IGCSE Biology Paper-1: Specimen Questions with Answers 134 - 134 of 208

Question 134

Question

MCQ▾

Which of the following animal shown here is Not an arthropod?

Features of Arthropoda

Choices

Choice (4)

a.

A

b.

B

c.

D

d.

C

Answer

b.

Explanation

Features of Arthropoda

  • It is the largest phylum of the animal kingdom, covering about 80 % of the animals
  • Aquatic, terrestrial or aerial (only non-chordates which can be aerial) .
  • Exoskeleton of Chitin- a polysaccharide of N-acetylglucosamine.
  • Periodic removal of exoskeleton called Ecdysis or moulting- essential for growth.
  • Meteorically segmented.
  • Blood vascular system Open type (Capillaries – nt, Haemocoel + nt) . Blood pigment present or absent (insects) . If present it is Hemocyanin (having Cu instead of Fe) .
  • Respiratory structures- Gills, Book lungs and Tracheal tubes.
  • Excretory structures- Green glands (Antennal glands) , Coxal glands and Malpighian tubules.
  • Nervous system very well developed. Eyes simple or Compound.
  • Unisexual (Dioecious) with well-marked sexual dimorphism. Fertilization internal.
  • Development mostly indirect.

Examples:- Palamon (Prawn) - Nauplius and Met nauplius larva, Astacus (Cray fish) - Larva

absent, Cancer (Crab) - Zoea and Megalopa larva, Eupagarus (Hermit crab) , Squilla - Alima larva, Sacculina (parasite on crab) - Nauplius, Kentrogen and Cypris larva, Cyclops (Secondary host for Guinea worm) - Nauplius larva, Daphnia (Water flea) , Shrimp, Woodlice Butterfly, housefly, honey bee, wasp, louse, termite, moth, mosquito, dragon fly, Bed bug, Flea, Cicada, Silver fish (Lepisma) and Chironomus fly etc.

Developed by: