Which one of the following is not used for construction of ecological pyramids?

1. Dry weight

2. Number of individuals

3. Rate of energy flow

4. Fresh weight

In a lake that undergoes thermal stratification, blooms of phytoplankton tend to occur

1. before thermal stratification 

2. after thermal stratification 

3. at the onset of thermal stratification 

4. at the mid-phase of thermal stratification 

Photosynthesis is absent in 

1. aphotic layer                 

2. photic layer        

3. benthic layer                 

4. pelagic layer.

The given type of ecological pyramid represents

1. pyramid of numbers in tree ecosystem

2. pyramid of biomass in a fallow land 

3. pyramid of biomass in a lake

4. energy pyramid in a spring

Which of the following zones of a lake is habitat for snails, slugs and microorganisms?

1. Littoral

2. Limnetic

3. Benthic

4. Profundal

Mr. X is eating curd/yoghurt. For this food intake in a food chain he should be considered

as occupying

1. first trophic level

2. second trophic level

3. third trophic level

4. fourth trophic level.

Given below is one of the types of ecological pyramids

This type represents

(1) pyramid of numbers in a forest

(2) pyramid of biomass in a fallow land

(3) pyramid of biomass in a lake

(4) energy pyramid in a spring.

In India, we find mangoes with different flavours, colours, fibre content, sugar content and even shelf-life. The large variation is on account of  

(1)  species diversity    

(2)  induced mutations    

(3)  genetic diversity    

(4)  hybridisation.

What is PAR range?

(1) 200 nm - 800 nm          

(2) 400 nm - 700 nm

(3) 350 nm - 550 nm         

(4) 600 nm - 100 nm

The bacteria which attack dead animals are 
(1) first link of the food chain and are known as primary producers.

(2) Second link of the food chain and are herbivorous

(3) third link of the food chain and are tertiary consumers

(4) the end of food chain and are decomposers.