MOD 7

Question 1

describe bacterium

Answer 1

a living pathogen which is unicellular and prokaryotic - example is Tuberculosis

Question 2

describe a virus

Answer 2

a non living pathogen that is non-cellular but contains DNA and RNA - example is Smallpox

Question 3

describe fungi

Answer 3

a living pathogen with a cell wall and is eukaryotic - example is Thrush

Question 4

define antigen

Answer 4

the antigen is a molecule that is recognised to be foreign, leading to an immune response.

Question 5

define antibody

Answer 5

proteins produced by B cells in response to specific antigens as a part of the immune response.

Question 6

define antibiotic

Answer 6

medicines that fight infections caused by bacteria in humans and animals by either killing the bacteria or slowing its growth/multiplication.

Question 7

define phagocytes/phagocytosis

Answer 7

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).

Question 8

define B lymphocytes

Answer 8

B lymphocytes, also called B cells, create a type of protein called an antibody.

Question 9

define independent variable

Answer 9

isn’t changed by other variables and so acts as the cause of the outcome.

Question 10

define dependent variable

Answer 10

changes as a result of the independent variable and is the effect/outcome of the experiment.

Question 11

define controlled variable

Answer 11

stays the same throughout each experiment and is controlled by the experimenter.

Question 12

define innate immune response

Answer 12

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.

Question 13

define adaptive immune response

Answer 13

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.

Question 14

Malaria and adaptation

Answer 14

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.

Question 15

Direct Transmission

Answer 15

person-to-person: touch or exchange bodily fluids.

droplet spread: the result of droplets spray caused by talking, coughing and sneezing

Question 16

Indirect Transmission

Answer 16

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

Question 17

define epidemic

Answer 17

epidemic diseases are those that affect a large number in one area simultaneously.

Question 18

define pandemic

Answer 18

a pandemic to an epidemic that has spread to more than one area.

Question 19

Animal Disease

Answer 19

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).

Question 20

Plant Disease

Answer 20

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.

Question 21

Koch’s Postulates

Answer 21

Koch predicted that specific microscopic pathogens cause specific disease.

1. The pathogen must be found in all animals suffering from the disease, but not in healthy animals
2. The pathogen must be isolated from a diseased animal and grown in pure culture.
3. The cultured pathogen should cause disease when introduced into a healthy animal.
4. The pathogen must be re-isolated from the experimentally infected animal.

Question 22

Louis Pasteur

Answer 22

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.

Question 23

Plant Responses to Pathogens

Answer 23

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

Question 24

Animal Responses to Pathogens

Answer 24

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.

Question 25

Smoke Bush

Answer 25

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).

Question 26

Prion Protein

Answer 26

Transmissible and are able to induce abnormal folding of specific normal cellular proteins

Question 27

Nucleoid

Answer 27

The Nucleoid is a region of cytoplasm where the chromosomal DNA is located.

Question 28

Cytoplasm

Answer 28

Cytoplasm is the gelatinous liquid that fills the inside of a cell.

Question 29

Cell Wall

Answer 29

Is responsible for the characteristic shape of the cell.