Biomass

Question 1

What is a pyramid of biomass?

Answer 1

Biomass is the total dry mass of living material in an organism multiplied by the number of organisms.
A pyramid of biomass can be constructed to represent the relative amount of biomass at each trophic level in a food chain.
Pyramids of biomass are almost universally pyramid-shaped, whereas pyramids of numbers can take many different forms.
The pyramid of numbers doesn’t take into account the size of the organism and represents the amount of energy at each level less accurately.
Pyramids of energy look similar to pyramids of biomass but represent chemical energy rather than dry mass.

Question 2

what does it mean by the transfer of biomass?

Answer 2

Energy is wasted at each trophic level in a food chain, meaning less biomass and energy is passed on to the next organism in the food chain.

Question 3

For example: producers

Answer 3

Producers only manage to trap approximately 1% of light energy from the sun.

Question 4

What is the general rule for transfer efficiency?

Answer 4

A general rule for transfer efficiency between all trophic levels is that 10% of energy from a given trophic level will be available to the next trophic level.
This progressive loss of energy usually means that there are fewer individuals at higher trophic levels - and usually fewer than five trophic levels in a food chain.

Question 5

An example of this:

Answer 5

Livestock eating plants, and humans then eating this livestock, is an example of inefficient energy transfer compared to humans simply eating the plants.
This is because there is an additional trophic level where energy is lost.

Question 6

what are the reasons for inefficient transfer of biomass?

Answer 6

At each trophic level in a food chain, energy is wasted. Energy is used for maintenance and growth, and it is lost in respiration and waste products.

Question 7

These are:

Answer 7

1. Growth - Energy is used to create new cells to allow organisms to grow.
2. Waste products - Not all food is digested.
   Some food is removed from the body as the waste materials urine and faeces.
3. Maintenance -Organisms need constant maintenance and repair, which uses energy.
   Damaged cells need to be repaired or replaced.
   Warm-blooded animals need to expend energy to maintain a suitable body temperature.
4. Respiration - Large quantities of glucose are used in respiration to produce energy.
   Highly mobile animals require a lot of energy to sustain their movement.
   Respiration produces waste products that are removed from the body.

Question 8

what trophic level tends to contain the most biomass?

Answer 8

level 1 - producers

Question 9

what is the general rule for transfer efficiency?

Answer 9

A general rule for transfer efficiency between all trophic levels is that 10% of energy from a given trophic level will be available to the next trophic level.

Question 10

Which of the following is not a reason for energy wastage in food chains?

Answer 10

Cold-blooded animals use energy to maintain their body temperature.