ISOLATION AND IDENTIFICATION OF MICROORGANISM IN STREAM WATER

CHAPTER ONE

1.0                                                       INTRODUCTION
Water is the one of the most common substances known and it is good solvent for many substances, water occur at room temperature as clear, colourless, tasteless liquid which freezing into ice at zero degree centigrade and boil at 1000c. it is essential for life on earth. 
According to World Health Organization (WHO) in 1967 is the most important need of living things, it is second only to the air we breath, in fact some scientist believe that all life began in water. Also water is a molecule that consist of two hydrogen atoms and one oxygen atom, when these atoms are heated to a high temperature they join to for water. It occurs in three natural states solid, liquid and gaseous states. Water and ice covered about 75% of the earth surface and water vapour is an important constituent of the atmosphere (Ababio 1985) It exists under major two types which include:. 
Surface Water: They include the streams, lakes, and shallow wells. The air through which the rain passes may contaminate the water.

Ground Water: They originate from deep well and subterraneous springs. This is virtually free of bacteria due to filtering action of soil deep sand and rock. However, it may be come contaminated when it flows along the channels. 
Water in Microbiology can be contaminated when it contains a chemical or biological poison or an infectious agent. These condition also apply to water which is polluted except that the agent or poison is often obvious and water carries an unpleasant taste or appearance. (Encyclopedia America 1988). 
Portability refers to the drinkability of water when it is fit for drinking, when unportable it is unfit for consumption due to some contaminant or pollutant (Earnet 1974) other sources of contamination are various types of establishments and agricultural farm etc. Possible sources of microbial contamination of a body of water are soil and agricultural run-off, farm animals, industrial waste, discharges from sewage treatment plants and storm water run-off from urban areas.  
Contamination by sewage or human excrement and pollution by animals causes the greatest danger associated with drinking water in most developing countries. So it is necessary to examine the quality of water before consumption.    
Monitoring and detection of indicator and disease causing microorganisms are a major part of sanitary microbiology. Bacteria from the intestinal tract generally do not survive in the aquatic environment. They are under physiological stress and gradually lose their ability to form colonies on differential and selective media (Prescott 7th Edition).

You May Also Like

EFFECTS OF INSTRUCTIONAL TEACHING AIDS ON LEARNING ATTITUDES OF ADULT LEARNERS IN ADULT LITERACY CENTERS IN ADO ODO OTA LOCAL GOVERNMENT AREA, OGUN STATE.

Lemmer and Dekker (1993) clearly state that no factor is more important for positive school outcomes than the children‟s perception of the teacher‟s attitude toward them and expectations. They claim that when students believe that their teachers care about them, see them as competent, respect their views and desire their success, they tend to work toward fulfilling those high expectations. Teachers‟ expectations of pupils‟ performance and abilities can operate as a self-fulfilling prophecy within a classroom (Lemmer and Dekker, 1993). There are tendencies for the performance of the pupils to conform to the expectations declared by the teacher. According to Shalveson and Marsh (1986), students‟ attitude towards their ability to influence their academic outcome does affect their performance. Schneider et al. (2012) argues that students‟ feelings, attitudes, and perceptions they hold about their academic ability that is, academic self-concept, does affect their performance. When students have low academic self-concept they shift to self-handicapping. This method shifts blame away from the individual, and allows them to have excuses for failure. Students are more likely to achieve high marks when they believe in their own capacities and do not feel anxious about the learning process, (Schneider et al., 2012). Shalveson and Marsh (1986) also states that Self-efficacy in mathematics affects students‟ willingness to take on challenging tasks and the amount of effort and persistence. Bandura (1994) cites that students were asked to what extent they believe in their own ability to handle learning situations in mathematics effectively, overcoming difficulties tackling them. Results showed that self-efficacy and self-concept did affect performance and was also a key impact on motivation.
Read More