Consider the following kinds of organisms: 1. Copepods 2. Cyanobacteria 3. Diatoms 4. Foraminifera Which of the above are primary producers in the food chains of oceans?
- A.1 and 2
- B.2 and 3
- C.3 and 4
- D.1 and 4
Correct answer
Explanation
The correct answer is B, 2 and 3. Cyanobacteria and diatoms carry out photosynthesis, so they are phytoplankton, the primary producers at the base of ocean food chains.
Primary producers make their own food from sunlight, water and carbon dioxide. In the sea this job is done mostly by microscopic phytoplankton. Diatoms are single-celled algae with glass-like silica walls and are among the most productive organisms on Earth, giving a large share of the oxygen we breathe. Cyanobacteria, once called blue-green algae, are photosynthetic bacteria; tiny forms such as Prochlorococcus and Trichodesmium are abundant in warm seas, and some also fix nitrogen.
Copepods (1) are small crustaceans, the most common zooplankton; they eat phytoplankton, so they are primary consumers, not producers.
Foraminifera (4) are amoeba-like protists with chalky shells that feed on other plankton and organic matter; they are consumers too.
So A, C and D, which include copepods or foraminifera, are wrong.
Exam tip: phytoplankton (diatoms, cyanobacteria, dinoflagellates) = producers; zooplankton (copepods, krill, foraminifera) = consumers.
Practice Questions
View allConsider the following :
1. Battery storage
2. Biomass generators
3. Fuel cells
4. Rooftop solar photovoltaic units
How many of the above are considered "Distributed Energy Resources"?
- A.Only one
- B.Only two
- C.Only three
- D.All four
Show answer
Battery storage, biomass generators, fuel cells and rooftop solar units are all small, local sources that generate or store power close to where it is used, which is what Distributed Energy Resources are.
Read the full explanation →Due to some reasons, if there is a huge fall in the population of species of butterflies, what could be its likely consequence/consequences ?
1. Pollination of some plants could be adversely affected.
2. There could be a drastic increase in the fungal infections of some cultivated plants.
3. It could lead to a fall in the population of some species of wasps, spiders and birds.
Select the correct answer using the code given below :
- A.1 only
- B.2 and 3 only
- C.1 and 3 only
- D.1, 2 and 3
Show answer
Butterflies are pollinators and also food for many animals, so their decline would hurt pollination and their predators; it has no direct link with fungal diseases of crops.
Read the full explanation →Consider the following statements :
1. Lions do not have a particular breeding season.
2. Unlike most other big cats, cheetahs do not roar.
3. Unlike male lions, male leopards do not proclaim their territory by scent marking.
Which of the statements given above are correct ?
- A.1 and 2 only
- B.2 and 3 only
- C.1 and 3 only
- D.1, 2 and 3
Show answer
Lions breed at any time of year and cheetahs cannot roar, but male leopards do mark their territory with scent.
Read the full explanation →Which one of the following National Parks lies completely in the temperate alpine zone?
- A.Manas National Park
- B.Namdapha National Park
- C.Neora Valley National Park
- D.Valley of Flowers National Park
Show answer
Set high in the Garhwal Himalaya of Uttarakhand, roughly between 3,200 and 6,600 metres, it lies wholly in the temperate alpine zone.
Read the full explanation →Consider the following statements :
Statement-I : Carbon markets are likely to be one of the most widespread tools in the fight against climate change.
Statement-II : Carbon markets transfer resources from the private sector to the State.
Which one of the following is correct in respect of the above statements?
- A.Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I
- B.Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-I
- C.Statement-I is correct but Statement-II is incorrect
- D.Statement-I is incorrect but Statement-II is correct
Show answer
Carbon markets are a leading climate tool, but they work by moving money between emitters and those who cut emissions, not from the private sector to the State.
Read the full explanation →