Unit 8: DNA and cell division Flashcards
nucleotide
the subunit of DNA a sugar, phosphate, and a base
Where the DNA is in the cell
nucleus
chromosome
one DNA molecule tightly packaged
double helix
the shape of the two DNA strands when they wind around each other
gene
a piece of a DNA molecule / chromosome
hundreds or thousands of nucleotides
the information to build one protein
genome
the entire set of DNA inside the nucleus (for humans, 46 chromosomes)
karyotype
a medical test which looks at all your chromosomes to see if they look healthy
DNA replication
takes place in the nucleus
builds new strands of DNA against the old strands
helicase
an enzyme which unwinds the DNA double helix
DNA polymerase
an enzyme which builds the new DNA strand against the old DNA strand
Cell cycle
The stages a cell goes through before dividing: G1, S, G2, M
interphase
the time in which the cell functions, grows, and builds new parts before dividing
prophase
the DNA condenses into chromosomes (X shaped)
the nucleus dissolves
the spindle starts to form
metaphase
The chromosomes line up at the cell’s equator
the spindle is fully formed
anaphase
The spindle contracts, pulling apart the chromosomes. The sister chromatids move towards opposite ends of the cell.
many chromosomes
the genome
the cell cycle
one chromosome
containing replicated DNA (2 sister chromatids)
Karyotype
