MIC 102 FINAL QUESTIONS & ANSWERS
What are 3 characteristics of fungi that make them different from other materials? -
Answers -1. components in the cell wall are different
-chitin
-glycoprotein
-mixed glycans
2. ergosterol-primary sterol in fungi
3. reproduction
How is the fungal reproductive cycle different from prokaryotic reproduction? - Answers
--haploid filaments grow normally with asexual divisions.
-these filaments fuse and a dikaryon forms
-one filament cell contains 2 nuclei
-in response to changing conditions, nuclei will fuse and the true diploid will undergo
meiosis immediately to produce spores
How does yeast reproduction vary from other fungi? - Answers --most yeasts can
reproduce by asexual budding
S. cerevisiae
-haploid cells can reproduce asexually or sexually
-2 haploid mating type, a and alpha
-if close enough, they will fuse together into a single diploid cell which can sporulate but
also reproduce asexually
-meiosis of diploid produces 4 haploid spores
-haploids can switch mating types by switching which gene is expressed
Why is naming a group "protists" possibly not a good idea? - Answers --miscellaneous
group
-basically everything else that does not fit into a group
-not much unifies them other than the fact that they are microbial eukaryotes
Paramecium can reproduce in 2 different ways. What are they and what enables them
to do so? - Answers --can divide asexually through mitosis or sexually through meiosis
-most often does mitosis
-micronucleus-basic nucleus (contains one set of each gene)
-macronucleus -contains many copies of useful growth genes
-polyploid
-15% or less of the genetic content of the full genome
-sexual reproduction resets the clock
-gets rid of macronuclei and makes a new one
How does a plasmodium travel through it's hosts? Why is it important to human health?
- Answers --sporozoites travel through the bloodstream to the liver
-it infects liver cells and matures into schizonts
, -schizonts can remain dormant for some time or continue to reproduce in the liver
-schizonts rupture, releasing merozoites
-merozoites infect red blood cells
-apicoplast: organelle necessary to induce RBC's to import the merozoite.
-cycle continues
-red blood cell lysis coincides with malaria symptoms
-chills, weakness, headache, vomiting and fever
-RBC lysis may trigger cytokine release causing some of these symptoms
What ways are there to classify viruses? - Answers --viruses are mostly classified
according to phenotypic criteria because they do not have 16S rRNA to use for
phylogenetics.
-ways they classify
1. DNA or RNA
2. capsid size and shape
3. enveloped or not
What are the general stages of a viral life cycle? - Answers -1. Absorption/ attachment
2. entry-viral nucleic acid needs to enter cell
3. replication
4. release-lysis or budding
How do viruses get into cells? - Answers -non-enveloped
-T4 phage
-the tail fibers and base plate are responsible for recognition of potential host
-the tail holds the inner tube which is released upon contact
-Tip proteins degrade peptidoglycan and allow injection of DNA into host
enveloped
-proteins in lipid envelope bind to cell surface receptors
-binding induces fusion with cell membrane
-viral capsid enters into cell and releases nucleic acid once inside
-can also be taken up by endocytosis first
How do viruses get out of cells? - Answers --capsids are formed through capsomer
self-assembly.
-nucleic acids are packaged into completed/ mostly completed capsids
-once capsids are completed, non-enveloped viruses are ready for exit----> cell lysis
-enveloped viruses bud off from host cell
What mechanisms are needed to replicate different types of viral genomes? - Answers
-dsDNA
-linear molecule circularizes inside the cell
-rolling circle replication
-genome copies packed into capsid
ssDNA (+ polarity)
-(+) ssDNA acts as a template to make (-) strand
What are 3 characteristics of fungi that make them different from other materials? -
Answers -1. components in the cell wall are different
-chitin
-glycoprotein
-mixed glycans
2. ergosterol-primary sterol in fungi
3. reproduction
How is the fungal reproductive cycle different from prokaryotic reproduction? - Answers
--haploid filaments grow normally with asexual divisions.
-these filaments fuse and a dikaryon forms
-one filament cell contains 2 nuclei
-in response to changing conditions, nuclei will fuse and the true diploid will undergo
meiosis immediately to produce spores
How does yeast reproduction vary from other fungi? - Answers --most yeasts can
reproduce by asexual budding
S. cerevisiae
-haploid cells can reproduce asexually or sexually
-2 haploid mating type, a and alpha
-if close enough, they will fuse together into a single diploid cell which can sporulate but
also reproduce asexually
-meiosis of diploid produces 4 haploid spores
-haploids can switch mating types by switching which gene is expressed
Why is naming a group "protists" possibly not a good idea? - Answers --miscellaneous
group
-basically everything else that does not fit into a group
-not much unifies them other than the fact that they are microbial eukaryotes
Paramecium can reproduce in 2 different ways. What are they and what enables them
to do so? - Answers --can divide asexually through mitosis or sexually through meiosis
-most often does mitosis
-micronucleus-basic nucleus (contains one set of each gene)
-macronucleus -contains many copies of useful growth genes
-polyploid
-15% or less of the genetic content of the full genome
-sexual reproduction resets the clock
-gets rid of macronuclei and makes a new one
How does a plasmodium travel through it's hosts? Why is it important to human health?
- Answers --sporozoites travel through the bloodstream to the liver
-it infects liver cells and matures into schizonts
, -schizonts can remain dormant for some time or continue to reproduce in the liver
-schizonts rupture, releasing merozoites
-merozoites infect red blood cells
-apicoplast: organelle necessary to induce RBC's to import the merozoite.
-cycle continues
-red blood cell lysis coincides with malaria symptoms
-chills, weakness, headache, vomiting and fever
-RBC lysis may trigger cytokine release causing some of these symptoms
What ways are there to classify viruses? - Answers --viruses are mostly classified
according to phenotypic criteria because they do not have 16S rRNA to use for
phylogenetics.
-ways they classify
1. DNA or RNA
2. capsid size and shape
3. enveloped or not
What are the general stages of a viral life cycle? - Answers -1. Absorption/ attachment
2. entry-viral nucleic acid needs to enter cell
3. replication
4. release-lysis or budding
How do viruses get into cells? - Answers -non-enveloped
-T4 phage
-the tail fibers and base plate are responsible for recognition of potential host
-the tail holds the inner tube which is released upon contact
-Tip proteins degrade peptidoglycan and allow injection of DNA into host
enveloped
-proteins in lipid envelope bind to cell surface receptors
-binding induces fusion with cell membrane
-viral capsid enters into cell and releases nucleic acid once inside
-can also be taken up by endocytosis first
How do viruses get out of cells? - Answers --capsids are formed through capsomer
self-assembly.
-nucleic acids are packaged into completed/ mostly completed capsids
-once capsids are completed, non-enveloped viruses are ready for exit----> cell lysis
-enveloped viruses bud off from host cell
What mechanisms are needed to replicate different types of viral genomes? - Answers
-dsDNA
-linear molecule circularizes inside the cell
-rolling circle replication
-genome copies packed into capsid
ssDNA (+ polarity)
-(+) ssDNA acts as a template to make (-) strand
