What are some key differences in replication between E. coli DNA and ? phage DNA?
What will be an ideal response?
Both start replication as a circular molecule, and in E. coli, the parental DNA strands remain in a circular form throughout the replication cycle. A replication bubble opens to form two replication forks, and replication proceeds bidirectionally. Lambda phage DNA is replicated by a rolling circle mechanism, in which a nick is made in one of the two strands of the circle, and the 5' end of the cut DNA strand is rolled out as a free "tongue"of increasing length as replication proceeds. The parental DNA circle is replicated continuously, while the linear displaced strand is replicated discontinuously. As long as the circle continues to roll, concatamers of phage DNA can be produced. This is later cut up into linear chromosomes and packaged into new phage heads.
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One way in which deforestation contributes to global climate change is that the conversion of forest to cropland or
pasture ____. a. decreases the amount of methane released by microbes b. increases the amount of nitrogen oxides in the air c. decreases the amount of sulfur dioxides in the air d. increases the rate at which carbon is taken up by plants e. decreases the rate at which carbon is taken up by plants
If phospholipids form a spherical structure when placed in water, then which of the following is the most logical
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Since sodium-potassium pumps transport sodium ions out of a cell and potassium ions into a cell, what type of carrier
proteins are they? a. ion pumps b. uniporters c. symporters d. antiporters e. ABC transporter
The ability of oxygen to combine with and detach from hemoglobin is influenced by which of the following factors?
a. percent oxygen saturation b. humidity c. oxygen concentration d. tidal volume e. partial pressure