Biology. The nutrition of the organisms

Enzymes and their properties. Match.
Most of the chemical reactions that take place in the cells are made possible by enzymes or ferments, which are biocatalysts produced by the same cells and through which substantially increases the speed of chemical reactions.

Gut enzymes are what make possible the digestion of food. Without these enzymes, digestion would last days. Each enzyme acts on a single substance. For example, proteases act on proteins, amylase on starch, lipase on fats, etc.. Among the highlight properties of enzymes that are soluble in water and precipitated by alcohol.

Each yeast has a pH optimum of activity. For example, pepsin of the stomach is to act in an acid medium and trypsin of pancreatic juice in an alkaline medium. So if we take an acid and mixing it with a starch (lemon and rice) the amylase may not digest the starch.

The temperature also influences. Salivary amylase is inactivated at 0 C, or if this at very high temperatures. We can classify the hydrolytic and respiratory enzymes in .. Hydrolytic enzymes break down by hydrolysis immediate principles in their constitutional elementary units. Respiratory enzymes are oxidants and are primarily responsible for catalyzing the cellular respiratory processes.

Vitamins and their properties

Vitamins are organic substances that exist in food and in very small quantities are needed for vital functions. Vitamins are divided into two groups: water soluble (B complex and C) and soluble (vitamins A, D, E and K) The first need to be dissolved in water for absorption by the body and the second in oil.


Photosynthesis is a process that transforms organic carbon carbonic gas taken from the air or dissolved in water. The primary organic substance formed is glucose, which typically is stored in the form of starch. The substance capable of absorbing the light radiation is chlorophyll, the pigment that gives green plants. Chlorophyll in the function must distinguish two reactions. One is the light reaction, in which chlorophyll is excited by light and breaks the water molecule into its components, and the dark reaction in which carbon dioxide is converted to organic, which is used for energy obtained in the light reaction.

Cycles of C, N, S and P
Carbon cycle. Photosynthesis converts carbon-carbon organic mineral forming plant material, which happens after phytophagous animals and finally to the carnivores, returning again organic carbon to inorganic form by death and decomposition of living things.

Nitrogen cycle
. Green plants absorb, along with carbon, nitrogen in the form of nitrates from soil, which then form the amino acids. The animals take the nitrogen that with the death and putrefaction caused by bacteria, emerge as ammonia, nitrites and finally nitrates through the action of bacteria. Atmospheric nitrogen is also used by certain bacteria.

Sulfur cycle. Green plants take the sulfur in the form of sulfate, which comes to be present in the proteins. Go to the animals, and putrefaction, bacteria emerge as hydrogen sulfide. The soil bacteria further process in sulfuric acid and sulfate.

Phosphorus cycle. The phosphorus comes from apatite, magmatic mineral. The waters will dissolve and the roots of green plants absorb it. This cycle is characterized by always being surrounded by an atmosphere of oxygen.

*Automatic Translation