4- Infection Agents Flashcards
What’s the difference between prokaryotes and eukaryotes
Prokaryotes do not have internal membranes
(few exceptions of photosynthetic bacteria)
Eukaryotes have internal membranes that define organelles including nucleus, ER, mitochondria, etc
2) Prokaryotes have a single copy of a chromosome (haploid) vs. eukaryotes (ie haploid or diploid). Usually prokaryotes have a single chromosome
3) Eukaryotes have cytoskeleton
Prokaryotes cytoskeleton is not as well defined.
4) Cell wall of prokaryotes contain peptido-glycan
What are viruses
not cells in their own right - OBLIGATE PARASITES
•Contain RNA or DNA genetic material
•Make use of a host cell nuclear synthetic machinery to replicate
•Show host specificity but infect almost all other life forms, including bacteria
•Divide by budding out of host cell
•Various routes of infection
How can Protozoa cause disease
Unicellular eukaryotic organisms
–include intestinal, blood and tissue parasites
–replicate in the host by binary fission or by formation of trophozoites inside a cell
–many have a complicated life cycle involving two hosts
–infection is acquired by ingestion or through a vector
eg insect or invertebrate vector
•Malaria and Leishmaniasis
How can helmith parasites cause disease
Roundworms
•Flatworms (flukes)
•Tapeworms
- Metazoa with eukaryotic cell structure
- Multi-cellular
- Visible to the naked eye
- Have life cycles outside the human host
- Life cycle complexity varies from simple embryonation to alternation of generations in different hosts
