This is the type of nutrition in which some organisms called heterotrophs feed on complex, ready-made organic food. In other words, their carbon source is organic.
Food serve the following three purposes in heterotrophs
1 . Energy supply, for vital activities
- Supply of material for building new parts, repairing worn-out tissues and cell maintenance
- Supply of enzymes. These are vitamins which the heterotrophs cannot synthesize.
Therefore, all heterotrophs depend on the synthetic activities autotrophs. A few organisms called photo heterotrophs use light energy to synthesize their food using organic raw materials. All of such organisms happen to be some bacteria. (question define photoheterophism)
Types of heterotrophic nutrition
These are: helozoic nutrition, parasitic nutrition. Some organisms are able to practice more than one form of these types.
Stages in heterotrophic nutrition
No matter the type, heterotrophic nutrition occurs through two stages: Digestion, followed y absorption
Digestion is the breaking down of large, complex food molecules into simpler, soluble ones(nutrients) .
Absorption is the uptake of nutrient from the region of digestion into the tissues of the organisms.