Welcome to Biology Notes Online! We are the BNO Team, dedicated to providing high-quality, accessible biology study notes for students and teachers alike. Our goal is to simplify complex biological concepts and present them in an easy-to-understand format, entirely free of charge. Whether you're preparing for exams, teaching a class, or simply passionate about biology, our comprehensive notes are designed to support your learning and teaching journey.
What is Gene frequencies? Gene frequencies, also known as allele frequencies, refer to the relative proportions of different alleles at a particular locus or gene within a population. They represent the prevalence or abundance of specific alleles in relation to the total number of alleles in the gene pool. Gene frequencies are typically expressed as … Read more
The concept of species has been a subject of ongoing debate and controversy among taxonomists and biologists. The task of defining and recognizing species is crucial for understanding the diversity and organization of life on Earth. Over time, various species concepts have been proposed to tackle this challenge, each with its own merits and limitations. … Read more
What is Macroevolution? Definition of Macroevolution Macroevolution refers to the large-scale evolutionary changes that occur above the level of species, involving the emergence of new taxa (genera, families, orders, etc.) and the diversification of life forms over long periods of time. It encompasses the study of patterns and processes that shape the biodiversity and relationships … Read more
What is Extinction? What is Background extinction? Factors Involved in Background Extinction Background extinction, the natural rate of species loss throughout Earth’s history, is influenced by various factors that shape the delicate balance of ecosystems. While not as sensational as mass extinctions, background extinction occurs gradually as species struggle to adapt to environmental changes. Understanding … Read more
Origin and Evolution of Man Features of Man The evolution of humans has brought about several distinctive features that set them apart from other primates. These progressive features have contributed to the unique characteristics and capabilities of human beings. Let’s explore these features in more detail: One of the most remarkable features distinguishing humans from … Read more
What is Biological Clocks? Types of biological clocks There are several types of biological clocks found in living organisms. Here are some of the major types: It’s important to note that different organisms may have different types of biological clocks or variations of these clocks based on their specific ecological and physiological requirements. The study … Read more
Historical Overview Throughout human history, the origin of life has captivated our curiosity and inspired various creation myths involving supernatural forces. However, ancient Greek thinkers were the first to approach the topic from a scientific standpoint, proposing the concept of spontaneous generation as a mechanism for complex organic forms to arise from simpler inorganic matter. … Read more
What is Lamarck’s Theory? Postulates of Lamarckism’s Theory Lamarckism, formulated by Jean-Baptiste de Monet Lamarck, is based on four fundamental postulates that form the core of his evolutionary theory: Lamarck’s theory can be summarized by four main propositions: While Lamarckism has been largely superseded by modern evolutionary theory, it played a significant role in shaping … Read more
What is Darwinism Theory? The Theory of Evolution – Darwinism Theory The Theory of Evolution, formulated by Charles Darwin in the mid-19th century, is a scientific explanation for the diversity of life on Earth. It is considered one of the most important and well-supported scientific theories in the field of biology. At its core, the … Read more
What is Neo-Darwinism Theory? Neo-Darwinism is an integration of Charles Darwin’s theory of evolution by natural selection with Gregor Mendel’s theory of genetics. It arose from the recognition that Darwin had not adequately explained the existence of variations within species. In 1901, the Dutch botanist Hugo de Vries proposed the mutation theory of evolution, which … Read more
⚠️
Click on your ad blocker icon in your browser's toolbar
Select "Pause" or "Disable" for this website
Refresh the page if it doesn't automatically reload