Free Biodiversity and Variety of Life MCQs with Answers

891. The organs of locomotion in echinoderms are:

• A. Muscle feet
• B. Jet propulsion
• C. Parapodia
• D. Tube feet

Explanation: Organs of locomotion in echinoderms are tube feet. These are present along the edges of grooves present in the arms.

892. Fate of the blastomeres is foretold in:

• A. Echinoderms
• B. Hemichordates
• C. Arthropods
• D. Chordates

Explanation: Arthropods are proterostomes in which cleavage is determinate (fate of blastomeres is foretold). Each blastomere developed into its special structure.

893. Which one of the following is the primary host of liver fluke?

• A. Man
• B. Snail
• C. Sheep
• D. Dog

Explanation: Sheep is the primary host of liver fluke.

894. Which one of the following is an example of a free-living carnivorous flatworm?

• A. Liver fluke
• B. Tapeworm
• C. Dugesia
• D. Schistosoma

Explanation: Dugesia are camivores, and they eat other small invertebrates and dead or decaying animals.

895. Polymorphism is a feature exhibited by members of:

• A. Coelenterates
• B. Porifera
• C. Arthropoda
• D. Platyhelminthes

Explanation: Polymorphism refers to the occurrence of structurally and functionally more than two different types of individuals within the same organism. It is a characteristic feature of Cnidarians (Coelenterates), particularly the polyp and medusa forms, or of zooids within colonial organisms like those in hydrozoa.

896. In arthropods, the body cavity is in the form of:

• A. Coelom
• B. Pseudocoelom
• C. Haemocoel
• D. Enteron

Explanation: In arthropods, the body cavity is in the form of haemocoel.

897. Name of common gut roundworm parasite of humans and pigs.

• A. Ascaris lumbericoides
• B. Pheretima posthuma
• C. Lumbericus terresaris
• D. Hirudo medicinalis

Explanation: Ascaris worms inhabit the lumen of the small intestine, usually in the jejunum or ileus. They have a life span of 10 months to 2 years and then are passed in the stool.

898. _is a good example of polymorphism.

• A. Hydra
• B. Obelia
• C. Starfish
• D. Euplectella

Explanation: Polymorphism refers to the occurrence of structurally and functionally more than two different types of individuals within the same organisms. It is a characteristic icature of Cnidarians (Coelenterates), particularly the polyp and medusa forms, or of zooids within colonial organisms like Obelia.

899. In radial symmetry, all body parts are arranged around the central axis. Radial symmetry represents_mode of life.

• A. Sessile
• B. Active
• C. Streamlined
• D. Parasitic

Explanation: In radial symmetry all body parts are arranged around the central axis. Radial symmetry represents sessile mode of life.

900. Pseudo-coelomates have a body cavity but it is not true coelom. Which one of the following is included in the group?

• A. Planaria
• B. Earthworm
• C. Tapeworm
• D. Ascaris

Explanation: Ascaris belong to the phylum Nematoda of super phylum Aschelminthes. They have a cylindrical body without showing any metamerism, a pseudococl (false coelom) and a complete digestive tract lined by endodermal epithelium.