Tag: organisms and their environment

Questions Related to organisms and their environment

What happens in biological magnification?

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. A progressive increase in the level of energy transferred through trophic levels

  2. A progressive increase in the body weight through trophic levels

  3. A progressive increase in the number of organisms through trophic levels

  4. A progressive increase in the amount of harmful substances through trophic levels

Show answer
Correct Option: D
Explanation:

Biomagnification (or bioaccumulation) refers to the ability of living organisms to accumulate certain chemicals to a concentration larger than that occurring in their inorganic, non-living environment, or in the case of animals, in the food that they eat.  The contaminants include heavy metals namely mercury, arsenic, pesticides such as DDT, and polychlorinated biphenyls (PCBs) compounds which are then taken up by organisms because of the food they consume or the intoxication of their environment. These materials are highly present in a variety of household and industrial chemicals. The harmful substances then build up inside the organism’s cells. When organisms in the higher food chain consume the organisms containing the toxins below their trophic levels, the toxins gradually become concentrated in the higher food chain. Because this is a repetitive process in the ecosystem and throughout the entire food chain, the higher organisms are the ones that will accumulate most of the toxins.

So the correct option is 'a progressive increase in the level of energy transferred through trophic levels'.

As energy is passed from one trophic level to another, the amount of usable energy

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. increases

  2. decreases

  3. remains the same

  4. energy is not passed from one trophical level to another

Show answer
Correct Option: B
Explanation:
The transfer of energy from one trophic level to next trophic level follows 10 percent law known as Lindeman's law of trophic efficiency which states that the efficiency of energy transferred from one trophic level to the next higher trophic level is about 10%. Rest of the energy is lost in respiration. So the energy decreases as it is transferred to subsequent trophic levels.
So, the correct answer is 'decreases'.

Flow of energy is unidirectional in an ecosystem because in each trophic level.

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. Number of consumers is constant

  2. Number of consumers reduces

  3. Loss of energy is more than the amount of available energy

  4. Available energy is completely consumed by consumers

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Correct Option: A

Which level in food chain has maximum energy?

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. Third Trophic Level

  2. Decomposers

  3. Herbivores

  4. First Tropic Level

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Correct Option: A

In which layer of atmosphere gases exhibit high kinetic energy?

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. Troposphere

  2. Stratosphere

  3. Thermosphere

  4. Mesosphere

Show answer
Correct Option: C

The energy used for all plant life processes is derived from ______________ radiation.

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. ultra violet

  2. infra red

  3. beta

  4. solar

Show answer
Correct Option: D

State whether the following statements are true or false .
The term entropy refers to steady state.

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

Entropy is a measure of the disorder or randomness in the system. It is a measure of how organized or disorganized energy is in a system of atoms or molecules. Greater the randomness of the system, greater is its entropy. While the steady state is a condition of a system or process (such as one of the energy states of an atom) that does not change in time. 

So, the correct option is 'False'.

Choose the correct answers from the alternatives given .
Endergonic reactions

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. are always coupling reactions

  2. can only occur if there is an input of energy

  3. have products with less free energy than the reactants

  4. all of the above are correct

Show answer
Correct Option: B
Explanation:
Endergonic needs an input of energy to create the products, which have more free energy as a whole than the sum of free energy of each of the reactants. An example of this type of reaction in biology is photosynthesis. This process depends on the reaction to absorb energy in the form of sunshine from the surroundings for it to occur. 
So, the correct option is 'can only occur if there is an input of energy'. 

Choose the correct answers from the alternatives given .
A living organism represents stored energy in the form of chemical compounds When an organism dies, what happens to.that stored energy?

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. All chemicals immediately lose their high-energy bonds

  2. All molecules immediately degrade into basic elements

  3. All energy immediately leaves, and that is. one manifestation that the organism is dead

  4. Chemical compounds in cells lose their organisation over time because there is no longer an input of energy to maintain the organised state

Show answer
Correct Option: D
Explanation:

There is constant input of energy needed for all the activities that go inside a living organism. Food is the source of this energy. When an organism dies, these activities or reactions are stopped which results in loss of organisation of chemical compounds in cells. 

So, the correct option is 'Chemical compounds in cells lose their organisation over time because there is no longer an input of energy to maintain the organised state'.

State whether the following statements are true or false .
An open system has access to environment for matter and energy.

botany organisms and their environment energy flow in food chain food chain and energy flow energy flow in ecosystem

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

 An open system is a system that has external interactions. An open system is defined as a system in exchange of matter with its environment, presenting import and export of matter and energy.

So, the correct option is 'True'.