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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 impulse and how does it = to momentum
Robin Reply
what is physics
Jhon Reply
what is a catanation ?
Rithabele Reply
The ability of a few elements, most especially carbon, to yield chains and rings by forming covalent bonds with atoms of the same element.
different structural formula
Lucas Reply
different type of structural formula
primary,secondary and tertiary
how does the earth revolute
Kevin Reply
What is the momentum
Given Reply
The product of the object's mass and it's velocity
electric field def
what is secondary alcohol?
is when Carbon that is bonded with OH is also bonded to 2 carbons of the chain.
how is ester formed
Aubrey Reply
how is n ester formed
Alcohol reacts with a carboxylic acid
and the reaction is catalysed by sulphuric acid
An ester is form when an alcohol reacts a carboxylic acid and sulphuric acid is used as a catalyst which therefore eliminates water.
an athlete with a mass of 70kg runs at a velocity of 45km . determine the athlete's momentum
Lesedi Reply
Is that a velocity or something else
45km/h i guess
Change to m/s
45km/h = 12.5 m/s p=mv =70×12.5 =875 kg.m/s
what are the measures of the rates of reaction
Lesego Reply
Volume Concentration Temperature Pressure Surface Area
the principle of superposition of waves
Sfundo Reply
what is work
Kool Reply
is this a group chat
Nobuhle Reply
Hey can y'all define newton's 2nd law
If a resultant force act on an object...the object will accelerate in the direction of a resultant force,the acceleration of the object is directly proportional to the net force and inversely proportional to the mass of the object
how do you calculate tension force
use the formula Fnet=ma if there is tension connecting two objects
to calculate Tension, usually calculate acceleration first Draw separate free body diagrams for each body. Apply Fnet = ma to calculate Tension
Hi people
when a resultant force acting on an object the object will accelerate in the direction of a force at an acceleration directly proportional to the force and invesly proportional to the mass of the object.
Hey people
how does temperature affect the equilibrium position
Blessing Reply
an increased temperature increases the average kinetic energy thus in turn increases the number of effective collisions........
so...which reaction is favored between endothermic and exothermic .when temperature is increased..?
exothermic reaction because energy is realised to the surroundings as heat and light energy ....graphical so much energy is realised as reactants to form product and because temperature is high rate of reaction is fast which means there is a successful collision
an object will continue in a state of rest unless it is acted upon an unbalanced force
Junior Reply
Newton's Law 1
First Newton's Law
Newton's first law
newton first law
Newton's first law
when pressure is increased what happen to volume
Siphelo Reply
care to explain?
if pressure is applied to a pistol , the volume will decrease and particles will collide more frequently with the wall of a container .Each time they collide with the wall they exert a force on them .More collision means more force and the pressure will increase , that Boyle's Law
Because the volume has decreased , the particle will collide more frequently with the wall of a container and each time they collide with the wall of a container they exert a force on them.More collision means more force so the pressure will increase , that Boyle's Law

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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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