Introduction to microorganisms

Question 1

List the six stages of the chain of infection.

Answer 1

Infectious agent, Reservoir, Portal of exit, Mode of transmission, Portal of entry, Susceptible host

Question 2

What are 3 standard precautions or safety measures undertaken in a clinical setting.

Answer 2

Hand hygiene, PPE (Personal protective equipment), disposal of sharps, waste management, routine cleaning.

Question 3

The study of organisms too small to be seen with the naked eye

Answer 3

Microorganisms

Question 4

Example of Prokaryote

Answer 4

Bacteria

Question 5

Example of Eukaryote

Answer 5

Fungi, Protozoa, yeast and mould

Question 6

Example of a non cellular microorganism

Answer 6

Virus

Question 7

State 3 difference between prokaryote and eukaryote microorganisms,.

Answer 7

Pro - Unicellular Eu - Multicellular
Pro - NO Eu - membrane-bound organelles
Pro - DNA not in a membrane Eu - DNA in membrane

Question 8

The first word in the name is the _____ with the first letter always written in capitals

Answer 8

Genus

Question 9

The second is the _____ which is not written as a capital.

Answer 9

species

Question 10

When writing the both words of a scientific name of a microorganism what do you do?

Answer 10

Underline it

Question 11

Escherichia can also be written as

Answer 11

E. Coli

Question 12

What is beneficial bacteria?

Answer 12

Assist with various body processes and/or Crowd out and prevent infection by harmful bacteria

Question 13

What is opportunistic bacteria?

Answer 13

Microflora that is potentially harmful and can cause disease under certain conditions

Question 14

What is Resident microflora ?

Answer 14

Species that are always in or on the human body found on skin and conjunctiva

Question 15

Describe structure and function of the capsule of bacteria.

Answer 15

outer surface of a bacteria cell, aids in attachment to surfaces.

Question 16

Describe structure and function of the cell wall of bacteria.

Answer 16

maintains the shape of the cell, offers protection from environmental factors

Question 17

Describe structure and function of the cell membrane of bacteria.

Answer 17

phospholipid bilayer which is selectively permeable, allowing some particles to pass through.

Question 18

Describe structure and function of the cytoplasm of bacteria.

Answer 18

substance inside of a cell membrane, 80% water acting as a medium for many metabolic reactions in the cell.

Question 19

Describe structure and function of the ribosomes of bacteria.

Answer 19

found in random grouping , functions as the site of protein synthesis.

Question 20

Describe structure and function of the chromosome/nucleiod of bacteria

Answer 20

consists of a single, long molecule of DNA and contains the genetic information for metabolism and reproduction.

Question 21

Describe structure and function of the plasmid of bacteria

Answer 21

small, circular, double stranded piece of DNA, doesn’t carry genes for normal function. carries genes for antibiotic resistance.

Question 22

Describe structure and function of the pill/fimbriae of bacteria

Answer 22

this, hair like structure on surface of many negative cells. helps cell attach to surfaces and can transfer genetic information.

Question 23

Describe structure and function of the flagellum of bacteria

Answer 23

some bacteria have these, they propel the cell along. long thread like attachment.

Question 24

Describe structure and function of the endospore of bacteria

Answer 24

formed by certain bacteria in unfavourable conditions and are resistant to heating and drying.

Question 25

What are the main characteristics of Fungi?

Answer 25

found everywhere, can only live on organic material in water and soils, some are parasitic/harmful/beneficial, fungi grow where bacteria dont thrive,

Question 26

What are the main characteristics of mould?

Answer 26

they grow on substances with low moisture, able to grow in high sugar and salt concentrations, many prefer acidic conditions (fruit) and they can tolerate cold conditions.

Question 27

What are the main characteristics of yeasts?

Answer 27

yeasts are found in soil and water and the surface of fruit and vegetables. yeasts can be used for fermentation to produce wine and beer.

Question 28

Describe and state an example of superficial fungal infection.

Answer 28

Superficial infections occur on the outer parts of the body e.g. skin, hair, nails Examples: Tinea pedis (athlete's foot), Tinea corporis (ringworm)

Question 29

Describe and state an example of systemic fungal infection.

Answer 29

Affect tissues and organs deep within the body e.g. lungs Example: Aspergillosis

Question 30

Describe and state an example of opportunist fungal infection.

Answer 30

Fungal infections caused by fungi that are normally harmless. Example: Vaginal or oral thrush

Question 31

Name the main characteristic of protozoa and how they move

Answer 31

Eukaryote cells, Most are unicellular free-living microorganisms, They are usually found in soil or water, protozoa ingest food and digest within the cell. They move by locomotion.

Question 32

Give an example of protozoa in the body

Answer 32

Plasmodium spp. causes Malaria, Giardia intestinalis causes Giardiasis, Toxoplasma gondii which causes Toxoplasmosis

Question 33

Describe the structure of viruses

Answer 33

* Single type of nucleic acid - either RNA or DNA * Protein coat or ‘capsid’ surrounds the nucleic acid * In some viruses, a membrane-like envelope surrounds the capsid * Protein spikes on envelope aid in attachment and entry to host cells

Question 34

list characteristics of viruses that distinguish from cellular organisms.

Answer 34

* Viruses do not have a cell structure i.e. they are acellular * Viruses require a host cell in order to replicate * Most viruses can only infect specific cells of one particular species

Question 35

What are the Steps in Virus Replication

Answer 35

1. Attachment to appropriate host cell 2. Entry and uncoating (capsid removal by host enzymes) 3. Replication of viral nucleic acid and synthesis of viral proteins 4. Assembly of new complete virus particles Release of virus particles from host cell (which may burst

Question 36

Give 3 examples of viral infections.

Answer 36

influenza, mumps, rubella ,measles, rubella

Question 37

Giva an example of Latent Viral Infections.

Answer 37

Herpes