Vorticella (L.,vortex=whirl pool) is a microscopic, unicellular eukaryotic ciliate. It occurs as a sessile attached by a stalk to the substratum. Its body is almost bell-shaped or campanulate with a free anterior end surrounded by cilia. The commonest species is Vorticella campanula. Some of the species included in this genus … Read more
Aurelia is commonly referred to as jellyfish because it is made of a jelly-like substance. A jellyfish is not true fish which is a vertebrate animal with a backbone. It belongs to the class Scyphozoa of phylum Coelenterata. The most common scyphozoan jellyfish is Aurelia aurita (popularly known as moon … Read more
We know Arthropoda is the largest phylum, with the highest number of species, and the numbers of individuals are also high. So Arthropods have various types of respiratory systems, some of them described below : 1- Tracheal system 2- Book-lungs 3- Blood-gills 4- Gills 1. Tracheal Respiratory system It is … Read more
Metabolism involved biological reactions and non-biological reactions which need organisms to lives life. Metabolism includes the conjugation, reduction, dehydroxylation, cyclization, methylation, phosphorylation, and oxidation of substrates (beta-oxidation of fatty acid, glucose, etc.) and the liberation of energy, heat, and carbon dioxide. Metabolism is considered as: Primary metabolism: Primary metabolism is … Read more
Euglena viridis (Gr.,eu, true+ glene, eyeball or eye pupil+L., Viridis, green) is a unicellular green organism with an eye-like photoreceptive structure. It is phytoflagellate as it possesses both chloroplasts as well as flagella. It is autotrophic in sunlight but becomes heterotrophic in dark. Systematic position Phylum: Protozoa Subphylum: Sarcomastigophora Superclass: … Read more
Medical Disclaimer: The information presented on this page is only for academic and study purposes and must not be used for the purpose of treatment. If you are not feeling well, please consult with your physician or doctor. Pharmacology features among science courses, specializing in drugs and how they interact … Read more
Hormones of Insects Body Although hormones are mainly present in chordates, yet some hormones are also present in arthropods, that is insects. There are various hormones secreted in insects, which play role in metamorphosis. Some of the hormones are as follows. 1- Brain hormone (BH) The brain has neurosecretory cells. … Read more
What are Nematodes? The word nematode is derived from Greek words- Nema meaning “thread” and oids meaning “resembling or forms”. Nematodes are also known by different names such as threadworms, roundworms, eelworms, and nema. Nematodes constitute the largest group of an animal kingdom comprising 80-90% of all multicellular animals. These … Read more
Microbial Genetics Genetics: is the science that studies the inheritance of biological characteristics by living things. This subject, also known as heredity, is a wide-ranging science that examines: The transmission of biological properties (traits) from parents to offspring. The expression and variation of those traits. The structure and function of … Read more
Immune Response is a mechanism of how the immune system of the host’s body responds to a harmful foreign particle or pathogen (antigen) in the body. It entails recognizing the antigen and eliciting mechanisms to defend itself from foreign pathogens. Immune responses are induced as a means of protection from … Read more
Strongyloides stercoralis is a parasitic roundworm that causes strongyloidiasis. It is commonly called a threadworm in the US. It is the smallest nematode known to cause infection in humans. They are unique among nematode because it has both parasitic and free-living form. Image Source: The Australian Society for Parasitology and CDC. … Read more
Edible Vaccines WHAT IS VACCINE? The vaccine is a biological preparation that improves immunity against a particular disease. It contains an agent that resembles a disease-causing microorganism and is often made from a weakened or killed form of microbe, its toxins or one of its surface proteins. The agent stimulates … Read more
Fasciola hepatica is also known as a common liver fluke or sheep liver fluke. It causes hepatic fibrosis in ruminants and humans known as Fascioliasis. History and distribution of Fasciola hepatica Fasciola hepatica was the first fluke or trematode that was discovered more than 600 years ago in 1379 by … Read more
Citric Acid Production INTRODUCTION Citric acid is the most important commercial product which is found in almost all plant and animal tissues. The molecular formula of citric acid is C6H8O7, 2-hydroxy-1,2,3-propane tricarboxylic acid. It is widely used organic acid in the field of food (60%) and pharmaceuticals (10%). In 1784 … Read more
Biofertilizer- Types and Uses Biofertilizer is a substance which contains living microorganisms which, when applied to seeds, plant surfaces, or soil and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Biofertilizers add nutrients through the natural processes of nitrogen fixation, solubilizing phosphorus, and stimulating plant … Read more
Ammonia is a toxic product to the body of animals, thus ammonia is continuously excreted from the body of the animals, in various from depending upon the external environment and physiology of animals. Types of animal-based on excretion of nitrogenous waste There are different types of nitrogenous waste products in … Read more
What is Mucormycosis? Mucormycosis is an infection caused by several species of filamentous molds belonging to the order Mucorales. The infections usually occur in immunocompromised individuals with one or more underlying conditions. The fungi responsible for these infections are found in different environmental niches like soil, decaying vegetables, bread, and … Read more
For examination in June and November 2022, 2023, and 2024. Image Credit: Cambridge Assessment International Education. Candidates for Cambridge International AS Level Biology study the following topics: 1. Cell structure 1.1 The microscope in cell studies 1.2 Cells as the basic units of living organisms cell surface membrane nucleus, nuclear … Read more
Benedict’s test for reducing sugars Definition Benedict’s test is a biochemical test performed to distinguish reducing sugars (monosaccharides and some disaccharides) from non-reducing sugars. Objectives To detect the presence of simple carbohydrates in a solution. To distinguish between reducing and non-reducing sugars. Principle The carbohydrates having a free or potentially … Read more