circulatory system d) Incomplete digestive tract
a) Eucoelom b) Metamerism
Which of the following is a trait that Platyhelminthes and Annelida share that is not found in Cnidaria? a) Triploblastic development b) Complete digestive tract c) Coelom
a) Triploblastic development
What anatomical similarities do you see among leeches, earthworms, and sandworms? a) complete digestive system, repeated internal structures (nephridia, reproductive structures, hearts, etc.) b) presence of setae c) presence of a clitellum
a) complete digestive system, repeated internal structures (nephridia, reproductive structures, hearts, etc.)
What features of Polychaeta would lead you to believe that they are free-living predators? a) sensory structures on the head b) parapodia used in locomotion c) no structures for attaching to host d) fangs for capturing and subduing prey
a) sensory structures on the head b) parapodia used in locomotion c) no structures for attaching to host d) fangs for capturing and subduing prey
How do Hirudinea move? a) they move using the anterior and posterior suckers to attach to the substrate and loop their bodies along like inchworms b) they swim when in water c) they use their setae
a) they move using the anterior and posterior suckers to attach to the substrate and loop their bodies along like inchworms b) they swim when in water
Phylum Annelida segmentation
annellus = "little ring" Segmented Metamerism - body segments with repeating organs - Homonymous - segments more less the same - Heteronomous - metameres different
Body undulations, which help the Polychaeta worms move rapidly, are produced by what muscles (if any ) ? a) muscles involved are only longitudinal like all other worm-like organism b) produced by the contraction of longitudinal muscles stimulated by the backward stroke of parapodium of a particular segment. c) accomplished by circular, longitudinal, and parapodial muscles and by coelomic fluid
b) produced by the contraction of longitudinal muscles stimulated by the backward stroke of parapodium of a particular segment. c) accomplished by circular, longitudinal, and parapodial muscles and by coelomic fluid
What type of symmetry do annelids have?
bilateral
What is metamerism and which phylum is characterized by it?
body segments with repeating organs Phylum Annelida
Circulatory System in Annelids
closed circulatory system - contractile vessels (heart)
Are Annelids coelomate, acoelomate, or pseudocoelomate?
coelomate
Respiration in Annelids
diffusion
Phylum Annelida Class Clitellata Subclass Oligochaeta Common Name
earthworms
Hirudinea
ectoparasites
Digestive System Class Polychaeta
eversible pharynx, esophagus, esophageal caeca, jaws
Polychaeta
filter feeders and suspension feeders and feed on suspended particles.
What type of skeleton do annelids have?
hydrostatic skeleton - cuticle Polychaeta have acicula
Phylum Annelida Class Polychaeta Incomplete or complete septa?
incomplete septa
Movement/locomotion in Annelids
inner longitudinal and outer circular muscles - setae
Phylum Annelida Class Clitellata Subclass Hirudinea Common Name
leeches
Movement/locomotion Class Polychaeta
long setae and parapodia
Metamerism Heteronomous
metameres (segments) different
Phylum Annelida Class Polychaeta Habitat
mostly marine
Digestive System Subclass Oligochaeta
muscular pharynx, esophagus, gizzard, typhlosole
Excretion/osmoregulation in Annelids
nephridia
Movement/locomotion Subclass Hirudinea
no seta, use suckers to "inch worm"
Annuli
outer rings that separate metameres **external evidence of septa**
Phylum Annelida Class Polychaeta Name Meaning
poly- = "many" chaeta = "bristle"
Are Annelids protostomes or deuterostomes?
protostomes
Phylum Annelida Class Polychaeta Common Names
sandworms and marine worms
Phylum Annelida Class Clitellata Subclass Oligochaeta Clitellum
secretes mucus sheath for egg thick band on body
Metamerism Homonymous
segments more or less the same
Movement/locomotion Subclass Oligochaeta
short and few setae
vermiform
soft-bodied, circular in cross-section, and longer than they are wide
Phylum Annelida Class Clitellata Subclass Oligochaeta Habitat
some aquatic and marine
What's the function of the acicula in Polychaetes?
structural support for the setae and parapodia
Phylum Annelida Class Polychaeta Acicula
thick black lines provide support to parapodia and setae
Are Annelids diploblastic or triploblastic?
triploblastic
