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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Introduction to Microscopes and Microscopy Techniques
Types of Microscopes
The Optical(Light) Microscope
Magnifications and Resolving Power of Microscopes
Use and Care of Microscopes
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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INTRODUCTION
The Cell Structure
The Cell Functions
Cell Division
The Cell Cycle
Mitosis
Meiosis
Similarities and Differences between Mitosis and Meiosis
Microscope Slides
Microscope Slides Preparartion
Tissue Preparation For Microscpy
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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INTRODUCTION
Classification of Microorganisms
Bacteria
Classification of Bacteria
Nutrition in Bacteria
Reproduction in Bacteria
Economic Importance of Bacteria
Fungi
Classification of Fungi
Nutrition in Fungi
Reproduction In Fungi
Economic Importance of Fungi
Virus
Classification of Virus
Reproduction in Virus
Economic Importance of Virus
Culture Media
Preparation of Culture Media
Culture Methods
Culture Techniques
Microbiological Stains and Staining Techniques
Microbiological Staining Techniques
Sterilization
Chemicals of Life
THE CHEMICALS OF LIFE OBJECTIVES By the end of this topic, the trainee should be able to: 1.Explain meaning of terms. 2.Describe chemical substances found in living organisms. 3.Describe the functions of substances found in living organisms. 4.Describe enzymes. 5.Carry out food tests.
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INTRODUCTION
Carbohydrates
Structural composition of Carbohydrates
Chemical Tests for Carbohydrates
Lipids
Structural composition of Lipids
Saturated and Unsaturated fats
Tests for Lipids
Proteins
Structural composition of Proteins
Protein Denaturation
Properties of Proteins
Test for Proteins
Nucleic Acids
Vitamins
Enzymes
Classification of Enzymes
Mechanisms of Enzyme Action
Factors Affecting Enzyme Activities
Enzyme Inhibition
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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INTRODUCTION
Types of Immunity
Lymphocytes and Lymphatic System
The White Blood Cells  (Leucocytes )
Lymphoid Organs ,Tissues and Immune Cells
Immunoglobulins
Antigens
Immunological Techniques
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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Introduction
Collection of Plant Specimens
Collecting techniques
Preservation Techniques
Processing of Specimens
Storage of Specimens
Pests In The Herbarium
Green House and Botanical Garden
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
INTRODUCTION
Collection of Museum Specimens
Preservation of Museum Specimens
Preservation of other animals specimens
Labeling of museum specimens
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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Introduction
Setting Up A vivarium
Ecological Requirements
Care and Handling
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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Introduction
Setting up an Aquarium
Basic Physical and Ecological requirements
Feeding and General care of Aquarium
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
General Care of Laboratory Animals
Laboratory Animal House
Feeding of Laboratory Animals
Disease and Disease control in Laboratory animals
Sexing of Laboratory Animals
Identification of Laboratory Animals
Dosing of Laboratory animals
Drawing blood from Lab animals
Administering anesthesia to laboratory animals
Humane Killing of Laboratory Animals
Dissecting Laboratory Animals
Conventional and Specific Pathogen free animals
Gnotobiotic Animals
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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Introduction
The Biosphere and Biomes
The Ecosystem
Energy Flow
Estimation of Population size
Nutrient Flow in Ecosystem
Water cycle
Carbon Cycle
Nitrogen Cycle
Sulfur Cycle
Phosphorous Cycle
Ecological succession
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 .
0/9
INTRODUCTION
Plant Vascular Tissues
Plant Leaf Structure
Transport of substances into and out of the leaf 
Nutrition in Plants
Transpiration in Plants
Translocation in plants
Reproduction in Plants
Excretion in Plants
Animal Anatomy and Physiology
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Describe of animal parts and tissues. 2.Describe functions of various animal tissues and organs. 3.Describe physiological processes in animals .
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Nutrition In Animals
Types of Nutrition  in Animals
Digestion in Humans
Digestion in Ruminants
Respiration in Animals
Modes of Gaseous Exchange in Animals
Mammalian Respiratory System
Excretion in Animals
Excretion in Higher Animals
Excretory System in Man:
Transport In Animals
Circulatory systems in animals
Human circulatory systems 
The cardiac cycle 
The Blood Vessels
Lymphatic circulatory system
Cardiovascular diseases 
Support and Locomotion system in Animals
Exoskeleton and Endoskeleton
Human Skeleton
The Bones 
Musculoskeletal tissues 
The Nervous System
The Nerve Tissue
Organization of the Nervous System
Reproductive system in Animals
Male Reproductive System
Female Reproductive System
The Endocrine System
Endocrine Glands & Their Hormones
Biology Techniques For Science Laboratory Technicians
About Lesson

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The cardiac cycle 

A cardiac cycle refers to the sequence of events that happens in the heart from the start of one heartbeat to the start of the subsequent heartbeat. During a cardiac cycle the atria and the ventricles work separately. The sinoatrial node (pacemaker) is located in the right atrium and regulates the contraction and relaxing of the atria.

