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

ENZYMES

POLYSACCHARIDES

PROCESS OF PHOTOSYNTHESIS

NUTRITION IN PLANTS

BIOLOGY PRACTICAL