Heterotrophs

Question 1

Heterotrophy

Answer 1

heterotrophs eat or feed on organic carbon molecules to derive carbon for their tissue and energy for their various activites

Question 2

Ecological Stoichiometry

Answer 2

relative abundance of C and N varies
- plants have have high C:N ratio
- animals, fungi, bacteria have low C:N ration

Question 3

What are the five elements and their functions that make up of biomass of plants, fungi and bacteria

Answer 3

1. carbon: provides structure to organisms
2. oxygen: part of water molecules
3. hydrogen: part of molecules
4. nitrogen: part of amino acid and nucleic acid
5. phosphorus: essential for cellular processes , such as ATP transfer

Question 4

Herbivory

Answer 4

• substantial nutritional chemistry challenges
• herbivores must overcome plant physical and chemical defences
• plants are poor food and animals must generally consume large amounts

Question 5

Carnivory

Answer 5

• consume nutritionally rich prey
• little C:N ration across animal species
• selection on nutritional requirements less strong and selection is stronger on ability and efficiency of capturing and consuming different prey

Question 6

Decomposer

Answer 6

can directly absorb nutrients through chemical and biological processes (fungi)

Question 7

Detritivory

Answer 7

• feeding on non-living organic matter
• dead plants are rich in carbon and energy but poor in oxygen
• fresh detritus may still have considerable chemical defences present

Question 8

Omnivores

Answer 8

-plant/fungi/animal matter
- very flexible foraging strategy
- enables organisms to exploit seasonally abundant resources at different times of the year and gain a lot of mass

Question 9

mixotrophs

Answer 9

gain energy from photosynthesis and from consuming organic material

Question 10

Examples of Heterotrophic plants

Answer 10

saprophyte, parasitic plant

Question 11

Functional response

Answer 11

the relationship between food availability and feeding rate

Question 12

What influences feeding rate?

Answer 12

• animals can only physically shove so much food in their mouths
• time to digest food
• time to find food
• time to handle/process food

Question 13

Functional Response Curves Type 1

Answer 13

• linear due to quick processing time
• uncommon

Question 14

Functional Response Curves Type 2

Answer 14

• feeding rate increases linearly at low concentration, at a slower rate at moderate concentrations, then levels off at high concentrations
• limited by food search and handling lower densities
• at higher densities: food widely available

Question 15

Functional Response Curves Type 3

Answer 15

• primarily differ in the rate of food intake in the lower range of prey density
• at low food density, feeding rate is lower than the other two types
• increases greatly at intermediate before levelling off

Question 16

Optimal Foraging Theory

Answer 16

describes how organisms feed as a optimizing process (maximizes or minimizes some quantity, such as energy intake or predation risk
- explains/predicts what/when/where an animal will eat

Question 17

Do plants forage?

Answer 17

• yes
• nutrients in soil, water and sunlight can be limiting factors