Annelida Flashcards
The layer of the mesoderm that lines the body wall and forms the septa is called the A) mesentery. B) parapodium. C) peritoneum. D) odontophore.
C) Peritoneum
The paddlelike appendages that characterize the Errantia are called A) propodia. B) peripodia. C) parapodia. D) setae.
C) Parapodia
The hirudineans Usually lack setae. True or False
True
a stiff structure resembling a hair or a bristle, especially in an invertebrate is called…….
Setae
The structure seen in some Sedentaria, which secretes mucus and produces a cocoon that protects the developing young zygote, is called the …..
Clitellum
The hirudineans have 34 segments, anterior and posterior suckers, and no parapodia. True or False
True
The body cavity of an annelid is referred to as a pseudocoelom. True or False
False. It is a Coelom
The first segment of an annelid, which bears the mouth, is called the prostomium. True or False
True.
The organ of excretion in annelids is the…..
Nephridium
Development in the hirudines is direct, and therefore no larva is formed. True or False
True
The order Clitelleta is located within the class: A) Errantia B) Sedentaria C) Onychophora D) Hirudinea
B) Sedantaria
What is the basic Phylogeny of Annelids
True tissue -> Bilaterally symmetrical -> Protostome development -> Lophotorochozoa -> Segmented coelom present
What are the major external features of an Annelid
Metamerism - Prostomium - Pygidium - Bilaterally symmetrical with head - Moist cuticle - Paired parapodia/Setae
Define Metamerism
Segmented body
Define Prostomium
Head - contains brains
Define Pygidium
Carries anus - Regenerates new body parts
What are the parapodia/setae used for
Used for mobility and also staying stationary
What are common feeding habitats
Herbivorers - Omnivorers - Predator
Liner unsegmented gut - Mouth and anus - Reversible pharynx - Sedentaria have muscular gizzard
Hirudines have grasping teeth
Describe an Annelids skeleton and locomotion
Hydrostatic skeleton via coelom. Longitudinal muscles (Inner) and Circulatory muscles (Outer)
Describe the respiratory/circulatory system of an Annelid
Permeable body covering - Closed circulatory system - Dorsal vessels carrie blood anterioly - Ventral vessels carries blood posteroily - Lateral vessels link them + work as 5 large hearts
How do Annelids deal with waste excretion.
Paired nephridia in each segment/Some Ammonia across body surfaces
Describe the basic Annelid nervous system
Anterior brain with a solid ventral nerve cord
Light/Chemical/Touch/Vibration Receptors across the whole body
What is the function of the Hormeno system
To stimulate gonads in order to regrow them
How does each family with in Annelid reproduce?
Errantia/Setentaria are Dioecious (Can be asexually)
Clitellate (Distinctive Gonads)/Hirudinidae (Internal) are hermaphroditic
What are Errantia’s characteristics
Distinct head with Sense organs/Chitinous jaws - Parapodia/setae for locomotion/burrowing/Respiration - No permanent gonads - Gametes arise via swelling in Peritoneum. External fertilisation
Define the Peritoneum
Membranes that line the cavity of the abdomen
What are Hirudineas major characteristics
No Parapodia/Setae/sensory appendages (Has eyes) - Posterior/oral suckers - Hermaphroditic (Clitellum) - Carnivorous
Define the Clitellum
Area for the reproductive organs
What are the general reproductive features of Hirudineas?
Typically have ventrally opening Gonopores/ Or just a penis and vagina - Internal fertilisation via Spermatophore or Hypodermic implantation.
Young develop in Coccoons
Define Gonopore
Genital pore
Define spermatophore
A protein capsule containing a mass of spermatozoa
Briefly describe the CNS of a Hirudinea
Large Neurons in a single layer in 32 segments, each with a ganglion/repeats for each segments
