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metabolism

i understand that metabolism is the sum of all chemical reactions that happen in the body

but i don't understand the verb metabolise. what does it mean

for example:
the bacterium E.coli normally metabolises glucose as respiratory substrate

Reply 1

Aadilkharl123

Original post by esmeralda123

I understand that metabolism is the sum of all chemical reactions that happen in the body

but I don't understand the verb metabolize. what does it mean

for example:
the bacterium E.coli normally metabolizes glucose as respiratory substrate

Metabolism is a term that is used to describe all chemical reactions involved in maintaining the living state of the cells and the organism. Metabolism can be conveniently divided into two categories:

Catabolism - the breakdown of molecules to obtain energy
Anabolism - the synthesis of all compounds needed by the cells

Metabolism is closely linked to nutrition and the availability of nutrients. Bioenergetics is a term which describes the biochemical or metabolic pathways by which the cell ultimately obtains energy. Energy formation is one of the vital components of metabolism.

Reply 2

Kallisto

Entertainment Forum Helper

Original post by esmeralda123

It means that all chemical reactions of metabolism, so catabolism and anabolsim, proceed at the same time. In terms of your given example, glucose is breaking down (catabolism) to start with the synthesis of energy in form of ATP to support physiological process in the cells (anabolism). Adilkharl123 gave a good general explanation.

Reply 3

macpatgh-Sheldon

Hi,

As explained by one person above, metabolism includes anabolism and catabolism.

Therefore, when a cell or organelle "metabolises" a substance, it could be anabolising it or catabolising it. In your example of "metabolises glucose", the process involved being respiration tells you that the glucose [C6H12O6] is being catabolised i.e. being broken down into smaller molecules, namely CO2 and H2O, together with the release of usable energy in the form of ATP.

In a different situation e.g. in the process where a liver cell performs the process of glycogenesis, the hepatocyte (hepato = of liver; cyte = cell) metabolises glucose in a building process of a polymer called glycogen; in this example the cell metabolises glucose once again, but this time anabolises it into a (much) larger molecule. The opposite process, where glycogen is catabolised into glucose units, is called glycolysis.

In a different example, the cell might metabolise haemoglobin [Hb] (incidentally a hepatocyte once again!) to break it down into its haem and globin components. The haem is then further metabolised to produce bile pigments (bilirubin and biliverdin), which are released into the duodenum (first part of ileum [=small intestine]) in the bile duct to be excreted in faeces. The globin part is broken down into its constituent amino acids..

This whole section in italics is where the cell catabolises haemoglobin, an example of the metabolism of Hb.

Hope this directly answers your Q.

M (specialist biology tutor)