MOD 7 Flashcards
describe bacterium
a living pathogen which is unicellular and prokaryotic - example is Tuberculosis
describe a virus
a non living pathogen that is non-cellular but contains DNA and RNA - example is Smallpox
describe fungi
a living pathogen with a cell wall and is eukaryotic - example is Thrush
define antigen
the antigen is a molecule that is recognised to be foreign, leading to an immune response.
define antibody
proteins produced by B cells in response to specific antigens as a part of the immune response.
define antibiotic
medicines that fight infections caused by bacteria in humans and animals by either killing the bacteria or slowing its growth/multiplication.
define phagocytes/phagocytosis
Phagocytes change their shape to flow around bacteria and other foreign particles. The phagocytes completely enclose the invading bacteria within their cell, where they are broken up by cellular enzymes (Phagocytosis).
define B lymphocytes
B lymphocytes, also called B cells, create a type of protein called an antibody.
define independent variable
isn’t changed by other variables and so acts as the cause of the outcome.
define dependent variable
changes as a result of the independent variable and is the effect/outcome of the experiment.
define controlled variable
stays the same throughout each experiment and is controlled by the experimenter.
define innate immune response
occurs during primary exposure to a pathogen and is the 1st and 2nd line of defence against pathogens. Examples include skin, inflammation, mucous and tears.
define adaptive immune response
occurs during secondary exposure to pathogen and is the 3rd line of defence. After the primary exposure a memory is made of the pathogen. A secondary exposure will result in a much more rapid response.
Malaria and adaptation
Malaria is a life-threatening disease caused by four species of the Plasmodium parasite. These parasites are single-celled organisms that require a human host and female Anopheles mosquitoes to complete their life cycle. At each stage different antigen molecules are produced, preventing the host from launching an effective immune response.
Direct Transmission
person-to-person: touch or exchange bodily fluids.
droplet spread: the result of droplets spray caused by talking, coughing and sneezing
Indirect Transmission
Airborne: pathogen remains in the air
contaminated objects: transmission occurs when a surface or object containing the pathogen is touched
food and water: several pathogens are transmitted as a result of improper treatment, handling, or storage of food and water
animal-to-person: usually occurs from a scratch or bite from an infected animal or from handling of waste
vector-borne: usually spread by blood sucking insects, including mosquitos, fleas, and ticks
define epidemic
epidemic diseases are those that affect a large number in one area simultaneously.
define pandemic
a pandemic to an epidemic that has spread to more than one area.
Animal Disease
Foot and mouth disease (FMD) is a highly contagious disease of cloven-hoofed animals including cattle, sheep, goats, and pigs. Australia is considered free of FMD. FMD causes fever and blisters in the mouth and hooves of cattle, sheep, goats, and pigs (and other cloven-hoofed animals).
Plant Disease
Fire blight is a devastating plant disease of pome fruit (apples, pears) worldwide. Fire blight attacks blossoms, leaves, shoots, branches, fruits, and roots. Infection results in tissue death and bacterial ooze droplets on infected tissue.
Koch’s Postulates
Koch predicted that specific microscopic pathogens cause specific disease.
- The pathogen must be found in all animals suffering from the disease, but not in healthy animals
- The pathogen must be isolated from a diseased animal and grown in pure culture.
- The cultured pathogen should cause disease when introduced into a healthy animal.
- The pathogen must be re-isolated from the experimentally infected animal.
Louis Pasteur
Prior to Pasteur, it was believed life spontaneously generated. Pasteur predicted that this was incorrect and microbes were present in the air and that food spoils when these microbes land and become active. In the Swan-Neck Flask air was let in but the bowl section with nutrient broth was being heated so any microbes were killed. All microbes were trapped in the curved section of the flask and when let in after a few days the microbes multiplied inside the nutrient broth.
Plant Responses to Pathogens
Phytophthora Cinnamomi is a fungal pathogen that affects both eucalyptus and acacia. It causes damage to all parts of the plant with symptoms including wilted, yellowing foliage, stunted growth and coloured cankers on the stems of the plant. All species of Eucalyptus produce and store oil in subdermal secretory glands. The oils have antimicrobial properties
Animal Responses to Pathogens
Some animals exhibit changes in behavior when infected. For example, they may reduce activity levels, seek isolation, or alter their feeding habits, which can help conserve energy and reduce the spread of infection. Animals often have physical barriers like skin, mucous membranes, and hair or feathers that serve as the first line of defense against pathogens by preventing their entry into the body.
Smoke Bush
Smokebush is a plant used by Aboriginal people for their healing properties in increasing the rate of healing for cuts on their skin and other skin conditions. Aboriginal peoples have used smoke bush for thousands of years for its healing properties and passed on this knowledge from generation to generation. Government agencies and pharmaceutical companies have invested significant time and millions of dollars in researching smoke bush (and other bush medicines).
Prion Protein
Transmissible and are able to induce abnormal folding of specific normal cellular proteins
Nucleoid
The Nucleoid is a region of cytoplasm where the chromosomal DNA is located.
Cytoplasm
Cytoplasm is the gelatinous liquid that fills the inside of a cell.
Cell Wall
Is responsible for the characteristic shape of the cell.
