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The fertiliser industry

The value of nutrients

Nutrients are very important for life to exist. An essential nutrient is any chemical element that is needed for a plant to be able to grow from a seed and complete its life cycle. The same is true for animals. A macronutrient is one that is required in large quantities by the plant or animal, while a micronutrient is one that only needs to be present in small amounts for a plant or an animal to function properly.


A nutrient is a substance that is used in an organism's metabolism or physiology and which must be taken in from the environment.

In plants, the macronutrients include carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P) and potassium (K). The source of each of these nutrients for plants, and their function, is summarised in [link] . Examples of micronutrients in plants include iron, chlorine, copper and zinc.

The source and function of the macronutrients in plants
Nutrient Source Function
Carbon Carbon dioxide in the air Component of organic molecules such as carbohydrates, lipids and proteins
Hydrogen Water from the soil Component of organic molecules
Oxygen Water from the soil Component of organic molecules
Nitrogen Nitrogen compounds in the soil Part of plant proteins and chlorophyll. Also boosts plant growth.
Phosphorus Phosphates in the soil Needed for photosynthesis, blooming and root growth
Potassium Soil Building proteins, part of chlorophyll and reduces diseases in plants

Animals need similar nutrients in order to survive. However since animals can't photosynthesise, they rely on plants to supply them with the nutrients they need. Think for example of the human diet. We can't make our own food and so we either need to eat vegetables, fruits and seeds (all of which are direct plant products) or the meat of other animals which would have fed on plants during their life. So most of the nutrients that animals need are obtained either directly or indirectly from plants. [link] summarises the functions of some of the macronutrients in animals.

The functions of animal macronutrients
Nutrient Function
Carbon Component of organic compounds
Hydrogen Component of organic compounds
Oxygen Component of organic compounds
Nitrogen Component of nucleic acids and proteins
Phosphorus Component of nucleic acids and phospholipids
Potassium Helps in coordination and regulating the water balance in the body

Micronutrients also play an important function in animals. Iron for example, is found in haemoglobin, the blood pigment that is responsible for transporting oxygen to all the cells in the body.

Nutrients then, are essential for the survival of life. Importantly, obtaining nutrients starts with plants, which are able either to photosynthesise or to absorb the required nutrients from the soil. It is important therefore that plants are always able to access the nutrients that they need so that they will grow and provide food for other forms of life.

The role of fertilisers

Plants are only able to absorb soil nutrients in a particular form. Nitrogen for example, is absorbed as nitrates , while phosphorus is absorbed as phosphates . The nitrogen cycle (Grade 10) describes the process that is involved in converting atmospheric nitrogen into a form that can be used by plants.

Questions & Answers

what is an isomer?
Kiba Reply
organic compounds with the same molecular formula but different structural formula
how is frequency directly proportional to kinetic energy max. and what is the relationship between the wavelength and the energy of a photon. eg if a photon with a greater wavelength and a photon with less frequency. what would be the energies. as in which one would be greater and why
Pearl Reply
relationship wave depend n enrgy greadt reflect of energy n the form of tex shape
what is Cell capacity?
liphelo Reply
what are hydrocarbons
Nyiko Reply
compounds that are made up of hydrogen and carbon only
They are compounds that consist only with hydrogen &carbon elements.
how do i calculate the work done on an object by a frictional force
Emmelda Reply
@ Emmelda it's W = FxCos180 Where 180° is the angle between Frictional force and where the object is going, it's always 180° because it opposes the motion. Then F is the magnitude of the force and x is the displacement
Ohm's law state that provide the temperature remains constant, that potential difference is directly proportional to the current flowing in the circuit
Ezile Reply
state ohms law
what does ohm's law state ?
Gugu Reply
ohm's law state that the potential difference across a conductor is directly proportional to the current in the conductor at constant temperature
ohm'law in metalic conductor is directly proportional to the potential difference provided the temparature
what is the principle on which generator is based
Nqobile Reply
electromagnetic induction
Explain it😌
what is spectrum
Mpeh Reply
It is a different combinations of frequency of light or any types of waves.
Heii guys what's the topic? Am neww
Vannessa Reply
In nuclear reactions, is it necessary that there must only be one element on the product side and a radioactive particle or you can have a product that are both radioactive particles?
Jobena Reply
conservative force is a force when the work done in moving the object between the two points that does not depend on the path way
Bongiwe Reply
what is conservative force?
Mh Reply
It is a force , that does not have any external features affecting it
what does the alternating current do
Kwanga Reply
what is definition of hydrocarbon
jessha Reply
it is the atoms that Contain of C atoms and H atoms only
You mean molecules
yea 💯
what's the definition of le chatelier?
what is electromagnetic
differentiate between DC motor and Ac generator
dc motor converts electrical energy into mechanical energy while ac generator converts mechanical into electical
DC has a Split-ring but then Ac has a slip-rings.
what's the other name of galvanic cell?
galvanic cell is also called Voltanic cell
is the chain whereby there is only Hydrogen and Carbon atoms only.
what is the difference between AC and DC moto
please check the answer from Ophola and Joyous
AC motor consists of 2 slip rings and a DC motor has a single split ring commutator
ac have slip rings n DC has split rings

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Source:  OpenStax, Siyavula textbooks: grade 12 physical science. OpenStax CNX. Aug 03, 2011 Download for free at http://cnx.org/content/col11244/1.2
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