Energy in a Food Chain

Question 1

What does biomass refer to?

Answer 1

• The total mass of organic material, measured in a specific area over a set time period
• (The mass of living material of the organism or tissue)

Question 2

What does NPP stand for? What does it refer to?

Answer 2

• NPP = net primary production
• the rate at which energy is transferred into the organic molecules that make up the new plant biomass is called net primary productivity

Question 3

What does GPP stand for? What does is it? What units is it expressed in?

Answer 3

• GPP = gross primary productivity
• the rate at which energy is incorporated into organic molecules by an ecosystem is the gross primary productivity
• it is usually expressed as units of energy per unit area per year

Question 4

What are known as heterotrophs? What do heterotrophs include?

Answer 4

• organisms that obtain energy as ‘ready-made’ organic matter by ingesting material from other organisms are known as heterotrophs
• heterotrophs include all animals, all fungi, most bacteria and some protoctists

Question 5

What do heterotrophs depend on and why?

Answer 5

• Heterotrophs cannot make their own food, instead they must consume it so they depend on produces aka autotrophs for their food

Question 6

What is a producer?

Answer 6

• an organism that makes it’s own food (aka autotrophs)

Question 7

What is a primary consumer?

Answer 7

• primary consumers, also called herbivores, are heterotrophs that eat plant material

Question 8

What is a secondary consumer?

Answer 8

• secondary consumers, also called herbivores, are heterotrophs that eat plant material

Question 9

What is the definition of a herbivore?

Answer 9

• an organism that feeds on plants

Question 10

What is the definition of a carnivore?

Answer 10

• an organism that eats mostly meat. or the flesh of animals

Question 11

What are decomposers? Are they heterotrophs?

Answer 11

• decomposers are species of bacteria and fungi that feed on the dead remains of organisms and on animal faeces
• like animals they are heterotrophs

Question 12

What is are detritivores? What are some examples of detritivores?

Answer 12

• detritivores are primary consumers that feed on dead organic material called detritus
• examples would be woodlice, earthworms and freshwater shrimps

Question 13

How is energy transferred through an ecosystem?

Answer 13

• energy is transferred from producers to primary consumers, then to secondary consumers and then sometimes tertiary consumers

Question 14

What is a trophic level used to show? What is transferred between trophic levels and how?

Answer 14

• trophic levels are used to show the position a species occupies in a food chain
• energy is transferred from one trophic level to the next trophic level by consumers

Question 15

What is the definition of a limiting factor?

Answer 15

• a limiting factor is something which inhibits or slows the rate of reaction when it is in short supply