Why are the following 3 elements necessary for plant growth and development?

Question

carbon

hydrogen

oxygen

Answer 1

These elements are really necessary for plant breathing. Light energy is the "force" which holds the raw materials (the atoms of carbon, hydrogen and oxygen) together in the carbohydrate molecules synthesized during the process called photosynthesis.

Good luck for you!

Kristi

Answer 2

First of all, there is no tried and true way to see if these elements are lacking from a plant -- if they were lacking, the plant would not exist.

Carbon is the basis of organic chemistry -- and vicariously, the basis for all plant material.  Whether it is the seed that a vascular plant grows from or the spore that a moss would grow from, both have carbon in them.  So right from the start, you have carbon.

Hydrogen and oxygen come into the picture in the form of water (H2O)in a way to make the plant grow.  Going back to that seed or spore, you have to have water present in order for it to germinate.  A continuing supply of H2O is required in order for the plant to grow.

If anything, it is an abundance of these compounds that are noticed.  An abundance of carbon or hydrogen is easily balanced via the carbon cycle in the plant.  Too much oxygen in the form of ozone (O3)  This causes the plant to have the appearance that there are water-soaked spots on the leaf.

All and all, the reason why these cannot be shown in a deficient state is because they are the benchmarks that are required for a plant and are all readily available in the soil or air around the plant.  Other elements, like nitrogen, phosphorus, and potassium, are not always present and must be added to the growing media in order to be present.

Hope that helps you out!

Answer 3

A plant will die if there is much restriction on these three elements. They are basic requirements for life.

Those three elements are available to plants in two molecules, CO2 and H2O.  So if they cannot acquire the CO2 or H2O they die very quickly. The first symptom of deficiency would be wilting.

Plants are not able to ingest and digest food sources they must make their own from a basic inorganic carbon source. CO2 is the carbon fixed by plants into organic carbohydrates but H2O is also required in the reaction. The purpose of water is to provide electron ions and hydrogen ions to be used in the two linked reactions of photosynthesis that fixes carbon. Carbon fixation is how autotrophs produce their own food. They later use their food in cellular respiration that uses up the glucose in the presence of O2. Photosynthesis and respiration allows the plant to live and grow.

The atmosphere has no limits to the CO2, it will always be available. Water is the rate limiting factor in the photosynthetic reaction that provides the plant energy in a usable form. Photosynthesis works to rearrange the molecules CO2 + H2O with the energy from sunlight into the higher potential energy form of a carbohydrate (CHO), specifically glucose. The photons energy is converted to chemical energy and stored in the bonds of the glucose molecule.  Since water & light are required for photosynthesis to proceed they are both rate limiting to the process. The reaction steps begin by first splitting water apart for the hydrogens and the electrons as a means of moving energy and then to construct the glucose molecule. Glucose it later chained together into starch for food or cellulose for structure. Thus those three elements are necessary for inorganic carbon to become fixed so it can be used for growth in a plant.

Water is further tied to the plants ability to regulate water loss in high heat and low humidity. If the plant wilts it closes its pores called stomata. These pores are multipurpose and allow all gases to pass in and out of the plant. O2 plus water   vapor leave and CO2 moves in through here so if the plant wilts, the stomata close and all gas passage is halted.   This means if the plant lacks water the stomata close and the plant  lacks CO2 as well as water efficiently shutting down photosynthesis despite abundant sunlight. It can no longer make its own food.

Limits to photosynthesis

http://library.thinkquest.org/22016/phot...

http://www.neiljohan.com/projects/biolog...

Carbon fixation is the second step in photosynthesis after photolysis of water.

http://users.rcn.com/jkimball.ma.ultrane...

Water is also the means of moving the essential nutrients from the soil. Soluble forms of NPK are taken up by roots and moved in with water taken from the soil. When the stomata close all water movement in a plant stops because it is driven by the evaporation of water from leaves pulling water in & up from the roots by capillary action in whole plant transpiration.

Guard cells regulate stomatal closure to stop transpiration->

Flaccid they close the stoma, turgid they gape open & the stoma open.

http://www.emc.maricopa.edu/faculty/fara...

Answer 4

the plant takes in the oxygen to make it's food and then releases oxygen.not sure about the hydrogen.

Answer 5

Most photosynthetic plants gain its carbon in the form of CO2 from the atmosphere. As long as the plant is in an open environment it should be fine.

Hydrogen was gain from water (H2O), if the plant lack of water, you will know it from dry leaves and other symptons.

Oxygen is also a gas that it can obtain from air.