Course Content
Microscopes and Microscopy
MICROSCOPES AND MICROSCOPY OBJECTIVES By the end of this topic, the trainee should be able to: 1.Name various types of microscopes. 2.State the function of parts of a microscope. 3.Describe the use of compound light microscopes describe care and maintenance of compound microscopes. 4.Describe preparation of microscope slides
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The Cell
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define and explain meaning of terms. 2.State types of cells. 3.Describe the cell structure under the light microscope. 4.State the functions of cell organelles. 5.Describe the process of mitosis and meiosis. 6.Describe physiological processes of cells. 7.describe the techniques of cell isolation. 8.Describe the procedure of temporary cell preparation.
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Microorganisms
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Classify the major groups of microorganisms. 2.State the general characteristics of each group. 3.Explain their mode of nutrition and reproduction. 4.Describe culture media. 5.Describe culturing techniques for bacteria. 6.Describe methods for determining bacteria population. 7.Describe sterilization and disinfection techniques.
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Immunological Techniques
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define terms. 2.Describe types of immunity. 3.Describe types of immune cells. 4.Describe the lymphoid organs and tissues. 5.Describe serological and immunological techniques.
0/8
Herbarium Techniques
OBJECTIVES By the end of this topic , the trainee should be able to: 1.Explain terms 2.Describe importance of collecting and preserving herbarium specimens 3.Describe sources of herbarium specimens 4.Describe collection of herbarium specimens 5.Describe preservation of herbarium specimens 6.Describe display of herbarium specimens
0/8
Museum Techniques
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Explain terms. 2.Describe importance of collecting and preserving museum specimens. 3.Describe sources of museum specimens. 4.Describe collection of museum specimens. 5.Describe preservation of museum specimens. 6.Describe display of museum specimens
0/5
Vivarium Techniques
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Explain terms. 2.Describe importance of vivarium. 3.Describe essential features of a vivarium. 4.Describe construction of a vivarium. 5.Describe maintenance of a vivarium.
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Aquarium Techniques
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Explain terms. 2.Describe importance of aquariums. 3.Describe essential features of an aquarium tank. 4.Describe construction of an aquarium tank. 5.Describe maintenance of an aquarium tank.
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Laboratory Animals
OBJECTIVES The objective of this chapter is to give a better understanding of the technical requirements regarding handling, care and maintained of various laboratory animals In this chapter, we will; 1. Identify the various types of laboratory animals. 2.Discuss the general care and handling of laboratory animals. 3. Describe the various methods of restraining and humane killing laboratory animals 4.Discuss care of specific disease free (SPF)and Gnotobiotic animals
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Introduction to Ecology
OBJECTIVE By the end of this module, the trainee should be able to: 1.Explain terms. 2.Describe biotic and abiotic factors. 3.Explain adaptation of organisms to terrestrial and aquatic environment. 4.Describe the energy flow in ecosystem. 5.Explain estimation of population in ecosystem. 6.Describe influence of human activities on environment. 7.Describe basic biogeochemical cycles.
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Plant Anatomy and Physiology
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Describe of plant parts and tissues. 2.Describe functions of various plant tissues. 3.Describe processes in plants .
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Biology Techniques For Science Laboratory Technicians
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Transport of substances into and out of the leaf 

The leaf is designed to transport water, sugars, carbon dioxide and oxygen across its surface. Each of these involves separate processes and cells which we will discuss below.

Movement of oxygen and carbon dioxide Stomata are the site of gaseous exchange in the leaf. There are two major metabolic processes that take place in plants that involve the exchange of oxygen and carbon dioxide:

  • Photosynthesis:takes place during the day when the chloroplasts can absorb radiant energy from the sun. Photosynthesis requires carbon dioxide and releases oxygen as a by-product. Therefore, during daylight hours, the concentration of carbon dioxide is low in the leaf and the concentration of oxygen is high. As a result, during the day, carbon dioxide enters the leaf and oxygen is released.
  • Cellular Respiration:occurs continuously throughout the day and night. Cellular respiration requires oxygen and releases carbon dioxide as a waste product. During the day, the plant can use some of the oxygen from photosynthesis for cellular respiration. During the night, when photosynthesis stops, the concentration of oxygen in the plant drops and the concentration gradient switches: the concentration of carbon dioxide is high and the concentration of oxygen is low. Therefore at night time, oxygen enters the leaves, and carbon dioxide is released.

Movement of water into leaf

Water is constantly being lost by the leaf through transpiration. This results in the cells in the mesophyll having a lower water concentration than the vascular bundles. Water thus moves down a concentration gradient from the xylem vessel into the living cells of the mesophyll layer and to the surface of the mesophyll cell walls. This causes water to move up from the stem by means of transpirational pull. The movement of water is maintained because water molecules constantly evaporate into leaf inter-cellular air space out of the stomatal pore and into the atmosphere.

Movement of sugars

Chloroplasts found in the palisade layer capture radiant energy from the sun to make glucose via photosynthesis. This glucose is used to make the simple sugar sucrose. Sucrose is transported to the rest of the plant through the phloem vessels present in the vascular tissue in the leaf. Plants convert sugars to starch for long-term storage.

Opening and closing of stomata: The opening and closing of the stomata is important for gaseous exchange, transpiration and the movement of sugars. Stomata open when it is bright and when there is high humidity. When water concentration in the soil is low, indicating that the plant is dry, chemical changes in the plant result in the closing of the stomata.

Figure 4.41: Confocal microscope image of guard cells and stoma. The red-staining region is chlorophyll.

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