Medical Science

Question 1

What is a pathogen?

Answer 1

A disease-causing organism.

Question 2

What is an antigen?

Answer 2

Any foreign particle that stimulates an immune response.

Question 3

Describe chloroplasts.

Answer 3

Contain the green pigment chlorophyll. Site of photosynthesis. Located in plant cells only.

Question 4

Describe a cell wall.

Answer 4

Made of cellulose. Protects the cell and gives it its rigid structure. Located in plant cells.

Question 5

Describe the cytoplasm.

Answer 5

Jelly-like substance that fills the cell and contains many different organelles that perform specific tasks. Located in both types of cells.

Question 6

Describe the cell membrane.

Answer 6

Holds the cytoplasm together and controls the movement of substances in and out of the cell. Located in both types of cells.

Question 7

Describe the cell nucleus.

Answer 7

Controls cell growth, division and repair. Contains chromosomes (made of DNA) which carry our genes. Located in both types of cells.

Question 8

Describe vacuoles.

Answer 8

Storage compartments (for water, glucose, starch, gases) within the cell. Located in plant cells, not usually in animal cells.

Question 9

Describe mitochondria.

Answer 9

Miniature powerhouses within the cell. Site of cellular respiration.

Question 10

What is the word equation for photosynthesis?

Answer 10

Carbon dioxide + water ————-(sunlight over chlorophyll) gives glucose + oxygen

Question 11

What is the word equation for cellular respiration?

Answer 11

Glucose + oxygen ————-(mitochondria) gives carbon dioxide + water + energy

Question 12

What are the needs of cells?

Answer 12

To get nutrients (glucose, amino acids, minerals…) in, wastes (urea, carbon dioxide) out, water in and out, and oxygen in.

Question 13

Why do multicellular organisms require specialised cells?

Answer 13

Multicellular organisms require specialised cells to carry out all the different functions required to keep us alive.

Question 14

What is a disease?

Answer 14

A disease is an abnormal condition affecting the ability of any of the body’s systems to function normally.

Question 15

How are specialised cells arranged?

Answer 15

• Tissues (collections of similar cells)
• Organs
• Organ systems
• Multicellular organisms

Question 16

What are the major organ systems that provide our cells with their needs?

Answer 16

Circulatory, respiratory, excretory and digestive systems.

Question 17

What are the two things disease can be caused by?

Answer 17

External factors (such as infectious diseases) or internal dysfunction (such as auto-immune diseases).

Question 18

What are the two main categories of disease?

Answer 18

Infectious diseases and non-infectious diseases.

Question 19

What are the three types of non-infectious diseases?

Answer 19

Deficiency, hereditary and physiological diseases.

Question 20

What is an infectious disease?

Answer 20

A disease resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism.

Question 21

What are communicable diseases?

Answer 21

Diseases you can catch (same as infectious diseases).

Question 22

What are some ways transmission of pathogens can occur?

Answer 22

Physical contact, contaminated food, exchange of bodily fluid, contact with objects, air-borne inhalation or by vector organisms.

Question 23

What is a vector?

Answer 23

Any agent (person, animal, microorganism) that carries and transmits an infectious pathogen into another living organism.

Question 24

What are infectious diseases also known as?

Answer 24

Transmissible diseases, which comprise those diseases that are contagious and non-contagious.

Question 25

What are contagious diseases?

Answer 25

Diseases that are easily transmitted by physical contact with the person suffering the disease, or by their secretions or objects touched by them.

Question 26

What are non-contagious diseases?

Answer 26

Infectious diseases that require a special mode of transmission between hosts - an intermediate or vector species, direct blood contact, or sexual contact.

Question 27

What are the different types of pathogens?

Answer 27

Bacteria, viruses, protozoans, prions, fungi and macroparasites.

Question 28

Describe bacteria.

Answer 28

Single-celled organisms whose DNA is not contained inside a membrane bound nucleus. It's typical size is 0.2-5 micrometers. Examples of diseases caused by bacteria are tetanus, cholera, tuberculosis, salmonella, typhoid, golden staph, syphilis, scarlet fever.

Question 29

Describe a virus.

Answer 29

Consists of a piece of DNA or RNA wrapped in a protein coat. Viruses cannot reproduce unless inside a host cell. It's typical size is 20-300 nanometers. Examples of diseases caused by viruses are AIDS, influenza, hepatitis, SARS, measles, herpes, rubella.

Question 30

Describe protozoans.

Answer 30

Single-celled organisms whose DNA is inside a membrane bound nucleus. Has no cell wall. Its typical size is 2-200 micrometers. Examples of diseases caused by protozoans are malaria, toxoplasmosis, amoebic dysentery, cryptosporidium, giardia.

Question 31

Describe fungi.

Answer 31

Made up of one or more cells that have a cell wall, true nucleus and no chloroplasts. Its typical size varies, from 50 micrometers to much larger. Examples of diseases caused by fungi are thrush, ringworm, athlete's foot, onychomysis.

Question 32

Describe prions.

Answer 32

Incorrectly shaped proteins. Its typical size is 10-200 nanometers. Examples of diseases caused by prions are BSE, kuru, and fatal familial insomnia.

Question 33

Describe macroparasites.

Answer 33

Multicellular organisms. Can be seen without a microscope. Include head lice, fleas, flatworms and elephantiasis.

Question 34

In ideal conditions, how quickly can a single bacterium multiply?

Answer 34

In under thirty minutes.

Question 35

What are the reasons we feel sick?

Answer 35

- cells of our tissues and organs are killed by pathogens, therefore organs cannot function fully - pathogens are in competition with our cells for nutrients - waste products may be poisonous (toxins) or they may interfere with our body's control systems (eg temperature, resulting in fever) - immune responses (eg inflammation)

Question 36

How are bacteria classified?

Answer 36

According to shape.

Question 37

What is a round bacteria called?

Answer 37

Cocci (plural coccus)

Question 38

What is a rod-shaped bacterium called?

Answer 38

Bacilli (plural bacillus)

Question 39

What are spiral shaped bacteria called?

Answer 39

Spirilla

Question 40

What are bacteria in clumps called?

Answer 40

Staphylo _________

Question 41

What are bacteria in a line called?

Answer 41

Strepto ________

Question 42

How many lines of defence are there and what do they do?

Answer 42

The human body sets up three lines of defence which are natural barriers against pathogens which cause infectious diseases.

Question 43

What is an antiseptic?

Answer 43

Capable of preventing infection by inhibiting the growth of microorganisms.

Question 44

What is a disinfectant?

Answer 44

An agent, such as heat, radiation or chemical, that inhibits the growth of disease causing microorganisms.

Question 45

Define quarantine.

Answer 45

The enforced isolation or restriction of free movement to prevent the spread of contagious diseases.

Question 46

Define sterilisation.

Answer 46

The process of removing or killing organisms from a surface or object.

Question 47

Define antibiotic.

Answer 47

A substance, such as penicillin, produced by or derived from certain fungi, bacteria or other organisms that destroy or inhibit the growth of disease causing microorganisms.