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
-
Whale
-
Dolphin
-
Shark
-
Cow Fish
B
Correct answer
Explanation
The Gangetic River Dolphin was declared India's national aquatic animal in 2009 to raise awareness about conservation efforts for this endangered species. Found primarily in the Ganges and Brahmaputra river systems, it represents India's freshwater biodiversity.
A
Correct answer
Explanation
Sharks have skeletons made entirely of cartilage, not bone. Cartilage is a flexible, lightweight tissue that provides structural support while allowing greater maneuverability than bone. All other options - teeth, gills, and liver - are body parts that sharks do possess.
-
Marlin
-
Great blue shar
-
Sailfish
-
Swordfish
C
Correct answer
Explanation
Sailfish are recognized as the fastest fish in the ocean, capable of bursts up to 110 km/h (68 mph). They have large sail-like dorsal fins and streamlined bodies built for incredible speed. While marlin and swordfish are also fast swimmers (marlin can reach 80 km/h, swordfish 97 km/h), sailfish hold the official record. The option 'Great blue shar' appears to be a typo for 'Great blue shark,' which is not among the fastest swimmers.
-
Jams
-
Dragonfly lavae
-
Chicken feet
-
Fish eggs
D
Correct answer
Explanation
Caviar is processed salted roe (eggs) of sturgeon and other fish species. It's considered a luxury food item. The eggs are carefully harvested and cured. Jams, insect larvae, and chicken feet are unrelated to caviar.
-
another shark
-
a beluga whale
-
a sea turtle
-
a human
C
Correct answer
Explanation
Sharks are most likely to mistake surfers for sea turtles due to the silhouette similarity when paddling - both appear as oval shapes with limbs (surfboard arms, turtle flippers). Sharks don't typically mistake humans for other sharks, beluga whales (Arctic species), or intentionally target humans.
-
snout
-
teeth
-
dorsal fin
-
eyes
A
Correct answer
Explanation
Sharks have specialized sensory organs called ampullae of Lorenzini located in their snout (rostrum). These gel-filled pores detect weak electrical fields generated by muscle contractions in prey, allowing sharks to locate even hidden or buried animals. The snout houses these electroreceptors, not the teeth, dorsal fin, or eyes.
-
occur after a shark stalks a surfer or swimmer for up to an hour, attacking only after its prey is alone
-
occur in the morning or early afternoon, as sharks are usually sleeping in the late afternoon or early evening
-
occur when a shark mistakes a human for its usual prey
-
none
C
Correct answer
Explanation
Most shark attacks are cases of mistaken identity, where the shark confuses a human for its natural prey like seals or sea lions. This explains why many attacks are 'hit-and-run' - the shark bites, realizes the human isn't its usual prey, and releases. Sharks don't typically stalk humans for hours, nor are they selective about morning versus evening attacks.
-
will usually attack and bite anything in the water, whether they think it's prey or not
-
are usually very picky about what they attack, refusing to bite anything that they don't think is prey
-
usually attack prey as a display of dominance when they think another shark is acting too aggressively
-
none
B
Correct answer
Explanation
Great white sharks are selective predators that typically investigate potential prey before committing to an attack. They often approach cautiously, bump, or bite试探ally to determine if something is food. This picky behavior conserves energy and reduces risk of injury. They are not indiscriminate attackers nor do they attack primarily for dominance displays.
-
bull sharks
-
hammerhead sharks
-
tiger sharks
-
option 1 & 3
A
Correct answer
Explanation
Bull sharks are known for their aggressive, unpredictable attack patterns and are responsible for many near-shore attacks. They can survive in freshwater and often hunt in murky shallow waters where human encounters are more likely. While tiger sharks can also attack humans, the question singles out bull sharks as having the characteristic attack behavior referenced in the context.
-
great white sharks
-
tiger sharks
-
bull sharks
-
all of the above
C
Correct answer
Explanation
Bull sharks are widely considered the most dangerous shark species due to their aggressive nature, tendency to inhabit shallow coastal waters and freshwater rivers where humans frequently swim, and having one of the highest documented attack rates. While great white and tiger sharks are also dangerous, bull sharks' proximity to human populations makes them particularly hazardous.
-
green anaconda
-
saltwater crocodile
-
King cobra
-
Brothers Island Tuatara
B
Correct answer
Explanation
Saltwater crocodiles are the largest living reptiles, reaching lengths up to 7 meters and weights over 1,000 kg. Green anacondas are large snakes but generally smaller than saltwater crocodiles. King cobras are venomous but much smaller, while tuataras are relatively small reptiles endemic to New Zealand.
-
Alaska blackfish
-
Sea horse
-
Cat fish
-
Armorfish
B
Correct answer
Explanation
Seahorses are indeed among the slowest-swimming fish. They are poor swimmers that rely on their prehensile tails to grip onto sea grasses and coral, drifting with ocean currents rather than actively swimming. Their small dorsal fin beats at about 35-70 times per second but propels them very slowly.
-
sea horse
-
barracuda
-
angler fish
-
sail fish
D
Correct answer
Explanation
The sailfish is widely considered the fastest fish, capable of swimming speeds up to 110 km/h (68 mph). Their streamlined bodies and large dorsal fins (sails) make them exceptionally fast swimmers in short bursts. The barracuda is also fast but not as fast as the sailfish.
-
White snake
-
Jaragua Sphaero
-
virusago chimera
-
Virgin Gorda Least Gecko
B,D
Correct answer
Explanation
Jaragua Sphaero (dwarf gecko) and Virgin Gorda Least Gecko are among the smallest reptiles, both measuring about 16mm. Both are correct answers.
-
prawns
-
dry fish
-
raw snails
-
squids
C
Correct answer
Explanation
Escargots is a French dish that consists of cooked snails (not raw). The snails are typically prepared with garlic butter, herbs, and served in their shells. While the question says raw, the dish is actually cooked.