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.
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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
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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
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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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Circulatory systems in animals 

Transport systems are crucial to survival. Unicellular organisms rely on simple diffusion for transport of nutrients and removal of waste. Multicellular organisms have developed more complex circulatory systems.

Open and closed circulation systems 

There are two types of circulatory systems found in animals: open and closed circulatory systems.

Open circulatory systems

In an open circulatory system, blood vessels transport all fluids into a cavity. When the animal moves, the blood inside the cavity moves freely around the body in all directions. The blood bathes the organs directly, thus supplying oxygen and removing waste from the organs. Blood flows at a very slow speed due to the absence of smooth muscles, which, as you learnt previously, are responsible for contraction of blood vessels. Most invertebrates (crabs, insects, snails etc.) have an open circulatory system. The figure below  shows a schematic of an open circulatory system delivering blood directly to tissues.

               The Open circulatory system.

Closed circulatory systems

Closed circulatory systems are different to open circulatory systems because blood never leaves the blood vessels. Instead, it is transferred from one blood vessel to another continuously without entering a cavity. Blood is transported in a single direction, delivering oxygen and nutrients to cells and removing waste products. Closed circulatory systems can be further divided into single circulatory systems and double circulatory systems.

Single and double circulation systems 

The circulatory system is a broad term that encompasses the cardiovascular and lymphatic systems. The lymphatic system will be discussed later in this chapter. The cardiovascular system consists of the heart (cardio) and the vessels required for transport of blood (vascular). The vascular system consists of arteries, veins and capillaries. Vertebrates (animals with backbones like fish, birds, reptiles, etc.), including most mammals, have closed cardiovascular systems. The two main circulation pathways in invertebrates are the single and double circulation pathways.

Single circulatory pathways

Single circulatory pathways as shown in the diagram below consist of a double chambered heart with an atrium and ventricle (the heart structure will be described in detail later in this chapter). Fish possess single circulation pathways. The heart pumps deoxygenated blood to the gills where it gets oxygenated. Oxygenated blood is then supplied to the entire fish body, with deoxygenated blood returned to the heart

Double circulatory systems

Double circulation pathways are found in birds and mammals. Animals with this type of circulatory system have a four-chambered heart.The right atrium receives deoxygenated from the body and the right ventricle sends it to the lungs to be oxygenated.

The left atrium receives oxygenated blood from the lungs and the left ventricle sends it to the rest of the body. Most mammals, including humans, have this type of circulatory system. These circulatory systems are called ‘double’ circulatory systems because they are made up of two circuits, referred to as the pulmonary and systemic circulatory systems. Humans, birds, and mammals have a four-chambered heart. Fish have a two-chambered heart, one atrium and one ventricle. Amphibians have a three-chambered heart with two atria and one ventricle. The advantage of a four chambered heart is that there is no mixture of the oxygenated and deoxygenated blood.

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