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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

can you mix kc nd pressure
Khanyisile Reply
equation for dissociation
Amanda Reply
under which topic
acids and bases
Newton's law
How does a catalyst affect the rate of chemical reaction
Rebone Reply
it speeds up the reaction without being by the reaction. in other words it increases the Reaction rate by lowering the activation energy of a reaction
it only speed up the reaction not to affect the reaction
what is a compound?
Sithembiso Reply
define Doppler effect
Emihle Reply
It is the change in frequency of a wave in relation to an observer who is moving relative to the wave source.
Doppler effect is the change in frequency or pitch detected by a listener because the velocity of the sound source is different from that of a listener relative to the medium of sound propagation
explain how color is an unreliable clue to.the identify minerals
Camille Reply
Hi I want to know where the topic for electric circuits are?
Zahra Reply
hello.. How to deal with Reactions rate?. i dont Understand them
Simphiwe Reply
Firstly you must know how energy changes during chemical reactions...secondly the collision theory.... Rate and extent of reactions.... And factors that affect the rate of chemical reactions... If u capture all the topic then this chapter will be easy for you the is no way you can fail it...
thank you
Heii.. I'm struggling with chemical equilibrium.
how do I attempt chemical equilibrium?
doppler effect question
Mabikinyane Reply
How do I differentiate from the formula of a listener who is moving away and who is moving towards the source
if the its away you will subtract on the numerator and add in the denominator but if its towards its the opposite
how cn I calculate sound of a source if it's unkown
Simphiwe Reply
Use what you were given. What were you given?
where can I find acids and bases
muravha Reply
how to calculate avarage power?
Bongani Reply
good result for bursary
Soluiswayi Reply
Good day Sir
Good day Mam
good day
How are you
4. A builder of mass 75 kg is carrying bricks up a flight of stairs. There are 40 steps, each 25 cm high and he takes 10 s to climb the stairs, carrying 15 kg of bricks at a time. Calculate the total power output of the builder during his climb at constant speed.
Asanda Reply
I want to know how to calculate.
mm I think it will be zero work an power due to a vertical climbing
How it was calculated 😕
1stly describe Hydrocarbon for me please
Magadi Reply
Compounds that consists of carbon and hydrogen atoms only.
Compounds that consists of carbon and hydrogen atoms only.

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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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