Page 187 - Biology_F5

Biology for Advanced Level Secondary Schools

The head bears one pair of antennae and a pairs of legs. Millipedes are made up of a
pair of mouthparts (jaws) while the trunk series of segments, whose number varies
is not divided into thorax and abdomen. greatly from one species of millipedes
They are scavengers that feed on decaying to another (Figure 3.51). Many of the
organic matter, such as leaves and compost. segments contain special glands that secrete
the third body segment of female.READING ONLY
a noxious chemical to repel predators.
Distinctive features of class Diplopoda The first segment behind the head does
Diplopods have unique features, which not have legs, but the rest of the segments
differentiate them from other Arthropods. have legs. Towards the end, some of the
(a) They have cylindrical bodies with segments have no legs. The number of
clearly defined head, followed by
similar segments. legless segments varies from one millipede
(b) They have many legs; with two pairs to another. Some species of millipedes have
hair or spiny appendages protruding from
of legs per segment in adults. their bodies. Its head is on one end of its
(c) Most millipedes are herbivorous, body, and is about the same diameter as
feeding mainly on decaying vegetation. the adjacent segment. Also the head has a

(d) Spiracles are located on the underside pair of antennae that helps the millipede to
of the body. sense the surrounding environment. One
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(e) Reproductive opening is located on pair of mouthparts (jaws) is on the front
part of its head and the eyes are fixed above
its jaws. Most millipedes have simple eyes
Structure of millipede that provide basic vision, but not all types
The millipede has elongated and cylindrical or species of millipedes have eyes.
body with each body segment bearing two

Figure 3.51: Structure of a millipede

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