CONTENT: Structure of fruits Types of fruits Dispersal of fruits Agents of dispersal MEANING OF FRUIT Fruit is the structure that developed from the matured ovary after fertilization which…

Lessons
Variation and Evolution
CONTENT: Morphological variations Physiological variation Application of variation INTRODUCTION Evolution is the cumulative changes in the characteristics of population or organisms occurring in the course of successive generations related…
Biology of Heredity: Genetics
CONTENT: Transmission and expression of characters in organisms Chromosomes the basis of heredity. Probability in genetics. Applications of principles of heredity Explanation on cross and self fertilization INTRODUCTION TO…
Evolution
CONTENT: Progressive change in structure and anatomy of organisms. Structural adaptation: Adaptive colouration. Structural adaptation: For obtaining food. Different castes of termites. Different castes of bees. PROGRESSIVE CHANGE IN…
SS3 Biology First Term Examination
Balance in Nature
CONTENT: Factors affecting a population Dynamic population Family planning FACTORS AFFECTING A POPULATION In ecology, the interaction between plant and animals in an environment produces a stable and a…
Reproductive Systems and Reproduction in Humans
CONTENTS A. Reproductive system in males and female Function of various parts Structure of a male sperm and ovum B. Fertilization Fusion of gametes Implantation C. Development of embryo Selective…
Development of New Seeds
CONTENT: Progress of development of zygote in the flowering plant Germination of seeds PROGRESS OF DEVELOPMENT OF ZYGOTE IN THE FLOWERING PLANT Meaning of seed Seeds are plant parts…
Sense Organs: The Organ of Hearing and Balance
In vertebrates, the two ears perform the functions of hearing and balancing. The ear of man is located in the temporal bone on the skull. The ear has three distinct…
Evolution: Theories of Evolution; Evidence of Evolution
CONTENT: Theories of Evolution. The theories of evolution according to Charles Darwin, Jean Baptist de Lamark Evidence of evolution. Forces responsible for evolution: mutation, gene flow, genetic drift. INTRODUCTION…
Sense Organs: Organ of Smell
SENSE ORGAN – THE NOSE THE ORGAN OF SMELL The nose (olfactory organ) is the organ of smell. It consists of groups of chemo receptors found in the epithelial lining…
Sense Organs: Organ of Taste
THE ORGAN OF TASTE In mammals the organ of taste is the tongue. Taste chemoreceptors are grouped on the upper surface of the tongue, on the soft palate and in…
Sense Organs: Organ of Touch
THE SKIN The sensations of touch, pressure, pain, cold and heat are detected by the mammalian skin which is richly supplied with sensory receptors. The sensory receptors in the skin…
Ecology of Population I
CONTENT: 1. Succession (i) Meaning of succession (ii) Structural changes in species composition, variety and increase in number. (iii) Primary succession (a) Aquatic and (b) Terrestrial habitat (iv) Secondary succession-Meaning…
Ecology of Population II
CONTENT: 1. Relationship between succession and competition. 2. Factors that may cause overcrowding. 3. Measures adapted by nature to avoid overcrowding e.g. (i) Dispersal of seeds and fruits (ii) Migration…
Sense Organs: Organ of Sight
SENSE ORGANS Information about the mechanical, thermal, chemical and electromagnetic changes in the internal and external environment are perceived by sensory receptors in our bodies. These process the information and…
Reproductive Behaviours in Animals
CONTENT: Paring Territoriality Display of body colours Seasonal migration COURTSHIP BEHAVIOURS IN ANIMALS Courtship is a collection of ritualized behaviours unique to each species that lead up to and…