Biology · General Awareness

Aquatic and Marine Biology

1,834 Questions

This hub covers key concepts in aquatic and marine biology, including fish anatomy, marine animal behavior, and commercial fisheries. These topics are essential for general science sections in various competitive exams. Use these resources to test your knowledge of diverse aquatic ecosystems.

Marine animal adaptationsCommercial fisheriesFish anatomyAquatic ecosystems

Aquatic and Marine Biology Questions

Multiple choice

Why do fishes have a streamlined body?

  1. To respire in water

  2. To swim in water

  3. To lay eggs in water

  4. To maintain body temperature
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fishes have a streamlined body to swim in water. That means, the shape of their body is smooth and tapering, or narrow in front like the shape of an aeroplane.

Multiple choice

Which of the following vertebrates can live both on land and in water?

  1. Aves

  2. Pisces

  3. Amphibians

  4. Mammals
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Amphibians - ‘Amphi' means 'both' and 'bios' means life. Animals that spend some time on land must breed (mate and produce young ones) and develop into an adult under water. Amphibians possess both lungs and gills for respiration. For example, frogs, toads and salamanders. Therefore, they can live both on land and in water. 

Multiple choice

Which of the following pairs is not correctly matched?

  1. Hyla: Tree frog

  2. Draco: Flying lizard

  3. Octopus: Cuttle fish

  4. Ichthyophis: Limbless amphibian

  5. Paramecium: Slipper animalcule
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Octopus is commonly known as devil fish. Sepia is commonly known as cuttle fish.

Multiple choice

Which of the following is not a vertebrate?

  1. Oryctolagus

  2. Fish

  3. Sparrow

  4. Amphioxus

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Amphioxus (lancelet) is a chordate but not a vertebrate - it lacks a true vertebral column (backbone). It belongs to the subphylum Cephalochordata, which retains the primitive chordate characteristics (notochord, dorsal nerve cord, pharyngeal slits, post-anal tail) but never develops vertebral elements. Oryctolagus (rabbit), Fish, and Sparrow are all vertebrates.

Multiple choice

Which of the following is correct?

  1. Platypus lays eggs.

  2. All the organisms that fly are birds.

  3. Whales respire by gills.

  4. Fishes have cartilagenous skeleton only.

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Platypus is the only mammal that lays eggs instead of giving birth to young ones.

Multiple choice

Which of the following statements are true about planktons?

A. They are drifting organisms. B. They have no locomotory organs. C. They may be found on the surface or in deep waters. D. They are mostly pelagic plants and animals. E. They also include some small fishes.

  1. A, B and D

  2. B and E

  3. C, D and E

  4. A, B and E
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

These are the features of planktons. They are drifting organisms having no locomotory organs and they are mostly pelagic plants

Multiple choice

Which of the following animals do not have the power of locomotion?

  1. Liver fluke

  2. Corals

  3. Oysters

  4. Jelly fish

  5. Cockroaches
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Corals are sessile organisms, meaning they are fixed in place and do not move from that location. The other options (liver fluke, oysters, jellyfish, cockroaches) all have some form of locomotion.

Multiple choice

Which of the following are echinoderms?

  1. Sea star

  2. Sea urchon

  3. Sand dollar

  4. None of these

  5. All of these
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Sea stars, sea urchins (misspelled as 'urchon'), and sand dollars are all echinoderms. They share characteristics including radial symmetry (usually five-part), a water vascular system, and tube feet. 'All of these' is the correct answer as all three listed organisms belong to the phylum Echinodermata.