Pathophysiology - Chapter 6 - Practice Questions With Expert-verified Answers

Pathophysiology - Chapter 6 - Practice Questions Microbiology - ANS Study of microorganisms or microbes, very small living forms that are visible only with a microscope Microorganisms - ANS Bacteria, fungi, protozoa, and viruses Bacteria - ANS Classified as prokaryotic cells because they are very simple in structure lacking even a nuclear membrane but function metabolically and reproduce. Have a complex cell wall structure Eukaryotic cells - ANS Nucleated cells found in higher plants and animals including humans lack cell walls except in Plants but their DNA is enclosed in a nuclear membrane and the cell membrane has a complex structure Non-pathogenic microorganisms - ANS Do not usually cause disease in fact they are often beneficial Pathogens - ANS Disease-causing microbes often referred to as germs Infectious diseases result from Invasion of the Body by microbes and multiplication of these microbes followed by damage to the body Germ theory of disease - ANS Contact from the eighteenth and nineteenth centuries when scientists experimented on fermentation and spoilage of foods. Transmission of pathogens and infections through hands, surfaces, water, and the air was documented and the practices of asepsis were begun Types of microorganisms - ANS Bacteria Viruses Chlamydiae Rickettsiae Mycoplasmas Fungi Protozoa Bacteria discription - ANS Unicellular (single cell) organisms that do not require living tissue to survive. Berry and size, shape, and arrangement and are classified and named accordingly Major groups of bacteria based on cellular shape - ANS Bacilli Spirals Cocci Bacilli - ANS A bacteria - rod-shaped organisms which include vibrio (curved rods) and pleomorphic (variable or indistinct shape) Spirals - ANS A bacteria which includes spirochetes and spirilla with a coiled shape or wavy line appearance. A spirochete contains a structure called an axial filament or as the spirilla have flagella. Both of these structures facilitate cell movement Cocci - ANS Spherical forms Bacterial cells categorized by their characteristic groupings or Arrangements - ANS Diplo Strep (to) Staph (ylo) Tetrads Palisade Diplo - ANS Prefix indicating pairs Strep (to) - ANS Prefix indicating chains Staph(ylo) - ANS Prefix indicating irregular, grape-like clusters Tetrads - ANS Cells grouped in a packet or Square of for cells Palisade - ANS Sells line together with the long sides parallel Basic structure of bacteria - ANS 1. Outer rigid cell wall, gram-positive or Gram-negative. Penicillin is effective against gram-positive bacteria. Targeting cell wall structure and function is important because human cells do not have cell walls 2. Cell membrane located inside the bacterial cell wall. This semipermeable membrane selectively controls movement of nutrients and other materials in and out of the cell. Metabolic processes also take place in the cell membrane 3. An external capsule or slime layer is found on some but not all bacteria. Found outside the cell wall and offers additional protection to the organism. It interferes with the phagocytosis by macrophages and white blood cells in the human body 4. One or more rotating Flagellae attached to the cell wall provide Mobility for some species 5. Pili or fimbriae tiny hair-like structures found on some bacteria usually in the gram-negative class assist in attachment of the bacterium to tissue and also and transfer of genetic material or DNA to another bacterium thus leading to Greater genetic variation 6. Cytoplasm contained in the bacteria which contains the chromosome composed of one long strand of DNA, ribosomes and RNA, and plasmids, which are DNA fragments that are important in the exchange of genetic information with other bacteria. Plasmids commonly contain genetic information conveying drug resistance shared with many other types of bacteria. This cellular component provides for the metabolism, growth, reproduction, and unique characteristics of the bacterium