MODES OF NUTRITION

MODES OF NUTRITION

1. AUTOTROPHIC

   • Autotrophic mode of nutrition is the mode of nutrition in which organisms make their own food by converting simple inorganic materials (like carbon and water) into organic compounds(like glucose)
     • PHOTOAUTOTROPHIC
       • They use sunlight as their source of energy. Example: plants, blue green bacteria, some bacteria, some protists(like euglena, diatoms)
     • CHAEMOAUTOTROPHIC
       • They use chemicals as a source of energy. Example: Iron bacteria, Sulphur bacteria, Nitrifying bacteria

2. HETEROTROPHIC

   • Heterotrophic mode of nutrition is the nutrition in which organisms can not create their own food and depend on autotrophs for their food directly or indirectly.
     • SAPROTROPHS
       • They obtain food from dead and decay.
         • Mode of intake is absorptive
           • Digestion occurs outside (extracellular)
     • PARASITIC
       • They derive their food from a living host.
         • Based on amount of nutrients required from host
           • COMPLETE
             • Get all the required nutrients from the host
               • Example: Cascutta
           • PARTIAL
             • Get some required nutrients (like nitrogen) from the host.
               • Example: Santalum, Mistletae
         • Based on place of living
           • ECTOPARASITE
             • outside the host
               • Example: lice, leech, mosquito
           • ENDOPARASITE
             • inside the host
               • Example: Tapeworm, Roundworm
     • HOLOZOIC
       • engulf solid food
         • The holozoic nutrition is that nutrition in which an organism takes the complex organic food materials into its body by the process of ingestion, the ingested food is digested and then absorbed into body cells of organisms.
           • Digestion occurs within the body.
     • Sanguivorous
       • feed on blood