Introduction
Bacteria are minute single celled organisms that live around and inside our bodies.They are so small that scientists often use microscopes to view and study them and each bacterium is estimated to be a micrometer long in size (Bauman & Tizard, 2004). Bacteria just like any other living organism have some nutritional and environmental requirements to facilitate their growth. This paper shall therefore set out to explore and analyze the different requirements that facilitate the growth of bacteria on different environments.
Bacteria overview
According to Pommerville (2009), the term growth in bacteria does not mean in physical size but in population size of these organisms. In addition to this, he affirms that “a bacterium reproduces asexually through a process called binary fission”. This process involves “cytokinesis which refers to the inward pinching of the cell wall that separates it in two after it has grown large enough to divide (Alcamo, 2001).” Hugo & Denyer (2004) claim that in the optimum environment, bacteria can reproduce every 15-20 minutes and consequently, after 6hours a single bacterium can reproduce to a minimum of 131,000 bacteria.
Nutritional requirements for bacterial growth
Energy source
According to Winn & Koneman (2006), a prototroph bacterium use light as their primary source of energy during growth on the other hand, chemotropic bacteria derive their primary source of energy from the process of oxidation and reduction of chemical compounds.
Carbon source
Carter & Wise (2004) reiterates that carbon constitutes to most of the structural makeup of bacteria. As regarding to their carbon requirements, bacteria have been further classified into two categories; autotrophs and heterotrophs. He further states that the difference between these two bacteria is that “unlike heterotrophs, autotrophs have the ability to synthesize organic molecules from inorganic nutrients” (Carter & Wise 2004).
Nitrogen source
In the growth process, the synthesis of most amino acids required by bacteria depends largely on the nitrogen presence within the environment. In addition to this, bacteria also require minerals such as sulfur to synthesize certain vitamins, phosphorous, potassium, magnesium and trace elements to further aid in the process of growth. Water plays a pivotal role in the growth of these organisms because their molecular structure is 90% water. It is therefore among the most important nutritional requirement for the growth of any form of bacteria.
Environmental requirements
Temperature
Each bacteria species have very specific environmental needs for growth. Among these, temperature has been considered as one of the most important factors. The ideal temperature requirement for all bacteria is approximated to be between 30 and 40 degrees. The thermophiles tend to reproduce best at a temperature of 60 degrees while other species thrive at lower temperatures (Alcamo, 2001). Therefore for rapid bacterial growth to be realized, they have to be in the most optimum temperature. A deficiency of this may inhibit their growth or even kill the organisms.
Oxygen
Bacteria just like other living organisms rely highly on oxygen for cell function and growth. However unlike aerobic cells, anaerobic cell bacteria do not require oxygen for growth and as such, they have other sources of energy.
PH levels
“This refers to the levels of acidity or alkalinity within the growth environment” (Pommerville, 2009). According to Rudnick (2003) majority of the bacterial species do not do well in highly acidic environments. He further claims that this is because “the cytoplasms of most bacteria have a pH level of 7.0 which is in the neutral range.” As a result, it is important that these cells be in a very conducive environment in regards to the pH level if growth is to be realized.
Osmosis
Byrd & Powledge (2006) defines osmosis as “the diffusion of water across a membrane from an area of higher water concentration (lower solute concentration) to lower water concentration (higher solute concentration).” As mentioned earlier, bacteria are 80-90% water and they obtain the necessary nutrients for growth from their aqueous environment. As such, depending on the species, they require optimum osmotic pressure to facilitate their growth.
Theoretic background
The cell theory is among the cornerstones of modern day biology. It assumes that cells are the core structure of every living thing. According to Pommerville (2009), the theory states that; “all living things and organisms are made up of cells, new cells are created by older cells dividing into two and that cells are the basic building units for life.” From the discussion above, it is a fact that bacteria reproduces through binary fission and from their definition, they are singe celled organisms. This theory therefore justifies the existence of bacteria as well as their growth methodology.
In addition to this, the growth of bacteria is further supported by the fission theory. According to Phelan (2006) the fission theory assumes that parent cells of bacteria separate when they are large enough and consequently reproduce through the process of binary fission. The theory was formulated by Charles Darwin and was quickly assimilated into the world of microbiology. This was because it stood true when it came to the growth study as regarding to bacterial reproduction.
Another yet important theory that facilitated further understanding to bacterial growth requirements was the univocal generation theory which assumed that all reproduction originated from parent cells. Towarzystwo (2006) acclaims in his journal that all bacterial cells reproduce from parent cells through the process of binary fission. He further states that this theory has been used over the years to discard the claims brought forward by the spontaneous generation theory which assumes that living organisms can be developed from non living. According to the univocal theory, there must be a parent cell if reproduction is to occur.
Another theory that shed more insight into the growth of bacteria is the chromosome theory of inheritance. According to Gupta (2005), this theory assumed that all genes have chromosomes and that these chromosomes are the main carriers of the genetic materials. In relation to bacterial growth requirements, each species of bacteria has a different genetic makeup and as a result, they may require different nutritional and environmental needs to facilitate their growth. This theory has over the years aided microbiologists classify the bacteria through their chromosomes and as a result, they have been able to give specific information on the different species and their various growth requirements.
Conclusion
The different growth requirements for bacteria have been discussed in terms of the environmental and nutritional needs. Also, a theoretic background pertaining to this study has been offered. Arguably, bacteria play an important role in all living things and more research should be done to further understand their structure, mutative tendencies and functions. This will in the future help in establishing new ways through which bacteria can be used to further help humanity.
References
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Carter, G, R & Wise, D, J. (2004). Essentials of veterinary bacteriology and mycology. USA: Wiley-Blackwell.
Gupta, J. (2005). Cell and Molecular Biology. USA: Rastogi Publications.
Hugo, W, B & Denyer, S, P. (2004). Hugo and Russell’s pharmaceutical microbiology. Chicago: Wiley-Blackwell.
Phelan, J. (2009). What Is Life?: A Guide to Biology W/Prep-U. W. H. USA: Freeman.
Pommerville, J, C. (2009). Alcamo’s Fundamentals of Microbiology: Body Systems. L.A: Jones & Bartlett Publishers.
Rudnick, L, R. (2003). Lubricant additives: chemistry and applications. Chicago: CRC Press.
Towarzystwo, P. (2006). Polish journal of microbiology. Polskie Towarzystwo.
Winn, W, C & Koneman, E, W. (2006). Koneman’s color atlas and textbook of diagnostic microbiology. USA: Lippincott Williams & Wilkins.