English

Science (English Medium) Class 12 - CBSE Important Questions

Advertisements
Subjects
Topics
Subjects
Popular subjects
Topics

Please select a subject first

Advertisements
Advertisements
< prev  2061 to 2080 of 4827  next > 

Sea Anemone gets attached to the surface of the hermit crab. The kind of population interaction exhibited in this case is ______.

Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

Write the observations made at the end of Connell's field, experiment on barnacles on the rocky sea coasts of Scotland.

Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

Name any two categories of organisms that in general are adversely affected by competition.

Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

What would be the best method to measure the total population density of the number of fishes in river and why?

Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population and Population Attributes >> Life History Variation

Interaction between clown fish living among the stinging tentacles of sea anemone is an example of ______.

Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

"Abingdon tortoise in Galapagos islands became extinct within a decade on introduction of goats in the island." Explain giving reason.

Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

Many copepods live on the body surface of marine fish. This relationship is an example of ______.

Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

"Some species of insects and frogs have evolved with various specific features that help them from being detected."

  1. Justify the statement giving reasons.
  2. Mention any two such features.
Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

Observe the graph given below.

The graph represents inter-specific interaction between two species of Paramecia competing for the same resource in a culture medium. Paramecium caudatum and Paramecium aurelia were grown in separate cultures as well as in mixed cultures. It was found that each species grew in numbers according to the logistic equation.

a) Which species is competitively superior? Support it with the data provided in the graph.

b) State the underlying principle for the above result and name the scientist associated with this principle.

c) Explain the mechanism in which two or more species competing with each other can co-exist.

OR

Graphs A and B shown below depict interaction of two species. Which graph indicates Mutualism? Give reason.

A B
Appears in 1 question paper
Chapter: [11] Organisms and Populations
Concept: Population Interactions

Write the equation that helps in deriving the net primary productivity of an ecosystem.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Concept of Ecosystem >> Productivity

Why the pyramid of energy is always upright? Explain.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Ecological Pyramids

“The pyramid of biomass is not always upright.” Explain the statement.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Ecological Pyramids

Name the type of detritus that decomposes faster. List any two factors that enhance the rate of decomposition.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Concept of Ecosystem >> Decomposition

Write the different steps taken in humification and mineralisation during the process of decomposition.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Concept of Ecosystem >> Decomposition

Answer the following question.
Describe the inter-relationship between productivity, gross primary productivity, and net productivity.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Concept of Ecosystem >> Productivity

Answer the following question.
What is an ecological pyramid? Compare the pyramids of energy, biomass, and numbers.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Ecological Pyramids

Write the relationship between productivity, gross primary productivity, net primary productivity, and secondary productivity.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Concept of Ecosystem >> Productivity

'The pyramid of energy is always upright.' Explain

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Ecological Pyramids

Explain with the help of labelled diagrams, the difference between an upright pyramid of biomass and an inverted pyramid of biomass.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Ecological Pyramids

(a) Given below is a pyramid of biomass in an ecosystem where each bar represents the standing crop available in the trophic level. With the help of an example explain the conditions where this kind of pyramid is possible in nature.

(b) Will the pyramid of energy be also of the same shape in this situation? Give a reason for your response.

Appears in 1 question paper
Chapter: [12] Ecosystem
Concept: Ecological Pyramids
< prev  2061 to 2080 of 4827  next > 
Advertisements
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×