NUTRITION IN ANIMALS – HETEROTROPHISM
Meaning and Types of Heterotrophism
- This is a mode of nutrition whereby organisms feed on complex organic matter from other plants or animals
- All animals are heterotrophs
- Their mode of feeding is also said to be holozoic to distinguish it from other special types of heterotrophic nutrition namely:
- Saprophytism
- Parasitism
- Saprophytism/saprotrophysim- occurs in most fungi and some forms of bacteria
- Saprophytes feed on dead organic matter and cause its decomposition or decay
- Parasitism is a mode of feeding whereby one organism called the parasite feeds on or lives in another organism called the host and harms it
Modes of Feeding in Animals
- Animals have developed various structures to capture and ingest food
- The type of structures present depend on the method of feeding and the type of food
- Carnivorous animals feed on whole animals or portions of their flesh
- Herbiverous animals feed on plant material
- Omnivorous animals feed on both plants and animal materials
Feeding in Mammals
- The jaws and teeth of mammals are modified according to the type of food eaten
- Mammals have different kinds of teeth
- Each type of teeth has a particular role to play in the feeding process
- This condition is described as heterodont
- The teeth of reptiles and amphibians are all similar in shape and carry out the same function
- They are said to be homodont
Also See