Nutrients and Metabolic Processes - Class IX

The human body can last weeks without food, but only days without water. The body is made up of 50 to 75 per cent water. Water forms the basis of blood, digestive juices, urine and perspiration, and is contained in lean muscle, fat and bones. It helps to maintain the temperature of the body.

DNA contains the genetic information necessary for the synthesis of RNA and thereby all proteins necessary for the cell to function. RNA is a sequence of nucleotides that contain information for the synthesis of proteins. Deoxyribose is a sugar present in the nucleotides of DNA. Proteins are also provide  information. 

Chloroplasts are green because they contain the green pigment chlorophyll in their thylakoid membranes. Chlorophyll is a pigment that absorbs red and blue light. So plants are green because chlorophyll reflects green light. 

Chlorides are inorganic mineral salts that are highly stable and are not affected by biological processes like decomposition or bacterial action.

Eutrophication, the excessive growth of algae, is primarily caused by the influx of inorganic nutrients like nitrates and phosphates into water bodies.

Inorganic salts, mineral acids, and metal compounds are chemical substances that do not contain carbon-hydrogen bonds, classifying them as inorganic pollutants when they contaminate the environment.

Autotrophs are organisms that produce their own food using sunlight (photosynthesis) or chemical energy, converting inorganic substances into organic matter.

Glucose is a simple monosaccharide sugar. It is a hexose sugar. It is an aldose sugar. Ingested carbohydrates are broken down into monosaccharides which are absorbed in the intestine. Glucose is absorbed in intestine. Glucose is also chief form of sugar in blood and circulates in blood to supply energy to visceral organs.

Calcium strengthens bones and teeth in our body. It is an inorganic substance which is later converted to its organic forms when it gets combined with carbon molecule.

Nutrients obtained by plants and animals are classified into two groups organic and inorganic. Inorganic nutrients are those that are not easily found in animals or plants. They are always converted into their organic forms. Ammonia is an organic nutrient generally found in animals for synthesis of various metabolite.

Nitrogen is one such element which is very important in plant growth because it is an essential part of the chlorophyll that is the site of photosynthesis.

Rhizobium is a nitrogen-fixing bacteria found in symbiotic association with the root nodules of leguminous plants. 

Photosynthesis is a metabolic process of formation of glucose from carbon dioxide and water in presence of light energy.

PPP or pentose phosphate pathway is an important pathway that takes place in the cytoplasm.

In NH3 (ammonia), nitrogen is in the -3 oxidation state, which is its most reduced form. In CO2, carbon is in the +4 state (oxidized); in H2O, hydrogen is in the +1 state; in sulphate, sulphur is in the +6 state.

 A limiting factor is simply anything in short supply that will limit the rate of photosynthesis. Photosynthesis has 3 limiting factors: light intensity, carbon dioxide concentration, temperature. Sometimes photosynthesis is limited by the concentration of carbon dioxide in the air. Even if there is plenty of light, a plant cannot photosynthesis if there is insufficient carbon dioxide as the light energy cannot be fully absorbed. 

A comparison of elements present in non-living and living matter is given in the table below:

Sodium chloride (NaCl) is a classic example of an inorganic compound, as it is an ionic salt lacking carbon-hydrogen bonds. Oil, fats, and nutrients (like proteins/carbohydrates) are organic compounds.

The body burns fat after first exhausting the contents of the digestive tract along with glycogen (carbohydrates) reserves stored in muscle and liver cells. During short periods of energy abstinence, the human body will burn primarily free fatty acids from body fat stores. After prolonged periods of starvation when the body has depleted its body fat, it begins to burn lean tissue and muscle (protein) as a fuel source.

Chemical energy is stored in the bonds that connect atoms with other atoms and molecules with other molecules. Because chemical energy is stored, it is a form of potential energy. When a chemical reaction takes place, the stored chemical energy is released. Chemical Energy - is really a form of potential energy and is the energy stored in food or chemical combinations. Radiant Energy - is a combination of heat and light energy.