Chapter 13 Pt. 3 (Final Exam Pt. 8) Flashcards
Is a virus a living organism? Why or why not?
a virus is not a living organisms, because it cannot perform any life processes on it’s own
True or False: viruses are smaller than bacteria
True
viruses consist of a strand or strands of genetic material, either ____ or ____, surrounded by _______
DNA
RNA
capsid
What is a capsid?
a coat of protein
What makes up the structure of a typical virus?
glycoprotein
envelope
capsid
viral DNA
Which structure of a typical virus is this:
stud the outside of the envelope
glycoprotein
Which structure of a typical virus is this:
an outer membranous layer studded with glycoproteins; surrounds the capsid and viral DNA
envelope
Which structure of a typical virus is this:
a coat of protein surrounds the viral DNA
capsid
steps in viral replication: (1) (2) penetration (3) production of viral genetic information and proteins (4) assembly of new viruses (5) release What is step 1, and what happens?
(1) attachment
- the virus attaches to a specific receptor on the host cell
- this is responsible for host specificity
steps in viral replication: (1) attachment (2) (3) production of viral genetic information and proteins (4) assembly of new viruses (5) release What is step 2, and what happens?
(2) penetration
- all or part of the virus enters the host cell
- in the case of animal cells, the entire virus enters the cell
steps in viral replication: (1) attachment (2) penetration (3) (4) assembly of new viruses (5) release What is step 3, and what happens?
(3) production of viral genetic information and proteins
- the virus directs structures in the host cell to make parts of new viruses
steps in viral replication: (1) attachment (2) penetration (3) production of viral genetic information and proteins (4) (5) release What is step 4, and what happens?
(4) assembly of new viruses
- newly synthesized viral genetic information and proteins are used to form new viruses
steps in viral replication: (1) attachment (2) penetration (3) production of viral genetic information and proteins (4) assembly of new viruses (5) What is step 5, and what happens?
(5) release
- new viruses leave the cell
- some viruses leave by a process called budding (or shedding)
What are the different types infections?
(1) Lytic Infection
(2) Persistent Infection
(3) Latent Infection/Primary Infection
Which type of infection is this:
Rapid releases of new viruses from infected cell causes cell death.
Symptoms of the disease depend on which cells are killed.
Lytic Infection
Which type of infection is this:
Slow release of new viruses allows the cell to remain alive and continue to produce new viruses for a prolonged period.
Persistent Infection
Which type of infection is this:
Delay between infection and symptoms.
Virus is present in the cell without harming the cell.
Symptoms begin when the virus starts to actively replicate, and new viruses exiting the host cell can cause cell death.
Latent Infection/ Primary Infection
What is the best way to fight viral infections?
vaccines
What are protozoans?
single-celled eukaryotic organisms with a well-defined nucleus
What are fungi?
are eukaryotic organisms with a well-defined nucleus in their cells
True or False: Most fungal infections cannot be cured
False; most fungal infections can be cured
What are parasitic worms?
multicellular animals that benefit from a close, prolonged relationship with their hosts while harming, bur usually not killing
What is ascariasis?
caused by a large roundworm, ascaris, that is about the size of an earthworm
What are prions?
infectious particles of proteins
What are different ways that diseases spread?
- Direct Contact
- Indirect Contact
- Contaminated food or water
- Animal Vectors
- Intravenous Drug Use
What is an epidemic?
a large-scale outbreak of an infectious disease
What are some of the most notorious epidemics?
bubonic plague
cholera
diphtheria
smallpox
What is the difference between emerging and reemerging disease?
emerging disease- one with clinically distinct symptoms whose incidence has increased, particularly over the past two decades
reemerging disease- one that has reappeared after a decline in incidence
What are the 4 factors that play important roles in the emergence and reemergence of disease?
(1) development of new organisms that can infect humans and development of drug-resistant organisms
(2) environmental change
(3) population growth
(4) failure to vaccinate
What are the important factors determining where new infectious diseases will emerge?
(1) the rate of human population growth and the density of the human population
(2) the number of species of wild mammals
What is epidemiology?
the study of patterns of disease
What is the difference between sporadic diseases, endemic diseases, and epidemic disease?
(1) sporadic diseases-occur only occasionally unpredictable intervals
(2) endemic diseases- are always present in a population and pose little threat
(3) epidemic disease- occurs suddenly and spreads rapidly to many people
What is a pandemic?
a global outbreak of disease
Which type of disease is this:
affect a few people within a restricted area
sporadic diseases
Which type of disease is this:
common cold
endemic diseases
Which type of disease is this:
smallpox and cholera
epidemic disease
Which type of disease is this:
HIV/AIDS
pandemic
