Chapter 11 Flashcards
The layer of the mesoderm that lines the body wall and forms the septa is called the
peritoneum
The polychaetes differ from other annelids by having a well-developed head that often bears the eyes, antennae, and sensory palps, and is called a ________, or first segment
prostomium
The paddlelike appendages that characterize the polychaetes are called
parapodia
The segment of the annelids that bears the jaws is called the
peristomium
Some polycheates live most of the year as sexually unripe animals called _____ and the segments that break off and contain gametes are called the ________.
atoke, epitoke.
Food is drawn into the mouth of an oligochaete by suction created by the muscular
pharynx
The annelids have a double circulation in that materials can be moved by the blood or by the
coelomic fluid.
Leeches feed from the body fluids of their prey. The ones that feed on blood have very slow digestion. This is workable because they have ________ to aid in digestion.
bacteria
The hirudineans
usually lack setae.
The coelom of the annelids is formed by splitting of the embryonic mesoderm on each side of the gut within each compartment. For this reason the cavity is sometimes called a
schizocoel.
Locomotion in the annelids is accomplished by alternating waves of contraction by the longitudinal and circular muscles passing down the body. This is known as
peristaltic contraction.
The polychaetes differ from other annelids by having a well-developed _________ with specialized sense organs, and paired paddlelike _________.
head, parapodia
The type of tissue that is found around the intestine in the annelids that can synthesize glycogen and break free to distribute nutrients in the coelom is called
chloragogen tissue.
True or false?
The structure seen in oligochaetes, which secretes mucus and produces a cocoon that protects the developing young zygote is called the clitellum.
true
True or false?
The hirudineans have 34 segments, anterior and posterior suckers, and no parapodia.
true
True or false?
A nephridium occupies two segments and is composed of a ciliated funnel called a nephrostome, and several loops of tubules that lead to an opening called a metanephridium.
false
True or false?
Unlike the polychaetes, the oligochaetes are characterized by having a clitellum for reproduction and suction for feeding.
true
True or false?
The oligochaetes have a nephrostome in each segment, and a nephridiopore in the next segment to facilitate excretion.
true
True or false?
The rigid chitinous structures in annelids that allow the fleshy parapodia to form attachments to the substrate are known as the spines.
false
True or false?
The body cavity of an annelid is referred to as a pseudocoelom.
false
True or false?
The first segment of an annelid, which bears the mouth, is called the prostomium.
false
True or false?
A ventral heart propels the circulatory fluid of the annelid.
false
True or false?
The body cavity of annelids is filled with fluid and serves as a hydrostatic skeleton in all classes.
false
True or false?
Copulation in oligochaetes is facilitated by the clitellum, which secretes the gametes.
false
True or false?
Leeches are all ectoparasites, whereas all oligochaetes are freeliving.
false
True or false? In a cladogram of the phylum Annelida, the most primitive group would be the class Hirudinea.
false
True or false?
The peristomium is the lining of the coelom.
false
True or false?
The oligochaetes feed by suction. This is accomplished by expanding the prostomium.
false
True or false?
The organ of excretion in annelids is the nephridia.
true
True or false?
The ciliated part of the organ of excretion in an annelid is the nephrostome.
true
True or false?
The polychaetes have a larval form that is the trochophore.
true
True or false?
Development in the oligochaetes and the hirudineans is direct, and therefore no larva is formed.
true
True or false?
The term metamerism means that the organism has internal septa.
false
The siboglonids derive most of their energy from chemoautotrophic bacteria located in the _____.
trophosome
The most important structural characteristic that appears first in the Annelids is ____, division of the body into similar segments.
metamerism
The annelid typhlosole increases digestive efficiency by ______.
increasing surface area for absorption
The Oligochaeta and _____ together form the clade Clitelleta.
Hirudinea
Members of phylum Sipuncula are considered to be ________ feeders and are found in
deposit, marine habitats.
Members of the former phylum Echiura are considered to be ________ feeders and are found in
deposit, marine habitats.
The members of the Echiura are distinguished from the other phyla in this chapter by having
a heart and closed circulatory system.
The members of phylum Sipuncula are distinguished from the other phyla in this group by having
an introvert.
True or false?
The sipunculids possess several unique characteristics, including the introvert and the trophosome.
false
True or false?
The anus in sipunculids is actually located near the oral area, which makes sense, as they live buried in the bottom sediments with only the anterior end exposed.
true
True or false?
If you had a parasitic worm make its presence known by sticking out of your nose (yuk!), you might surmise that you had an infection of sipunculids.
false
