This is followed by 21 midbody segments, which include 21 neuronal ganglia, two reproductive organs, and 9 pairs of testes. The leech also has 32 brains because a brain segment is located in each segmentation of the body. The segments of the body are very smooth. Leeches have a small sucker at the anterior end and a large sucker at the posterior end. The body of the leeches is segmented according to the functionality of each segment. Buffalo leech were collected. The Leech hirudinia. The body of leech has: (a) 23 segments (b) 33 segments (c) 38 segments (d) 30 segments Answer: (b) 33 segments. (10)The anterior Sucker is oval and cup-shaped, with its hollow towards the ventral surface. Mammals are animals. Leeches get their energy from sucking blood, and because of this, they have been used over the years for medicinal purposes. Recognise the structural features of different organ systems. The anterior end of leech has a lobe-like structure called anterior sucker. This basic body plan has two variations: the stationary polyp and the floating medusa (Figure 17.10). Finally, the last seven segments are fused to form the animal's tail sucker, as well as its posterior brain. 2. The basic body plan of a cnidarian is a sac with a cen-tral digestive compartment, the gastrovascular cavity.A single opening to this cavity functions as both mouth and anus. Eyes are usually present, but there are no sensory appendages or parapodia. Cephalic or Head Region: It is composed of the first five segments. the oligochaetes, which can have a variable number of segments, leeches always have two pre-oral and 32 post-oral segments. With the exception of one small group, setae are absent. Hirudinea (leeches) True leeches have 34 body segments. The remaining 20 segments contain the reproductive organs, the tail and the anterior suction cup. The body of the medicinal leech is composed of 34 segments. The leech has a small sucker on its head. The central nervous system of the leech consists of a chain of very similar ganglia along a ventral nerve cord. MORPHOLOGY Leech is vermiform, bilaterally symmetrical and metamerically segmented animal that has a broad posterior sucker for attaching to substratum. Leeches can also swim by undulation of the 4 General Zoology Laboratory. ( 9)At either end of the leech, adhesive sucker is present. It is a muscular disc, circular in Outline. 3. Similarly, four body segments fuse to create the anterior brain. Question 6. The segments are arranged one behind the other. Correct answer: b) 33 segments View explanation. Leech has two suckers. Fig. I have examined the embryonic events which determine the total number of segments in the glossiphoniid leech Helobdella triserialis. Each segment is further superficially subdivided into rings or annuli. tion of other annelids, the leech body is generally flattened dorsoventrally. Three. The posterior sucker is formed by the fusion of the last 7 segments. The adult leech has 32 body segments (Fig. The segments of a leech are difficult to distinguish externally because they have been secondarily divided into sections called: Annuli. These external rings, however, are only superficial struc­tures and do not represent the actual number of true segments or somites in the body, the number of which is only 33. They lack setae and parapodia. The body of leech is metamerically divided into 33 segments. There are three varieties. Body segments. Leeches: the benefits of using leeches in medicine Best answer. A leech has a relatively small and fixed number (30-35) of body segments, although its body has a large number of superficial groove-like markings giving it the appearance of more extensive segmentation. The local leech has a cylindrical, dorsoventrally flattened body divided into thirty-three or thirty-four segments. (11)The posterior sucker is composed of the last seven segments. Leeches are segmented worms that belong to the phylum annelida and compromise the subclass hirudinea. Anterior to and posterior segments are modified into suckers. 1 Answer +1 vote . 3.2 Anatomical structure of the medicinal leech … A clitellum is present in the mid-region during the reproductive period. Leeches are dorsoventrally anteriorly. In comparison, the body of the dark brown leech was observed to have dark brownish body colour with black line and square pattern along the dorsal side, black stripe at … cation and incipient characterization of leech homeo-box-genes which are related to the genes that control segmental identity in other organisms. 5. The clitellum of a leech spans ___ body segments. The leech is a type of worm called an annelid, which has a body divided into similar parts, or segments.Annelids include marine bristle worms (class Polychaeta, 10,000+ species), earthworms (class Oligochaeta, 10,000+ species), and leeches (class Hirudinea, 700 species). The leeches have modified patterns of body-wall muscles and coelom. The entire body of a leech is divided externally into a large number of rings or annuli separated by transverse grooves. If no The leech body plan features an increased integration and a decreased modularity between segments relative to other annelids. According to the latest analysis, leeches have 34 internal segments. Question 7. Annelid - Annelid - Leeches: Leeches have 34 segments, and elongation occurs by the subdivision of these segments. 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