Free Biodiversity and Variety of Life MCQs with Answers

• A. Spider
• B. Earthworm
• C. Trout Fish
• D. Star Fish

Explanation: Trout fish belong to the phylum Chordata, which is characterized by animals that possess a notochord at some stage of development, a…

• A. Aurelia
• B. Chaetopterus
• C. Euplectella
• D. Taenia

Explanation: Annelids are coelomates, meaning they have a true coelom, a fluid-filled body cavity lined by mesoderm tissue.Coelomates are animals that…

• A. Earthworm
• B. Grasshopper
• C. Leech
• D. Slug

Explanation: A grasshopper is an Arthropod so it has Malphigian tubules.Malpighian tubules are the excretory and osmoregulatory organs found in…

• A. Chondrichthyes
• B. Osteichthyes
• C. Urochordata
• D. Coelenterata

Explanation: Chondrichthyes includes sharks, rays, and skates. They are primarily marine and have a wide range of adaptations for hunting and survival…

• A. Cnidarians
• B. Protozoans
• C. Porifera
• D. Segmented worms

Explanation: The canal system in Porifera (sponges) is a unique and efficient water filtration system that facilitates feeding, respiration, and waste…

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

Explanation: In molluscs, the mantle is a vital tissue layer that serves multiple essential functions.

• A. Deuterostomes
• B. Protostomes
• C. Both (a) and (b)
• D. None of the given options

Explanation: Hemichordates, such as acorn worms, are deuterostomes, meaning their embryonic development follows the pattern where the anus forms before…

• A. Their body consists of two layers
• B. They have non-cellular mesoglea present
• C. They have a great degree of specialization in cells
• D. They have radial symmetry

Explanation: Triploblastic animals have three germ layers, allowing for organ specialization.

• A. Multicellular
• B. Radially symmetrical
• C. Bilaterally symmetrical
• D. Asymmetrical

Explanation: Parazoa is a subkingdom of animals that includes sponges (phylum Porifera) and lacks specialized tissues and organs, unlike other animals.

• A. Liver Fluke
• B. Snail
• C. Earthworm
• D. Tapeworm

Explanation: Liver Fluke - Correct. The liver fluke (Fasciola) has a complex life cycle involving snails and mammals (e.g., sheep or humans) as hosts.

• A. They kill the prey with the help of stinging cells
• B. They kill the prey with the help of tentacles
• C. They kill the prey with the help of spicules
• D. They kill the prey with the help of barbs

Explanation: They kill the prey with the help of stinging cells - Correct. Cnidarians have specialized stinging cells (nematocysts) in their tentacles…

• A. Mesoglea fibrous, predominantly medusoid
• B. Mesoglea cellular, both polyp & medusa
• C. Mesoglea fibrous, polypoid forms only
• D. Mesoglea, non-cellular, polypoids form

Explanation: Mesoglea fibrous, polypoid forms only - Correct. Class Anthozoa includes organisms such as corals and sea anemones, which exist only in…

• A. 1, 2 & 3
• B. 1 & 3
• C. 1 & 2
• D. 2 & 3

Explanation: 1 & 3 - Correct. Hirudinaria (a genus of leeches) lacks setae and parapodia and is a blood-sucking annelid.

• A. Dugesia
• B. Fasciola
• C. Taenia
• D. Hydra

Explanation: Taenia - Correct. Taenia (tapeworm) is an endoparasite that resides in the human intestines.

• A. Perissodactyla
• B. Caballus
• C. Ferus
• D. Equidae

Explanation: Horses belong to the order Perissodactyla, which is a group of mammals characterized by an odd number of toes on their hind feet.

• A. Occurrence of a drastic change in form during postembryonic development
• B. Presence of a segmented body and parthenogenetic mode of reproduction
• C. Presence of different morphic forms
• D. Alternation of generation between asexual and sexual phases of an organism

Explanation: An alternation of generation between asexual and sexual phases of an organism is referred to as metagenesis. E.g.

• A. Sugarcane roots
• B. Decaying fallen leaves and soil organic matter
• C. Soil insects
• D. Small pieces of fresh fallen leaves of maize, etc

Explanation: The correct answer is that Pheretima and its close relatives derive nourishment from decaying fallen leaves and soil organic matter.

• A. (A) and (D) respire mainly through body wall
• B. (B) and (C) show radial symmetry
• C. (A and (B) have cnidoblasts for self defence
• D. (C) and (D) have a true coelom

Explanation: The animals which possess true coelom are called eucoelomates or coelomates.

• A. Octopus
• B. Asterias
• C. Ascidia
• D. Fasciola

Explanation: Octopuses do not have a single external opening for both ingestion and egestion.

• A. Humans - Kidneys, sebaceous glands and tear glands
• B. Earthworm - Pharyngeal, integumentary and septal nephridia
• C. Cockroach - Malpighian tubules and enteric caeca
• D. Frog - Kidneys, skin and buccal epithelium

Explanation: Kidneys are the primary excretory organs in humans. They filter waste products and excess substances from the blood to form urine, which…