Question

16. Which of the following statements is/are correct?
A. The endoskeleton made of Chitin and protein in arthropods serves as a waterproof barrier and support for walking on land.
B. Given the following on the organism:
I. An animal
II. Multicellular
III. has tissues
IV. Has a circulatory system
V. has a hard exoskeleton and jointed appendages
This organism could be a member of the Phylum Insecta
C. Arthropods have a closed circulatory system
D. Arthropods can be found in all habitats of Earth
E. Insects are arthropods

17. Which of the following statements is/are correct?
A. Leeches are members of the phylum Platyhelminthes
B. All platyhelminthes are parasites of other organisms.
C. Most, if not all, Platyhelminthes lack a coelom.
D. Given the following on the organism:
I. An animal
II. Multicellular
III. has tissues (diploblastic)
IV. Lacks a digestive tract
V. is asymmetrical
This organism could be a member of the Phylum Platyhelminthes
E. Platyhelminthes can not reproduce sexually

18. Which of the following statements is/are correct?
A. Nematodes are also known as 'segmented' worms.
B. Members of the Phylum Nematoda are all hermaphrodites
C. Given the following on the organisms:
I. An animal
II. Multicellular
III. has tissues
IV. Has a digestive tract
V. exhibits bilateral symmetry as an adult
This organism could be a member of the Phylum Nematoda
D. Nematodes possess a cuticle.
E. Some members of the phylum Nematoda are parasites

20. Which of the following statements is/are correct?
A. Molluscs can live in marine, and freshwater habitats but do not live in terrestrial habitats.
B. Given the following on the organism:
I. An animal
II. Multicellular
III. has tissues
IV. has a digestive tract
V. exhibits bilaterally symmetry as an adult
This organism could be a member of the Phylum Mollusca
C. Molluscs can produce a shell and the presence of a shell at one point in development is a requirement for inclusion into this phylum.
D. Lobsters are members of the phylum Mollusca
E. Molluscs have three main body parts, a muscular foot, a visceral mass, and a head

Answer 1

For question 16, correct answers are B, D and E.

Chitin and proteins are major components of the exoskeleton of arthropods and not the endoskeleton of the arthropods. They can act as a waterproof barrier and also as a support for an arthropod. Arthropods are invertebrates and most invertebrates lack an endoskeleton.

Organisms in the phylum Insects are animals, at multicellular, have tissues e.g. straighten muscle tissues adapter for movement. They have an open circulatory system, have a hard exoskeleton and joints appendages for movement. Arthropods have an open circulatory system where there are no blood vessels but blood flow in openly through the body cavity.