Vitamins are organic compounds that are
essential for the human body for proper health, growth, and normal functioning
of the body. If vitamins are not present in the body or is improperly absorbed,
the body is vulnerable to diseases due to the specific deficiencies.1 In
humans, vitamins, unlike macronutrients, are not energy sources but rather they
facilitate metabolic and physiologic processes. They act as a catalyst to
release energy stored in the macronutrients. Humans cannot synthesize the
needed amounts of these organic molecules. These molecules have to be obtained
through the intake of food.2
However, in recent years, synthetic substitutes such as vitamin tablets have
been consumed in greater quantities. It is available as an over the counter
drug which makes it more accessible.
When many of these drugs are outdated they
are disposed, mostly into toilets or drains. This eventually enters water
supplies or soil and into plants.3 In
this work the effect of these vitamins are tested on Pisum sativum, or more commonly known as peas.
1.1 Research Question
How does the effect of 0.2, 0.4, 0.6,
0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0% solutions of vitamin C and vitamin B1 affect
the length and mass of root and shoot of Pisum
1.2 Background Information
Classification of Pisum sativum
Species: P. sativum
Additional Information on Pisum sativum
Pea is a small round seed that is found in
the pod fruit Pisum sativum. They
belong to the family, Fabaceae or the
legume family along with beans and peanuts.
P. sativum is an annual
plant that is planted in the cool season in many parts of the world. A pea is
usually green or rarely yellow. The optimum temperature for the seeds are form
13 to 18oC. They don’t grow in the summer heat or tropical climates.
Peas are high
in fibre, protein, phosphorous, magnesium, copper, iron, zinc, lutein, and
vitamins A, B6, C, and K.
The parts of a
pea plant include the testa, embryonic axis (which includes the pulmula
hypocotyl, and radicula) and cotyledons. As it grows it develops roots, stem,
leaves, tendrils, and flowers. It reaches up to the height of 1.8m.
Pea plant haven
been used for experiments throughout the centuries. For example, Gregor Mendel
used it in his revolutionary experiments on heredity.
Factors Affecting Growth
Plants are affected by both abiotic
and biotic stresses. Abiotic stress is the impact of non-living factors on
plants, whereas, biotic stress is the impact of living organisms on plants.
Abiotic stresses include: pH, temperature, salt, and drought. Biotic stresses
include: bacterial and fungal infections.4
pH is the measure of the acidity or
alkalinity of the soil. It has a scale form 1 -14, 1 being the most acidic and
14 being the most alkaline. pH refers to he concentration of H+ ions (protons)
in the media.
pH of the soil has strong impact on
plant growth. Plants require an optimum pH, usually between 5.0 – 6.5.5
Changes in the pH changes the concentration of protons in the cytoplasm of the
plant cells. If these concentrations go beyond the optimum, structural
deformities could occur. This leads to the collapsing of cellular processes.4
pH can also indirectly affect plant growth. Lower pH causes decreased rates of absorption
of positive ions. While high pH causes nutrient levels to decrease and ionic imbalances.6
Like pH, temperature affect plant growth
in multiple ways. Each species has its own optimum temperature. When the temperature
fluctuates even slightly beyond this temperature range, biochemical process will
alter. But when the temperature increases or deceases 10oC -15oC
it will cause profound moderations. These include the decrease in the rate of metabolic
reactions, protein and enzyme denaturation, and reduction in the photosynthetic
activity of the chloroplasts.
1 Carpenter, Kenneth, A. Stewart Truswell,
Douglas W. Kent-Jones, and Jean Weininger. “Human Nutrition.” Encyclopædia Britannica. Encyclopædia Britannica, Inc., 19 Apr. 2017. Web. 01 Jan. 2018.
2 Carpenter, Kenneth, and Margaret J.
Baigent. “Vitamin.” Encyclopædia Britannica. Encyclopædia Britannica, Inc., 28 Dec. 2017. Web. 01
Melissa. “How to Dispose of Old Vitamins.” LIVESTRONG.COM. Leaf Group,
03 Oct. 2017. Web. 01 Jan. 2018.
4 Perry, Leonard. “PH for the Garden.” PH for
the Garden. N.p., n.d. Web. 01 Jan. 2018.
5 Bower, Doug, Doug Morgan, Koren Phillips, and Brett Roeth.
“The Effect of PH on the Grotwh of Green Beans (Draft 4).” The
Effect of PH on the Grotwh of Green Beans (Draft 4). N.p., 20 Oct.
2005. Web. 01 Jan. 2018.
6 Mohammad Pessarakli, Mohammad, ed. “Handbook of Plant and
Crop Stress, Second Edition.” Books in Soils, Plants, and the Environment (1999): 51-52. Print.