Staphylococcus and Streptococcus Tests
Coagulase Test
Coagulase is an enzyme capable of converting fibrinogen to fibrin, causing visible clot formation in a suitable analytical system. A positive reaction is shown by the formation of a clot or gel. Staphylococcus aureus bacteria are coagulase-positive.
Glucose Fermentation Test
This test can differentiate the genus Micrococcus from the genus Staphylococcus because the latter gives a positive test result.
Mannitol Fermentation Test (1%)
Strains of S. aureus, in contrast to those of S. epidermidis,
Read MoreRespiratory, Circulatory, and Excretory Systems
Respiratory System
The respiratory system contains the airways and lungs. Its function is to capture the oxygen that our body needs and to expel the carbon dioxide produced.
- Respiratory: nasal cavities, pharynx, larynx, trachea, and bronchi.
- Lungs: two elastic, fluffy, pink bodies occupying almost the entire chest.
- Ribcage: This includes the spine, ribs, diaphragm, and sternum.
Respiratory Diseases
- Microorganisms:
- Cold and flu: virus.
- Pharyngitis, laryngitis, bronchitis, and pneumonia: Inflammation.
- Inhaling
Gene Expression and Genetic Transfer in Bacteria
Transcription and Translation in Gene Expression
Transcription and translation are two key processes in gene expression, where the information in a gene is used to produce a functional product, typically a protein.
Transcription
- Initiation: The process begins when RNA polymerase binds to a specific region of the DNA called the promoter, signaling the start of a gene.
- Unwinding: The DNA double helix unwinds, exposing the template strand of the DNA that will be used to synthesize RNA.
- Elongation: RNA polymerase
Protein Properties, Functions, and Classification
Properties of Proteins
Proteins’ properties depend mainly on the nature of their amino acids. These properties include:
Behavior and Chemical Solubility
Proteins, like amino acids, are amphoteric substances. This means they can buffer pH variations. Their solubility depends mainly on their conformation. Generally, fibrous proteins are insoluble, and globular proteins are water-soluble. However, due to their high molecular mass, they form colloidal dispersions. Nonpolar amino acids are located inside
Read MoreLevels of Biological Organization: Bioelements & Biomolecules
Levels of Biological Organization
Subatomic Level: Includes subatomic particles that make up atoms (electrons, protons).
Atomic Level: Includes atoms that constitute our body. A bioelement is the set of atoms of the same type.
Molecular Level: Includes molecules and clusters of molecules, such as the cell membrane, composed of various types of cellular molecules.
Cellular Level: Includes cells and multicellular organelles.
Tissue Level: The level of organization of multicellular individuals, including
Read MoreUnderstanding the Digestive Process: Stages and Mechanisms
Understanding the Digestive Process
The digestive process encompasses all the steps involved in breaking down food within the digestive tract for assimilation.
Stages of Digestion
- Ingestion: This is the entry of food into the organism. Most animals have specialized structures in the mouth to facilitate the capture and ingestion of food.
- Digestion: This converts food into simpler molecules that cells can use. In most animals, food undergoes both mechanical and chemical transformation.
- Absorption: The