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In bacteria, DNA binding proteins and alternative sigma factors play an important role in ______.

When sequencing DNA using the Sanger (dideoxy) sequencing method, we rely on all of the following EXCEPT ______.

You conduct an Ames test on a chemical you suspect might be a carcinogen. Following incubation, you find some colonies on your control plate. Why do you see some colonies on your control plate?

Pathogenic Streptococcus pneumoniae possess a polysaccharide capsule that prevents phagocytosis, allowing them to evade the immune system and multiple, causing pneumonia. S. pneumoniae that lack the capsule do not cause disease as they are readily destroyed by host phagocytes. When a mixture of living nonencapsulated and heat-killed encapsulated S. pneumoniae are injected into a mouse, the mouse dies, and living capsulated bacteria can subsequently be isolated from the mouse. Which of the following best explains this result?

Following from the previous two questions about Anabaena, would you find mRNA that is different between these two cell types, photosynthetic and nitrogen fixing heterocyst? If so, what would it represent?

If you could extract and quantify all the mRNA in a single cell, this would essentially be a measure of:

When sequencing DNA using the Sanger (dideoxy) sequencing method, we rely on all of the following EXCEPT ______.

Following from the previous two questions about Anabaena, would you find mRNA that is different between these two cell types, photosynthetic and nitrogen fixing heterocyst? If so, what would it represent?

In bacteria, DNA binding proteins and alternative sigma factors play an important role in ______.

Consider the cyanobacteria Anabaena. Individual cells grow attached to each other in long chains produced from binary fission with cells remaining attached (e.g., streptococcus). Most perform photosynthesis, using photosystems I and II to generate ATP and NADPH that they use to power the fixation of carbon dioxide via the Calvin cycle. However, a small number form heterocysts, cells that instead of performing photosynthesis, fix nitrogen into ammonium. Heterocysts share their nitrogen compounds with their photosynthetic neighbors, who in turn share sugars with the heterocysts. If you extracted all the mRNA from a single heterocyst, and all the mRNA from a single photosynthetic cell, what information would this give you, i.e., what would this tell you about them?