Biology · General Awareness

Aquatic and Marine Biology

1,905 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

Which of the following is the longest living organisms in the animal kingdom?

  1. Cockle

  2. Scallops

  3. Geoducks

  4. Hyolitha

  5. Fordilla
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Geoducks are the longest-living organisms in the animal kingdom. The oldest recorded specimen was 168 years old but individuals over 100 years old are rare. Scientists speculate that the geoduck's longevity is the result of low wear and tear. A geoduck sucks water containing plankton down through its long siphon, filters this for food and ejects its refuse out through a separate hole in the siphon.

Multiple choice

Which of the following octopuses is considered by most experts from all over the world to make the best pet octopus?

  1. Octopus bimaculatus

  2. Atlantic pygmy octopus

  3. Caribbean reef octopus

  4. California two-spot octopus

  5. Amphioctopus fangsiao
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The California two-spot octopus (Octopus bimaculoides) is an octopus species found off the coast of California. One can identify the species by the circular blue eyespots on each side of its head. Due to their friendly temperament and relative hardiness, they are considered by most experts to make the best pet octopus.

Multiple choice

Which of the following is not a mollusc?

  1. Chiton

  2. Pila

  3. Prawn

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

Prawn is an arthropod, specifically a crustacean, characterized by jointed appendages and an exoskeleton. Chiton, Pila, and Unio are all molluscs.

Multiple choice

Pisces belong to which of the following categories?

  1. Oviparous

  2. Viviparous

  3. Saprophyte

  4. Parasite
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pisces (fish) are generally oviparous, meaning they lay eggs that hatch outside the mother's body. While some fish are ovoviviparous, oviparous is the standard classification for the group.

Multiple choice

Dog fish belongs to the class of

  1. Pisces

  2. Mammalia

  3. Reptilia

  4. Amphibia
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dog fish (Scoliodon) is a cartilaginous fish belonging to the class Chondrichthyes, which falls under the superclass Pisces.

Multiple choice

Whale belongs to which class?

  1. Reptilia

  2. Mammalia

  3. Aves

  4. Pisces
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Whales are aquatic mammals that breathe air through lungs, give birth to live young, and nurse them with milk. They do not belong to the classes of fish, reptiles, or birds.

Multiple choice

Animals that can live on land and water.

  1. Amphibious

  2. Carnivorous

  3. Herbivorous

  4. Graminivorous
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Amphibious animals are those that can live both on land and in water. Carnivorous, herbivorous, and graminivorous refer to dietary habits.

Multiple choice

What did the silver fantail do every morning to attract attention?

Directions: Read the passage and answer the question that follows.

I’ve grown fond of my two fish. They swim to the side of the tank every morning to watch me put on the jug for breakfast, begging silently to be fed. The big silver fantail goldfish does somersaults, as if putting on a show for his meal. He is a beautiful iridescent white that shines with every colour of the rainbow as he darts around. His friend is a golden, sleeker model, with smaller fins and tail – built for speed.
Once, while cleaning their tank, I scooped them into a clean tank while I rinsed their home and replaced the weeds. The next day I noticed my beautiful fantail was sick. He moped at the bottom of the tank with none of his usual antics to get my attention. His little friend didn’t seem to mind – he ate all the food flakes while the fantail watched. A short while later, the sleeker goldfish began to nip the fantail on the fins, forcing him to move. At first I thought this was aggression towards a sicker fish, but I soon realised he was helping his buddy keep moving, to oxygenate his blood and help him heal. He’s a physiotherapist, I thought.

  1. It swam very furiously and attacked the golden fish.

  2. It did somersaults and tried to attract attention.

  3. It swam with its friend so as to show they were competing.

  4. He sat at the bottom of the tank.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The big silver fantail goldfish does somersaults, as if putting on a show for his meal.

Multiple choice

Aquaculture includes keeping of

  1. prawns

  2. mussels

  3. labeo

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

The practice of culturing fresh water fishes is known as aquaculture. Labeo is a fresh water fish. Prawns, mussels and oysters are marine fishes.