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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

Light with wavelength of 160nm is shone onto a metal plate with a work function of 8,5×10^-19J Determine 1.thr frequency of the light 2.the threhold frequency of the metal 3.Kenetic energy of the released electrons
Desire Reply
An 800 kg car travelling at 15 m.s down a 30° hill needs to stop within 100 m to avoid an accident. using energy calculations only determine the magnitude of the average force that must be applied to the brakes over the 100m.assume that the surface is frictionless
Mihlali Reply
What is Projectile?
Nontobeko Reply
how to convert cm to nanometr?
When two objects collide in the absence of friction which is observed
Ronny Reply
how to calculate impulse
Smanga Reply
why do esters with higher molecular weight not have have strong fragrances
Prudence Reply
what's a relationship between velocity and momentum?
Eliya Reply
The greater the velocity the greater the momentum
How to calculate velocity
Ibanathi Reply
v=s/t units is metres per second/km per hour
v=displacement/change in time= v=Xf-Xi/t
what happen when you add water on an ester
Rose Reply
 present to produce ethanoic acid and ethano
whats a functional isomer
what's a momentum
Teekayairs Reply
Momentum is the product of mass and velocity P=m×v
this is all about physics only or chemistry can be asked?
Physics only
how to calculate the change in momentum of a rocket is initially for 250s at rest with a mass of 2.55×10^5kg of which 1.8×10^5 is fuel.then the rocket engine is fired up for 250s during which 1.2×10^5kg of fuel is consumed.the speed of a rocket after firing is 2.78×10^9 in a forward direction
wich equation should I use if I'm given the momentum and the change in time..
Alakhe Reply
how to do IUPAC naming ?
Nomsakk Reply
u must first master the functional group of your parent chain
how to calculate a single resistor
one function of diode
to allow current to flow through one direction
one function of variable resistor
how to calculate speed
Mahlatsi Reply
Distance /time

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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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