Free Biodiversity and Variety of Life MCQs with Answers

1441. The given diagram represents a type of symmetry.Which of the following animal has this type of symmetry as shown in the diagram?

• A. Option A: Butterfly
• B. Option B: Starfish
• C. Option C: Human
• D. Option D: Crab

Explanation: Symmetry in biology refers to the balanced distribution of duplicate body parts or shapes. Radial symmetry, as depicted in the diagram, is a type where body parts are arranged around a central axis. Animals like starfish, which belong to the group Echinodermata, exhibit this type of symmetry. In contrast, bilateral symmetry is characterized by a single plane that divides the body into two mirror-image halves, as seen in humans, butterflies, and crabs.Therefore, the correct answer is Option B: Starfish, because they exhibit radial symmetry, which matches the diagram provided. Options A, C, and D are incorrect because these animals exhibit bilateral symmetry.

1442. The CORRECT feature of ostium and and osculum in the body of sponges is

• A. A
• B. B
• C. C
• D. D

Explanation: Sponges have multiple ostia through which water enters their body and single osculum through which water leaves their body. So option B is correct and option A,C and D are incorrect.

1443. The example of an animal which has a complete digestive system is

• A. jellyfish
• B. tapeworm
• C. liver fluke
• D. roundworm

Explanation: A complete digestive system is characterized by a digestive tract that has two separate openings: a mouth for ingestion and an anus for excretion. This allows for a more efficient and directional process of digestion and nutrient absorption. In this question, the roundworm is the correct example of an animal with a complete digestive system. Jellyfish have an incomplete digestive system with only one opening, which serves both as the mouth and the anus. Tapeworms lack a digestive system entirely because they absorb nutrients directly from the host's gut through their skin. Liver flukes, similar to jellyfish, also have an incomplete digestive system with a single opening. Therefore, the only correct choice is roundworm, which has a complete digestive system.

1444. In contrast to amphibians, reptiles

• A. have separate sexes
• B. respire through lungs
• C. lay eggs with soft and leathery shells
• D. cannot control their body temperature.

Explanation: In this question, the key difference between amphibians and reptiles is their ability to control body temperature. Reptiles, unlike amphibians, are ectothermic, which means they rely on external sources to regulate their body temperature. This makes option D the correct choice. The other options are incorrect as they describe characteristics that are common to both amphibians and reptiles, not unique to reptiles.

1445. In the classification of kingdom animalia, poriferans are included in subkingdom parazoa because they

• A. are found in water.
• B. have the ability to regenerate.
• C. demonstrate division of labour.
• D. show cellular grade of organisation.

Explanation: Poriferans are classified into kingdom parazoa because they lack formation of true tissues and have cellular grade of organizations. So option D is correct. Aquatic habitat, regenerative capability and division of labour is not the basis of this classification.

1446. The option that CORRECTLY identifies the type of endoskeleton and existence of jaws in a lamprey fish is

• A. A. Cartilaginous endoskeleton, no jaws
• B. B. Bony endoskeleton, jaws present
• C. C. Cartilaginous endoskeleton, jaws present
• D. D. Bony endoskeleton, no jaws

Explanation: Lampreys are a type of jawless fish known as agnathans. They have a cartilaginous endoskeleton, meaning their internal skeleton is made of cartilage rather than bone. Additionally, lampreys lack true jaws, a feature that distinguishes them from more advanced vertebrates known as gnathostomes, which have jaws. Therefore, the correct identification of a lamprey's endoskeleton and jaw presence is that they have a cartilaginous endoskeleton and no jaws.

1447. In kingdom animalia, beginning of cephalisation is evident in phyllum:

• A. Porifera
• B. Protozoa
• C. Coelenterata
• D. Platyhelminthes

Explanation: Cephalisation refers to the evolutionary trend of the development of a head region where nervous tissue becomes concentrated, forming a brain and sensory organs. This process is a significant step in the complexity of animal evolution. Among the given options, platyhelminthes, or flatworms, are the first group in the animal kingdom to exhibit this characteristic. They have a simple nervous system with a concentration of nerve cells forming a primitive brain and sensory organs at the anterior end, marking the beginning of cephalisation.

1448. The following diagram shows representative members of two classes of molluscus.The CORRECT identification of the type of symmetry found in I and II is:

• A. Bilaterally Symmetrical, Asymmetrical
• B. Bilaterally Symmetrical, Bilaterally Symmetrical
• C. Radially Symmetrical, Bilaterally Symmetrical
• D. Asymmetrical, Radially Symmetrical

Explanation: Molluscs are a diverse group of animals with various body plans. Bilateral symmetry means the body can be divided into mirror-image halves along one plane, which is common in many molluscs like bivalves and octopus.

1449. The class of phylum arthropoda that lacks antennae and true jaws is:

• A. Insecta
• B. Crustacea
• C. Arachnida
• D. Myriapoda

Explanation: The phylum Arthropoda is divided into several classes, each with unique characteristics. Arachnida is a class that includes organisms such as spiders, scorpions, ticks, and mites. Unlike other arthropods, arachnids lack antennae and true jaws; instead, they have chelicerae that are used for feeding.

1450. In molluscs, closed circulatory system is found in the class(es):I. bivalviaII. gastropodaIII. cephalopoda

• A. I only
• B. III only
• C. I and II
• D. II and III

Explanation: In the phylum Mollusca, the class Cephalopoda, which includes organisms such as octopuses and squids, is unique for having a closed circulatory system. This means their blood is contained within vessels, which allows for more efficient oxygen and nutrient transport.