Page 21 – Biology Notes Online

Culture Media – Definition, Types, Composition, Use, Examples

• Published on January 21, 2025 • 31 min readby Editorial Team

When it comes to culturing bacteria, it is crucial to create the same environmental and nutritional conditions as those found in the natural environment. The majority of culture mediums contain water, which is a major source of carbon and energy and nitrogen. It also contains trace elements, as well as some growth factors. In addition, the pH as well as oxygen tension and Osmolarity must also be considered. Some of the components of media for culture include: Although tap water is appropriate for the use of culture media, it shouldn’t be used in the event that it contains a significant amounts of minerals. In these instances the use of demineralised or distillated water is recommended.

Classification of Bacteria Based on Cell Wall, pH, Temperature, salt, Nutrition, Oxygen, Shape

• Published on January 21, 2025 • 23 min readby Editorial Team

Little, single-celled creatures living practically everywhere are bacteria. They’re prokaryotic, meaning they lack a real nucleus. They differ from eukaryotic cells in that they lack membrane-bound organelles. Shapes vary; spherical (cocci), rod-like (bacilli), spiral (spirilla), or comma-shaped (vibrios). Their survival in hostile environments depends on this diversity. Some twist like corkscrews, designated as spirochaetes. There … Read more

Benedict’s Test – Principle, Reagents, Procedure, Result, Limitation

• Published on January 20, 2025 • 17 min readby Editorial Team

Benedict’s Test - Principle, Reagent Preparation, Procedure, Result, Limitation

Benedict’s test is a chemical test that is used to test for the presence of reduced sugars within an analytical test. Thus, simple carbohydrates that contain an aldehyde or free ketone functional group are detected using this test. The test is basing itself upon Benedict’s Reagent (also called Benedict’s solution) which is a complex mix of sodium carbonate, sodium citrate, and the pentahydrate of copper(II) Sulfate.

What is Semiconductor Sequencing? – Principle, procedure, uses

• Published on January 19, 2025 • 10 min readby Sourav Pan

What is Semiconductor Sequencing? Semiconductor sequencing is the integration of microchip technology with DNA sequencing where electrical signals replace the detection of light. This sequencing method is unique because it uses complementary metal-oxide semiconductor chips associated with sequencing by synthesis chemistry; so, in this respect, it opens up opportunities to make DNA analysis quicker and … Read more

Trinocular Microscope – Definition, Principle, Parts, Protocol, Uses

• Published on January 19, 2025 • 24 min readby Editorial Team

What is Trinocular Microscope? Principle of Trinocular Microscope A trinocular microscope is similar to a binocular microscope but has an additional third eyepiece for a camera. It shines an LED light on the specimen and projects it onto a computer screen through a digital camera. The trinocular microscope is essentially a binocular microscope that focuses … Read more

Thyroid Gland – Structure, Hormones, Functions, Disorders

• Published on January 17, 2025 • 31 min readby Sourav Pan

What is Thyroid Gland? Definition of Thyroid Gland The thyroid gland is a butterfly-shaped endocrine organ located in the anterior neck that produces hormones such as thyroxine (T4), triiodothyronine (T3), and calcitonin, which regulate metabolism, growth, and calcium homeostasis. It plays a crucial role in maintaining the body’s metabolic rate and overall hormonal balance. Anatomical … Read more

Rickettsia Infection – Transmission, Diagnosis, Pathogenesis, Treatment

• Published on January 16, 2025 • 22 min readby Editorial Team

Rickettsia Infection - Tick-Borne Rickettsioses And Spotted Fever

What is Rickettsia? Small-sized intracellular bacteria with a 0.3 to 2 µm range make up the genus Rickettsia. Rickettsia’s tiny scale made it first confused as a virus. Having DNA and RNA as their genetic material, these bacteria reproduce via binary fission within the cytoplasm of eukaryotic cells. Gram-negative rickettsia bacteria abound in the digestive … Read more

Urinary Tract Infection (UTI) – Pathogenesis, Treatments, Diagnosis, Prevention

• Published on January 16, 2025 • 16 min readby Editorial Team

Treatment of Urinary Tract Infections with D-Mannose

What is Urinary Tract Infection (UTI)? An illness affecting a portion of the urinary tract—that which comprises the kidneys, ureters, bladder, and urethral—is known as a urinary tract infection (UTI). Following are some salient features of urinary tract infections: Types of Urinary Tract Infection (UTI) UTIs can attack various urinary system segments, causing varied symptoms. … Read more

Electron Microscope – Principle, Types, Parts, Application, Diagram

• Published on January 16, 2025 • 34 min readby Editorial Team

An electron microscope is an instrument which produces an image of a sample by means of a beam of electrons. Optical microscopes use light to form an image, electron microscopes have greater resolution, and can be used to observe objects that are too small to be seen with an optical microscope. In a large variety … Read more

Cryo Electron Microscopy – Principle, Procedure, Advantages, Limitations and Applications

• Published on January 15, 2025 • 17 min readby Sourav Pan

Cryo Electron Microscopy - Principle, Strengths, Limitations and Applications

What is cryo-EM? Principle of cryo EM Types of cryo EM Cryo-electron microscopy (cryo-EM) is a collection of special methods. These are broadly categorized into two types, mainly cryo-transmission electron microscopy (cryo-TEM) and cryo-scanning electron microscopy (cryo-SEM). Each has its own advantage in the analysis of biological samples in their native state, frozen by cryo-preparation. … Read more