Course Content
Introduction to Biology
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Introduction
Characteristics of Living Organisms
Collection, Preservation and Observation of Specimens
Classification I
The Cell
Cell Physiology
Nutrition in Plants and Animals
Transport in Plants and Animals
Gaseous Exchange
Respiration
Excretion and Homeostasis
Classification II
Ecology
Reproduction in Plants and Animals
Growth and Development in Plants and Animals
Genetics
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Introduction to Genetics
Terminology used in Genetics
Variations
Sample Questions
Chromosome
Cell Division
Gene and DNA
DNA Replication
Role of DNA in Protein Synthesis
Differences DNA and RNA
The First Law of Heredity
Types of Dominance
Complete dominance
Incomplete dominance
Codominance
Inheritance of ABO Blood Groups
Inheritance of Rhesus Factor
Determining Unknown Genotypes
Sex Determination
Linkage
Sex-linked genes
Colour Blindness
Haemophilia
Hairy pinna
Secondary sexual characteristics
Effects of Crossing Over on Linked Genes
Mutations
Chromosomal Mutations
Gene mutation
Disorders due to Gene Mutations
Albinism
Sickle-cell Anaemia
Haemophilia
Colour blindness
Effect of Environment on Heredity
Practical Applications of Genetics
Evolution
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Introduction to Evolution
Chemical Evolution
Evidences of Organic Evolution
Fossil Records
Geographical Distribution of Living Organisms
Comparative Embryology
Comparative Anatomy
Cell Biology
Comparative Serology
Mechanisms of Evolution
Lamarck’s Theory (Use and Disuse)
Darwin’s Theory of Natural Selection
Natural Selection in Action
Role of mutations in evolution
Reception, Response and Coordination in Plants and Animals
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Introduction
Types of Responses to a variety of Stimuli
Taxis/Tactic Response
Tropisms
Comparison of Tropic and Tactic Responses
Nastic Responses
Coordination in Plants
Role of Auxins in Tropisms
Etiolation
Reception, Response and Coordination in Animals
Nerve Cells (Neurones)
The Central Nervous System
Functions of Major Parts of the Brain
SPINAL CORD
Reflex Action
Transmission of Nerve Impulse
Synapse or Neuro-junction
Impulse transmission across the synapse
The Endocrine System
Thyroxine and Adrenaline
Comparison between Endocrine and Nervous Systems
Drug abuse and the effects of Drug abuse on Human Health
Sense Organs
The Eye
Structure and Function of parts of the human eye
Cones and Rods
Adaptations of the Eye to its function
Image Formation and Interpretation
Support and Movement in Plants and Animals
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Introduction
Necessity of Support and Movement of Plants and Animals
SUPPORT IN PLANTS
Support tissues in plants
Support tissues in plants (summary)
Types of Stems
SUPPORT AND MOVEMENT IN ANIMALS
Locomotion in a Finned Fish
Support and Movement in Mammals
The Skull
The Ribcage and Sternum
The Vertebral Column
The Cervical Vertebrae
Thoracic vertebrae
The Lumbar Vertebrae
The Sacral Vertebrae
The Caudal Vertebrae
The Appendicular Skeleton
Humerus
Ulna and Radius
Carpals, Metacarpals and Phalanges
The Pelvic Girdle
The Femur
Adaptations of bones to their function
Joints
Movable Joints
Movement at a Joint
Muscles
Final Exam
BIOLOGY

DNA Replication

The DNA double helix consists of two long separate strands joined together by the base pairs. When the molecule is due to replicate the double helix unwinds and the two stands unzip themselves. This is made possible by the presence of the weak hydrogen bonds that link the bases of the two strands. Unzipping is therefore as a result of breaking of the hydrogen bonds thus setting each strand free from the other. After unzipping, the information on the DNA strands, that is the base sequence, is copied out onto a new DNA structure using the parent DNA as the template and thus, the parent molecule is said to have  replicated itself.  The replication makes it possible to pass on the DNA molecule together with its exact genetic information to daughter cells during cell division in the organism.

DNA replication
DNA replication

As the cell prepares for division during interphase, genetic material (DNA) replicates i.e. doubles itself so that sufficient DNA is made available for each of the daughter strands.

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