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Hey There!</h2><h2>
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Answer:</h2><h2>_____________________________________</h2>
Class Crustacea belongs to the Phylum Arthropoda. It is a class itself thus it does not have any subphylum.
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Phylums are the groups and Phylum arthropoda is one of the 33 phylas of the Kingdom Animalia. Phylum Arthropoda has the largest phylum of the Animal Kingdom with variety of animals that include one million species. It has 5 classes.
- Class Merostomata
- Class Arachnida
- Class Crustacea
- Class Myriapoda
- Class Insecta
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- They are usually aquatic both marine and freshwater.
- Exoskeleton is hard and made up of chitin called carapace.
- Body is divisible into head, thorax and abdomen. Some animals have cephalothorax.
- Cephalothorax regions are formed by the fusion of head and thorax
- Head bears two pairs of antenna, one pair of mandible, two compound eyes with stalk.
- Respiration takes place by gills or through body surface
- Excretion is carried out by one pair of antennary glands or green glands.
- The thorax and abdomenal appendages may be modified for swimming, feeding, walking, resperation as well as reproduction.
- Sexes are separate
- Dimorphism is prominent
- Five walking legs for locomotion are present.
- Example: 1)free living are, Daphnia, Cyclops, Argulus, Sacculina, Prawn Crabs etc.
2)Parasite are, Barnacles and Sacculina.
3) Marine are Shrimps, Lobsters etc.
4) Sedentary crustaceans are Barnacle(Parasite), Prawns(Fresh-water living) etc.
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Answer:
Distinction of crude density and ecological density necessary and which one of these densities are greater is explained below in details.
Explanation:
Density measure in courses of the amount of territory possible as existence reservation is ecological density. Crude density incorporates all the property within the animal's reach whereas ecological density incorporates only that division of property that can actually be established by the species.
Answer: B. schistosomiasis
Explanation:
Swimmer's itch is also called as cercarial dermatitis. It appears as a skin rash. It is typically an allergic reaction which is caused by a parasite.
Swimmer's itch is the symptom of Schistosomiasis. It is a disease which is also called as snail fever. It is caused by the parasitic flatworm called as schistosomes. This parasite infects the urinary tract and intestine in humans. Other symptoms include the diarrhea, abdominal pain, bloody stool and blood in the urine.
Please find the answers CAPITALIZED below.
Mercury's SURFACE strongly resembles that of EARTH's SURFACE, with very large impact CRATERS
Mercury, the second densest of all planets shares an exterior similarity with the Earth's moon. Given the rough-like exterior feature of the moon, Mercury surface is scarred by craters due to the collisions of comets and meteroids.