  • At rest, each heartbeat takes approximately 0,80,8 seconds.
  • The normal heart rate at rest is approximately 7272 beats per minute.
  • During systolethe heart muscle contracts.
  • During diastolethe heart muscle relaxes.

The phases of the cardiac cycle will be broken down and explained in the following section:

Phase 1: Atrial systole (Atrium contracts)

  • Blood from the superior and inferior vena cava flows into the right atrium.
  • Blood from the pulmonary veins flows into the left atrium.
  • The atria contract at the same time.
  • This contraction lasts for about 0,10,1 seconds.
  • Blood is forced through the tricuspid and bicuspid valves into the ventricles.

Phase 2: Ventricular systole (Ventricle contracts)

  • Ventricles relax and fill with blood.
  • The ventricles contract for 0,30,3 seconds.
  • Blood is forced upwards, closing the bicuspid and tricuspid valves (lubb sound).
  • The blood travels up into the pulmonary artery (on the right) and the aorta (on the left).
  • The atria are relaxed during ventricular systole.

Phase 3: General diastole: (General relaxation of the heart)

  • The ventricles relax, thus decreasing the flow from the ventricles.
  • Once there is no pressure the blood flow closes the semi-lunar valves in the aorta and the pulmonary artery (dubb sound).
  • General diastole lasts for about 0,40,4 seconds.

The sound the heart makes

The heart makes two beating sounds. One is loud and one is soft. We call this the lubb dubb sound. The lubb sound is caused by the pressure of the ventricles contracting, forcing the atrioventricular valves shut. The dubb sound is caused by the lack of pressure in the ventricles which causes the blood to flow back and close the semi-lunar valves in the pulmonary artery and aorta. A doctor uses a stethoscope to listen to the heartbeats. Alternatively, a person’s pulse can be measured by pressing a finger (other than the thumb which already has a pulse) against the brachial artery in the wrist or the carotid artery next to the trachea. The pulse of the heart allows us to measure the heart rate which is the number of heartbeats per unit time.

Mechanisms for controlling cardiac cycle and heart rate (pulse)

The cardiac cycle is controlled by nerve fibres extending from nodes of nerve bundles through the heart muscle. There are two nodes, namely the sinoatrial node (SA node) and the atrioventricular node (AV node). The SA node is located within the wall of the right atrium while the AV node is located between the atria and the ventricles. Electrical impulses generated in the SA node cause the right and left atria to contract first, initiating the cardiac cycle. The electrical signal reaches the AV node, where the signal pauses, before spreading through conductive tissues called the bundles of His and Purkinje fibres. These fibres branch into pathways which supply the right and left ventricles, causing the ventricles to contract. The SA node is the pacemaker of the heart since electrical signals are normally generated there – without any stimulation from the nervous system (automaticity). However, although the heart rate is automatic, it changes during exercise or when experiencing intense emotions like fear, anger and excitement. This is as a result of added stimulation from the nervous system and hormones, such as adrenaline.

Electrical activity

The electrical activity in the heart is so strong that it can be measured from the surface of the body as an electrocardiogram (ECG). A normal heart has a very regular rhythm. Arrhythmia is a condition where the heart has an abnormal rhythm, as shown in the figures. Tachycardia is when the resting heart rate is too fast (more than 100100 beats per minute), and bradycardia is when the heart rate is too slow (less than 6060 beats per minute).

Figure 7.8: Electrocardiogram depicting different heart rhythms.

Stroke Volume

The stroke volume is the amount of blood pumped through the heart during each cardiac cycle. The stroke volume can change depending on the needs of the body. During exercise, muscles need more oxygen and glucose in order to produce energy in the form of ATP. Therefore the heart increases its stroke volume and stroke rate to meet this demand. This is a temporary change to maintain homeostasis, and after exercise the heart rate and stroke volume return to normal.

When a person exercises regularly, and is fit, the heart undergoes certain long-term adaptations. The heart muscle gets stronger, and expels more blood with each contraction. There is therefore a greater stroke volume with each heartbeat. Since the heart expels more blood with each stroke, the heart has to beat less often in order to maintain the same volume of blood flow. Therefore, fit people often have lower resting heart rates. Cardiac output is the volume of blood that is pumped by the heart in one-minute. Cardiac output is equal to the stroke volume (SV) multiplied by the heart rate (HR)

.Blood Pressure

Blood pressure refers to the force that the blood exerts on the blood vessel walls. Blood pressure is determined by the size of the blood vessels and ensures that blood flows to all the parts of the body. Normal blood pressure is 120/80 (120 over 80) measured in units of mercury (mm Hg). The 120 represents the systolic pressure, which is when the ventricles contract. The 80 represents the diastolic pressure, which is when general diastole occurs.

Blood pressure can be increased by smoking, stress, adrenalin surges, water retention, high cholesterol, obesity and lack of exercise. High blood pressure (hypertension) is dangerous and increases the risk of an aneurysm, stroke or heart attack. Low blood pressure (hypotension) can lead to light-headedness and fainting because of insufficient blood supply to the brain.

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