The Effect of Sodium Chloride Concentration in Growing Medium on the Growth and Total Germination of Cress Seeds

The Effect of Sodium Chloride Concentration in Growing Medium on the Growth and Total Germination of Cress Seeds

Scenario

There are a number of things that can influence how/if a plant grows

and germinate. These include;

· Amount and intensity of sunlight.

· CO2 concentration of the air.

· Temperature and humidity of the atmosphere.

· PH of the water and soil.

· Salt concentration of the soil and water.

· Quality of the soil, i.e. Minerals and nutrients.

· Use of fertilisers and pesticides.

The dependant variable (DV) in this scenario is the germination and

growth rate of the seeds. The factors that effected the growth and

germination of the seeds where therefore the independent variables

(IV).

Introduction

Germination is triggered by the uptake of water into the seed, water

always moves from a place of higher water potential to a place of

lower water potential. Water potential is a measure of the tendency of

water to move from high free energy to lower free energy. Distilled

water in an open beaker has a water potential of 0 (zero), the highest

water potential possible. The addition of solute decreases water

potential. In cells, water moves by osmosis to areas where water

potential is lower. To release the food stored in seeds that help aid

the plant in its early growth, they must first hydrolysed. Hydrolysis

is a chemical decomposition process that uses water to split chemical

bonds of substances. There are two types of hydrolysis; acid and

enzymatic. Food stores are appropriate for enzymatic hydrolysis

because they contain cellulose.

The first stage of germination is imbibition. Th...

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... where to few results

collected to make an accurate statement about the growth rate or

germination, only a general pattern can be made from the results

gathered in this experiment, as there are only 3 different intervals

for measuring the growth. To make the experiment more accurate,

measurements need to be taken at much more closer intervals (eg every

few hours for the first few days) then daily after that. The results

produced from an experiment with that sort of structure, would yield

much more conclusive results as to rate of growth. Finally, again to

do with the serial dilution technique used, solutions should have been

prepared up from 0.1% to 1.0% in increments of 0.1%. This again would

yield a much more accurate representation of each concentration being

used, and maybe smooth out overall trends in the results.