| Multicellular Organism |
Website Links For Organism |
Information AboutMulticellular Organism |
| CATEGORIES ABOUT MULTICELLULAR ORGANISM | |
| developmental biology | |
| SHOPPER'S DELIGHT | |
|
A group of similarly differentiated cells performing a function in a multicellular organism is known as a Tissue . Although some Single-celled Organism s, such as Myxobacteria , have differentiated cells, the differentiation is less dramatic than that typically found in multicellular organisms. A multicellular organism can work on a number of levels. For instance, a Sponge works on a cellular level as the different cells are almost like many separate Organism s co-operating together for a common goal. This is illustrated by the fact you can put a sponge in a blender and the cells of the sponge will aggregate again to form another sponge. They have no Tissue s, Organ s or Organ System s which require a higher level of organisation. More advanced organisms such as Jellyfish , Coral and Sea Anemones work on a tissue level of organisation, as their cells can aggregate to form different tissues. For instance, a jellyfish has an outer epidermis and an inner gastrodermis, an example of different tissues to serve a different purpose. More advanced still are organisms with an organ level of development, whereby groups of tissues form organs such as a primitive brain in Platyhelminthes (merely a grouping of ganglion cells). Finally, the most advanced organisms (like mammals) have Organ System s whereby groups of Organ s act together for a common purpose with each organ focusing on a particular task. An example would be the Digestive System . for instance the Small Intestine focuses on absorption of food into the blood stream, the Stomach on crushing food and killing bacteria with its acidic environment, the Pancreas for creating Enzymes that catalyse the digestion of food, etc. Multicellular organisms must solve the problem of regenerating the whole from Germ Cell s (i.e. Sperm and Egg cells), an issue that is studied in Developmental Biology . The overall spatial organization of differentiated cells is a topic of study in Anatomy . Multicellular organisms can suffer from Cancer , when cells fail to regulate their growth within the normal program of development. SEE ALSO Cellular Differentiation Evolution Of Multicellularity |