Lecture 1 Flashcards
The basic structure of a virus
consist of nucleic acids and, in some cases, a protein shell known as a capsid
What do viruses do in the body
Viruses enter cells and divert the synthetic processes of those cells towards their own replication. In some cases this high jacking
can kill (or not) the host cell. Other bacteria are more complex than viruses but still only multiply in living cells. Within the cells they have a recognizable morphology and life cycle.
Basic structure of a bacteria
Prokaryotes, have a rigid cell wall with cytoplasm and their genetic material organized into a circular chromosome (plasmid)
Basic structure of a mycoplasma
similar to bacteria but do not have the rigid cell wall, and are
consequently more delicate.
Basic structure of a eukaryote
comprises all unicellular and multicellular animals and plants. The genetic material is organised into a nucleus.
What is resident bacteria
occupy a particular body site and form part of the normal flora. They constantly live in our bodies (ex// residents of a city)
What is transient bacteria
Transient flora is found in a specific location often as a result of displacement of resident flora, injury or trauma, or through human behaviour. (ex// tourists of a city)
What is immunology
study of our protection from foreign macromolecules or invading organisms and our responses to them
What are the 4 different classes of organisms
Viruses, Mycoplasma, Bacteria, Parasites
Where should there be no bacteria?
Brain, eyes, heart, CNS, circulatory system, inside organs
What are the three things our normal flora can do for us?
- Protection from invasive bacteria by taking up space
- Metabolism
- Immune stimulation
What are our mechanical barriers?
Physically involved to keep bacteria out. The number one is skin, then saliva, mucous, tears, hair, etc.
What are 4 ways bacteria can get into the body
- Adherence
- Toxin production (destroys some of our defenses)
- Opportunism
- Compromised host
What are 2 ways bacteria can use opportunism to get in
- Immune system has been compromised
- If bacteria goes where its not supposed to go
In these conditions, even good bacteria can have damaging effects
What is bacteremia
The presence of bacteria in the blood
What is septicameia
Poisoning caused by bacteria in the blood
How does microbial disease occur?
In order to enter, they need to colonize (actively establish and multiply in/on body). Then, when damage occurs to the host, clinic infection occurs.
What is clinical infection?
Disease that is easy to see due to abnormal presentation (ex// seeing clear symptoms in a patient)
What is contamination
deposition without multiplication
bacteria don’t have to actively work to infect you, the bacteria is directly inserted into your body (ex// dirty needle)
What component is common to both bacterial and archaeal cell walls?
A. Chitin
B. Cellulose
C. Peptidoglycan
D. Silica
c
Which of the following is NOT a characteristic of viruses?
A. Have DNA or RNA, but never both
B. Require living cells to reproduce
C. Can be treated effectively with antibiotics
D. Have a protein coat that encloses their genetic material
c
The presence of which organelle differentiates a eukaryotic from a prokaryotic cell?
A. Ribosomes
B. Cell membrane
C. Nucleus
D. Cell wall
c
What is the primary role of the bacterial cell wall?
A. To facilitate movement
B. To protect genetic material
C. To prevent the cell from bursting in hypotonic environments
D. To capture energy from sunlight
c
How do prions cause disease?
A. By bacterial infection
B. By viral infection
C. By causing misfolding of other proteins
D. By genetic mutations
c
