Segmented worms - Annelids Flashcards
The phylum Annelida refers to what kind of worms?
Segmented worms
What is septa?
Thin membranes
FITB: ______ divide earthworms into segments, more properly called metameres
Septa
T/F: Segmented worms have repeated structures throughout the body
True
Can there be differentiation in structure when it comes to segmented worms?
Yes, although most are fairly similar
T/F: There is a lot of differentiation of between each individual segment
False
What kind of symmetry do Annelids have?
Bilateral symmetry
FITB: Annelids have _________ skeletons for movement & support
Hydrostatic
T/F: Annelids are cephalized, but only internally
True
T/F: Annelids do not have a complete digestive tract
False
What kind of body plan do Annelids have? (It’s a phrase)
“Tube-within-a-tube”
T/F: A gas exchange system can be found in segmented worms
False
How do Annelids differ from Nematodes body wise? (Hint: muscles)
Annelids have longitudinal and circular muscles in the body wall & the digestive system
T/F: The presence of Longitudinal and circular muscles in Annelids allows for peristaltic movements of the gut and body to occur
True
FITB: Annelids have a more complex ___________ system than Nematodes
Excretory
What is the nephridium?
An organ that functions like a kidney
T/F: There are paired nephridia in each metamere segment
True
T/F: Annelids have a true circulatory system that consists of a closed circuit of arteries, capillaries & veins
True
What is the correct term for the body part ‘hearts’ in Annelids?
Aortic arches
T/F: Annelids only have one aortic arch
False; they have multiple
What is the function of aortic arches?
To regulate blood pressure
FITB: Pumping is done by the _________ _____ _______
Muscular Dorsal Vessel
What is an example of a respiratory pigment seen in many species?
Hemoglobin
T/F: Segmented worms have a respiratory system
False
T/F: Some types of marine and freshwater annelid forms have external respiratory structures (gills) that increase surface area for diffusion
False; Only marine forms have these structures which allow for increased surface areas for diffusion
FITB: Respiration in all annelids is by ________ across the ___________ between blood vessels and outer environment
- Diffusion
- Epithelium
In the _________ system, annelids have a ________ nerve cord connected to a _________ located “brain” via two circumpharyngeal connectives
- Nervous
- Ventral
- Dorsally
What is a pharynx?
The gut
What is the more proper term to describe the brains of annelids?
Cerebral ganglia
T/F: Each metamere (segment) has a pair of fused ganglia
True
What are chlorogogue cells?
Modified cells of the peritoneum which covers the digestive system
What are the 2 main functions of chlorogogue cells?
- Converting waste products of protein metabolism into ammonia and or urea
- Synthesizing glycogen and fat from excess glucose
FITB: Glycogen is a ________ energy-term storage substance that is carried out in your ________
- Medium
- Cells
What are the 3 Annelid classes?
- Oligochaeta
- Polychaeta
- Hirudinea
What are setae (aka “chaetae”)?
Bristle-like structures that protrude from the skin
T/F: Setae can be short and rigid or hair-like and flexible
True
What is an example of a species that is part of the Annelid Setae type?
Sea mouse
Sea mice are part of which class of Annelids?
A. Oligochaeta
B. Polychaeta
C. Hirudinea
Polychaeta
TOT & FITB: The Oligochaeta class has relatively few/lots of setae made of _______
- Few
- Chitin
T/F: Setae can range to be small, stout or long and flexible
True
FITB: Roughly half of the ~3,500 species of Oligochaetes are _________
Earthworms
FITB: Other types of Oligochaetes are smaller, _______ species
Aquatic
T/F: Some species of Oligochaetes can be microscopic in size
True
The Earthworm digestive system mainly consists of what 6 body parts?
- Mouth
- Pharynx
- Esophagus
- Crop (for storage)
- Gizzard
- Gut
Are Earthworms monoecious or dioecious?
Monoecious
What kind of sexual reproduction occurs with Earthworms?
Cross-fertilization that involves sperm exchange
FITB: The male reproductive part is called a _______ vesicle that is a storage place for sperm before copulation occurs
Seminal
FITB: The female reproductive part is called a seminal __________ which is the place where sperm is stored after copulation occurs
Receptacle
FITB: After fertilization occurs, an egg lays in a _______
Cocoon
MC & FITB: Most Oligochaetes are…
A. Herbivores
B. Carnivores
C. Detritivores
that play a role in the recycling of _______ in the ecosystem
- C
- Nutrients
T/F: All earthworms in our area are of native origin and do not reduce native plant diversity
False; they are exotic and they do reduce native plant diversity
Detritivores eat what? (List 3 examples)
- Dead plants
- Leaves
- Organic matter
FITB: The class Polychaeta are ______ annelids with many _______ of various forms
- Marine
- Setae
What is meant when we say that Polychaeta are “errant species”?
They are wandering predators
What are 2 examples of an errant specie?
- Sandworm
- Clamworm
Why do predatory species have pronounced external cephalization?
Because they are wandering predators looking for prey
FITB: Many other types of Polychaeta annelids are ______-dwelling filter or ________ feeders
- Tube
- Deposit
MR: Nereis, a type of Polychaeta have what type of body structure that is used for gripping?
Parapodia
T/F: Parapodia are paired, muscular extensions of each somite (segment) with setae that is used for locomotion or anchoring in a burrow
True
TOT: Polychaeta are monoecious/dioecious
Dioecious
T/F: Polychaeta have permanent gametes
False
MC: What kind of development does Polychaeta have?
A. Direct
B. Indirect
C. Unobservable
B. Indirect
What is the name of the larva that can swim?
The Trochophore larva
FITB: Epitoky is a form of ____________
Reproduction
T/F: Benthic worms can asexually bud off sexually mature individuals that can swim
True
The class Hirudinea consists of what kind of Annelid specie?
Leeches
What are is a very identifiable body part on a leech?
- Anterior sucker with mouth
The posterior sucker on a leech serves for what 2 functions?
- Attachment
- Movement
FITB: About 75% of species are _____________ (hint: fancy word for bloodsuckers) of vertebrates while the rest are predators of invertebrates
Ectoparasites
What organism do leeches like to hunt?
Snails
What are 2 things that leeches do not have in comparison to other annelids?
- Setae
- Internal septa
T/F: The coelom of Hirudinea is very reduced, mostly connective and contains chlorogogue tissue instead
True
T/F: The circulatory system in Hirudinea is not reduced
False
T/F: Remnant coelom can form channels that act as vessels in leeches
True
T/F: The digestive system is modified for fluid feeding in hematophagous species
True
FITB: Hirudinea are _________ with ________ ___________
- Monoecious
- Direct development
Does Hirudinea have a larval stage?
No
T/F: There are 4-13 pairs of testes present in Hirudinea
False; 4-12 pairs of testes
T/F: Hirudinea have a pair of ovaries present
True
The “little packet of sperm” is known more commonly as what?
A spermatophore
FITB: Sperm gets transferred into a a __________ by a ____ or by hypodermic _______________
- Spermatophore
- Penis
- Impregnation
FITB: Hirudo medicinalis has historically been used for _____-_______, in the belief that this would cure disease
Blood-letting
T/F: Leeches can aid in the process of relieving congestion in the vicinity of a wound
True
T/F: There are such things known as leech farms that exist
True
