Free Biodiversity and Variety of Life MCQs with Answers

911. The central nervous system of chordates is:

• A. Ventral
• B. Ventral and hollow
• C. Lateral
• D. Dorsal and hollow

Explanation: The central nervous system of all chordates is dorsal and hollow.

912. Bulanoglossus and Saccoglossus are members of:

• A. Echinodermata
• B. Annelida
• C. Nematoda
• D. Hemichordata

Explanation: Balanoglossus and Saccoglossus belong to phylum hemichordata.

913. All are characteristics of mollusks except:

• A. Soft-bodied
• B. Triploblast
• C. Bilateral symmetry
• D. Pseudocoelomates

Explanation: "The explanation for this question will be added soon!".

914. The body cavity is truly divided in all of the following except:

• A. Molluscs
• B. Arthropods
• C. Annelids
• D. Roundworms

Explanation: "The explanation for this question will be added soon!".

915. Highly organized mesoderm represents:

• A. Complex organ formation
• B. Radial symmetry
• C. Simple organ formation
• D. Bilateral symmetry

Explanation: "The explanation for this question will be added soon!".

916. Which of the following is the outer layer of the mesoderm?

• A. Parietal
• B. Visceral
• C. Intestinal
• D. Muscular

Explanation: "The explanation for this question will be added soon!".

917. Which one of the following is correct about parazoa?

• A. Radial symmetry
• B. Triploblastic organization
• C. Indeterminate shape
• D. Indeterminate cleavage

Explanation: "The explanation for this question will be added soon!".

918. During embryonic development the mouth is formed at some distance anterior to the blastopore and the blastopore forms the anus in:

• A. Echinoderms
• B. Mollusca
• C. Nematoda
• D. Aschelminthes

Explanation: A. When blastopore develops into anus then these animals are called deuterostomates. Echinoderms and chordates are deuterostomates. B. Molluscs are protostomates , in them blastopore develops into mouth . C. Nematods are pseudocoelomates therefore they are not grouped into protostomes and deuterostomes. D. These are also pseudocoelomates.

919. Saclike digestive system is present in:

• A. Cnidarian
• B. Platyhelminthes
• C. Arthropoda
• D. Chordates

Explanation: Platyhelminthes has flat worms. They are triploblastic and have mouth which opens into a gut but no anus so their digestive system is termed as sac like.

920. Which one of the following is an example of a radial organism?

• A. Planaria
• B. Human
• C. Sea anemone
• D. Insects

Explanation: Sea anemone belongs to phylum Cnidaria, which are radially symmetrical.Radial symmetry is a property of an item (e.g., a shape or an animal) that can be divided into two matching halves by many different lines, which all intersect one another at a single point in the center.