gene structure dna replication. figure 7.4a figure 7.5
TRANSCRIPT
Gene structureDNA replication
Figure 7.4A
Figure 7.5
• The DNA double helix has grooves: a wide major groove and a narrow minor groove.
•
• - These provide DNA-binding proteins access to base sequences.
DNA Structure
Figure 7.6
• RNA differs from DNA:
• - Usually single-stranded
• - Contains ribose sugar
• - Uracil replaces thymine
RNA Structure
Figure 7.4B
• Bacteria pack their DNA into a series of loops or domains, collectively called the nucleoid.
• - Loops are anchored by histone-like proteins
The Bacterial Nucleoid
Figure 7.8
DNA Replication • Replication of cellular DNA in most cases is
semiconservative.• - Each daughter cell receives one parental
and one newly synthesized strand.Figure 7.13
Figure 7.14
Figure 7.15
Figure 7.18a
Figure 7.18b
• Animation: DNA Replication
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DNA Replication
Figure 7.19
Figure 7.21
• Restriction endonucleases cleave DNA at specific recognition sites, which are usually 4 to 6 bp and palindromes.
•
• - May generate blunt or staggered ends
Figure 7.27A
Analysis of DNA
• Agarose gel electrophoresis can be used to analyze the DNA fragments obtained by treatment with restriction enzymes.
Figure 7.27B
Analysis of DNA
• The polymerase chain reaction (PCR) can produce over a million-fold amplification of target DNA within a few hours.
Figure 7.29
Analysis of DNA