Transcript Slide 1

Intro to DNA Replication
A QUICK REFRESHER
• Where is DNA found?
• nucleus
• Where else?
• mitochondria, chloroplast (the
endosymbiont theory)
• What form does DNA take in the
nucleus?
• chromosome
• How do the 150 million base pairs
that make up the human genome fit
into the nucleus?
• wrapped around histones
• coiled and supercoiled
chromatin condenses into
chromosomes
•
What is a karyotype?
• A picture of all the
chromosomes found in a cell
• How many
chromsomes are found
in a human somatic
cell?
• 23 pairs (46 total)
• How many
chromosomes are found
in human gametes?
• 23
• Is this person male or
female?
• male
• All cells can give rise to a new
generation of cells via the cell cycle
•S phase of interphase
•DNA replicates
• Mitosis
• Replicated DNA splits between
two nuclei
• Cytokinesis
• Cytoplasm splits between two
daughter cells
• Each daughter cell has an exact
copy of the parent cell’s DNA
Meselson and Stahl
DNA Replication - The Process