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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SUPPORT  SYSTEMS IN ANIMALS

In this chapter we will be studying the different types of skeletal structures. We will focus in particular on the human skeleton. You will be introduced to the main features and functions of the human skeleton. By focusing on specific structures of the human skeleton, we once more emphasise a common theme of our study of Life Sciences: that structure is related to function.

Skeletons 

The skeleton is the supporting structure of an organism. There are three different types of skeletons: hydrostatic skeletons, endoskeletons and exoskeletons.

  1. Hydrostatic skeleton: Water exerts pressure on muscular walls, for example, in jellyfish.
  2. Exoskeleton: The stable chitinous or mineralised outer shell of an organism, for example, the shell of a grasshopper or prawn.
  3. Endoskeleton: A cartilaginous or mineralized support structure inside the body, for example, in humans and other vertebrates.
  4. In this chapter we will be looking at support systems in animals and investigating the human skeletal system in some depth.

Hydrostatic skeleton 

A hydrostatic skeleton is a structure found in many cold-blooded and soft-bodied organisms. It consists of a fluid-filled cavity, which is surrounded by muscles. The cavity is called a coelom and in some animals this cavity is filled with a blood-like substance called haemocoel. The fluid presses against the muscles, which in turn contract against the pressure of the fluid. The fluid is incompressible and thus maintains a constant volume against which the muscles can contract. The hydrostatic skeleton prevents the collapse of the body. The muscles in the body act against the fluid and in doing so bring about movement. If the body is segmented, the pressure of the fluid is localised in a few segments at a time. Hydrostatic skeletons occur in flatworms, round worms, earthworms, starfish and slugs.

Advantages of a hydrostatic skeleton

  1. Fluid shape:This allows organisms with hydrostatic skeletons to fit through oddly shaped passages, which is useful for burrowing or swimming.
  2. Strength:Creatures with hydrostatic skeletons can squeeze between spaces and expand, making a ‘prying open’ movement which allows them to force their way into various regions of rock and soil surfaces.
  3. Healing:Healing takes place faster in organisms with hydrostatic skeletons than in organisms with bone structures. This is because the haemocoel contained within the hydrostatic skeleton is made up mostly of water, and thus, can be refilled quickly. This allows many organisms with hydrostatic skeletons such as earthworms to grow back their body mass after damage.
  4. Lightweight:The hydrostatic skeleton allows the animal to move in a more flexible manner as it requires very little muscle mass for movement.
  5. Circulation:The fluid cavity allows circulation of nutrients and waste.
  6. Protection:The hydrostatic skeletons cushions the internal organs of the animal from shock.
  7. Suited to environment:Hydrostatic skeletons are suited for life in moist or aquatic environments, depending on the animal’s adaptations.

Disadvantages of a hydrostatic skeleton

  1. Structure and surface for attachment:The hydrostatic skeleton lacks a structure and does not have surfaces for the attachment of muscles or limbs.
  2. Lack of protection:There is very little protection for the internal organs.
  3. Dessication:A moist or water habitat is essential for survival of these animals in order to prevent dessication (drying out).
  4. Limited strength:Terrestrial animals with hydrostatic skeletons cannot increase their body size as they would collapse under their own body weight.
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