Life science microbiology

• HIV treatment reduces the amount of HIV (viral load) in your body and helps you stay healthy and reduce the risk of transmitting the virus to others.
• Viruses are tiny (10 -200 nm) pathogens, half a million would fit onto a full stop.
• Viruses can only be seen with an electron microscope, they were first seen in the 1930s with an electron microscope.
• Viruses are measured in nanometers (nm).
• Viruses are Acellular, not made up of a cell or cells, and do not belong to any of the eukaryotic or prokaryotic domains.
• Viruses are considered nonliving, they cannot perform any life processes such as respiration, excretion, nutrition, growth and response to stimuli.
• Viruses reproduce inside a living host, they are intracellular parasites.
• Viruses are Obligate parasites, they need a host’s cell to reproduce, by replication.
• Viruses are Pathogenic, they cause disease.
• Viruses are Host specific, they are species and cell specific.
• Virus particles (known as virions) consist of 2 or 3 parts: a core of genetic material made from either DNA or RNA, a protein coat that protects the genetic material (capsid), and in some cases an envelope of lipids that surrounds the protein coat when they are outside a cell.
• Genetic material or Nucleic acid in viruses provides genetic information (genes) to make it possible to synthesise all proteins and helps synthesise new viruses within the host cell.
• The capsid in viruses protects the nucleic acid from being digested by host enzymes and contains unique sites on its surface that allow the virus to attach to a host cell.
• The lipid envelope in viruses contains special structures called spikes made of glycoproteins and helps with the entry of virus into host cell by attaching to specific host-cell surfaces using the spikes.
• Viruses are Specific, different cell types have different proteins on their surface, which viruses can bind to.
• Viruses cannot infect any cell, for example, COVID cannot infect fungi or plant cells; the flu can only infect cells of your respiratory system.
• In the case of COVID, its spike protein bonds to the ACE2 protein of your respiratory cells.
• Many new mature viruses accumulate within the host cell, and the host cell ruptures (lysis) to release the viruses within it.
• Lysis is the breaking down of the membrane of a cell.
• Rotavirus and Norovirus are common causes of viral gastroenteritis, which are transmitted by the faecal-oral route and are passed from person to person by contact, entering the body in food or water.
• HIV, or Human Immunodeficiency Virus, is a virus that attacks the immune system, specifically the CD4 cells (T cells), which help the immune system fight off infections.
• Influenza virus, Coronavirus, 2019 Novel Coronavirus, Measles Virus, and HIV are examples of complex viruses with a large variety of components in their capsids.
• A virus only contains a few genes to make copies of itself: genes for structural proteins and genes for enzymes used during the viral cycle.
• Symptoms in the first few weeks after being infected with HIV include fever, headache, rash, sore throat, and flu-like symptoms.
• Some replicate by injecting their DNA into the host cell.
• A virus enters a host cell by endocytosis and uses the host’s nucleic acid to make more (replicate) of its own nucleic acid.
• Many viruses exhibit a morphology that is common and a structural feature.
• The range of host cells that a virus can infect is called its 'host range'.
• HIV is transmitted through sexual contact and by exposure to infected blood.
• If left untreated, HIV can lead to the disease AIDS (Acquired Immunodeficiency Syndrome).
• There is no cure for HIV, but you can control it with HIV treatment, which involves taking medicine as prescribed by a health care provider.
• Viruses do not have genes for replication, and genes for replication, enzymes required for protein synthesis, and energy production are supplied by the host cell.
• Viruses spread in many ways: through plant sap, by blood-sucking insects, coughing and sneezing, the faecal-oral route, and sexual contact.
• Helical viruses have the viral nucleic acid coil into a helical shape and the capsid proteins wind around the the nucleic acid, forming a long tube or rod-like structure.
• Polyhedral viruses have nucleic acid encased in a polyhedral (many-sided) shell or capsid.
• Spherical viruses are a type of virus that has a spherical or roughly spherical shape.
• Microbiology is the study of all living organisms that are too small to be seen with the naked eye, including bacteria, viruses, fungi, protozoa and algae, collectively known as microorganisms or microbes.
• Microorganisms are microscopic organisms which means that they are too small to be seen with the naked eye.
• A microbiologist is a scientist who studies microscopic organisms or microorganisms.
• Microbiology includes the study of microorganisms that are Acellular (no cell membrane) such as viruses, and Cellular Prokaryotes (nuclear material not enclosed in a membrane) like Bacteria.