Free Biodiversity and Variety of Life MCQs with Answers

2961. Which of the following is not present in the fish?

• A. Middle ear
• B. Internal ear
• C. Gills
• D. Fins

Explanation: Option A: Middle ear and external ear are not found in fishes. All tetrapods i.e. amphibians, reptiles, birds, and mammals have a middle ear with a tympanic membrane. Option B: Fishes do have internal ears that pick up sound through their body. Many fishes rely on their ears to find habitat and mates, swim and avoid predators. Option C: Gills are present in fishes as they have a major role in respiration as well as osmoregulation, excretion of nitrogenous waste, pH regulation, and hormone production. Option D: Fins are also present in fishes and they help in swimming (locomotion), balance, and stability.

2962. Vertebrate with one occipital condoyle is:

• A. pigeon
• B. frog
• C. monkey
• D. rabbit

Explanation: Occipital condyle is a rounded knob-like structure that is present at the base of the skull which articulates with the first vertebra. It helps animals to move their heads.Mammals and amphibians have two occipital condyles, reptiles and birds have only one. As monkeys and rabbits are mammas and frog is an amphibian, they all have 2 Ocs whereas a pigeon is a bird so it has one OC which is why it is the correct answer.

2963. In earthworms many Enzymes are present

• A. Typhlosole
• B. Intestinal caeca
• C. Esophagus
• D. Pharyngos mass

Explanation: The pharynx of an earthworm, particularly the pharyngeal mass, is where various digestive enzymes are secreted. These include protease, which breaks down proteins into amino acids, and mucin, which aids in softening the food. The other structures mentioned, such as the typhlosole, intestinal caeca, and esophagus, have roles in the digestive process but are not primarily responsible for enzyme production. The typhlosole increases absorptive surface area, the intestinal caeca have a minor role in digestion, and the esophagus is merely a passageway for food.

2964. Organs of locomotion in earth worm are:

• A. Papillae
• B. Setae
• C. Pseudopodia
• D. Cuticle

Explanation: Organs of locomotion in earth worms are setae. Setae are present on parapodia on the body wall or embedded in sacs.

2965. Two chambered heart is found in:

• A. Leopardfish
• B. Fish
• C. Crocodile
• D. None of above

Explanation: Fishes have two chambered heart which include an auricle and an ventricle. Auricle is responsible for taking in blood from body and ventricle pumps out the blood that has entered the heart through gills and give fresh oxygen to the blood

2966. Which of the following is a homoeothermic animal?

• A. Uromastyx
• B. Salamander
• C. Seahorse
• D. Kangaroo

Explanation: Homoeothermic animals are those animals which can maintain their body temperature irrespective of external temperature variation, i.e. they are warm blooded animals which include Birds, humans and other mammals.

2967. Which of these is a fresh water sponge?

• A. Sycon
• B. Leucosolenia
• C. Spongilla
• D. Euplectella

Explanation: Spongilla is the only freshwater sponge among the options provided. It is typically found in clean lakes and slow-moving streams. In contrast, Sycon, Leucosolenia, and Euplectella are marine sponges that inhabit different types of saltwater environments. Sycon and Leucosolenia are commonly found in shallower marine waters, whereas Euplectella, known as the glass sponge, is often located in the deep ocean.

2968. Which animal posesses an open circularity system?

• A. Amoeba
• B. Earthworms
• C. Grasshoppers
• D. Man

Explanation: Grasshoppers have an open circulatory system with a heart. Their blood just bathes over their cells.

2969. Which of the following group of animals run very fast?

• A. Digitgrade
• B. Unguligrade
• C. Plantigrade

Explanation: A digitgrade is defined as those group of mammals that solely walk on their toes only and not touching the ground with their heels for example dogs, cats etc. They are faster than any other group of animals. The word digit comes from a latin word "digitus" meaning toes, fingers while the word "grade" means walking.

2970. All of the following are nematodes except:

• A. Ascaris
• B. Neresis
• C. Trichinella
• D. Guinea worm

Explanation: Nematodes are free living or parasite, and live in soil, roots, human and animal intestine and muscles. Most roundworms are less than five cm in length and many are microscopic but some parasitic roundworms are more than one meter in length.