PROTEIN SYNTHESIS DNA is the molecule that carries instructions for our development. The genetic code is the sequence of nucleotides and amino acids in a polypeptide chain. DNA is a polynucleotide made up of nucleotides containing deoxyribose (a sugar), a phosphate...
FORENSICS Investigating time of death: As soon as a person dies, chemical changes occur in order, so can be used to estimate the time of death. Rigor mortis/degree of muscle contraction: · Begins when muscle cells become deprived of oxygen · ...
BACTERIA AND VIRUSES Infectious diseases are mostly caused by bacteria and viruses. Bacteria: Useful bacteria are found on the skin and in the digestive tract Prokaryotic cellular structure, single celled organelles Prokaryotic cells store carbon compounds in the form...
BARRIERS TO PATHOGEN ENTRY Pathogens enter through areas not covered by skin – nose, mouth, eyes, gas exchange surfaces, gastrointestinal tract and genital tract and through wounds. Eyes, nose, mouth: Tears contain the enzyme lysozyme which helps to digest microbes –...
NON SPECIFIC RESPONSE Inflammation: At the site of infection, damaged white blood cells and mast cells release histamines that cause arterioles to dilate and capillaries to become more permeable. Blood flow to the area increases and plasma, white blood cells and...
SPECIFIC RESPONSE Relies on lymphocytes which respond to foreign antigens on the surface of bacteria and viruses Can take two forms – Humoral response (B cells) and cell mediated response (T cells) Humoral response Has two main stages Pathogen with antigens on...
TYPES OF IMMUNITY Immunity is the ability of microorganisms to resist infection by protecting against disease causing microorganisms. When the body has enough antibodies (or can produce quickly enough) to fight infection. Active Natural: Exposed to foreign antigen by...
ANTIBIOTICS Antibiotics are used to fight bacterial infections. There are 2 main types: Bactericidal: Antibiotic that kills bacteria Bacteriostatic: Inhibits growth of bacteria When bacteria are no longer affected by an antibiotic they are resistant. Resistance...