Replication
DNA is made in what direction?
5' to 3'
Cells split into
2 daughter cells
Segments of DNA are called
genes
Who determined the structure of DNA
Watson and Crick, used Rosalind Franklin's data
How many chromosomes does each parent give
23
What are the enzymes involved in DNA replication
Polymerase, helicase, ligase
What type of cells undergo the cell cycle stages that were focused on in this class?
Eukaryotic
Sister chromatids are
When DNA is replicated, two identical copies of DNA are formed
What is Chargoff’s Rule
Adenine (A) always pairs with thymine (T).
Guanine (G) always pairs with cytosine (C).
Therefore, in a DNA strand:
the % of adenine = the % of thymine
the % of guanine = the % of cytosine
What are the 3 phases of interphase
G1, S, G2
What is the name of the fragments making up the lagging strand?
Okazaki fragments
What is the longest phase of the cell cycle?
Interphase
Are sister chromatids connected by a centromere considered one or two chromosomes?
one
Adenine and Guanine are _
Thymine and Cytosine are _
purines.
pyrimidines.
What is G0
Cells in this state just do their job and do not prepare for cell division unless they get a signal to do so.
What does semiconservative mean?
Each strand in the DNA double helix acts as a template for the synthesis of a new, complementary strand.
M phase consists of
mitosis (prophase, metaphase, anaphase, and telophase) and cytokinesis
DNA wraps around
Histone protiens
What is a nucleosome
DNA is wrapped around proteins known as histone, This nucleosome is linked to the next one by a short strand of DNA that is free of histone
DNA has a _ structure
Anti parallel
Explain the functions of the enzymes used in DNA replication
Polymerase- adds nucleotides one by one to the growing DNA chain, incorporating only those that are complementary to the template.
Helicase- responsible for breaking hydrogen bonds between base pairs.
Ligase- join the Okazaki fragments together in the lagging strand.
cytoplasm of the cell is split in two, making two new cells
What are pairs 1-22 of chromosomes called
autosomes
When cells get ready to divide, what happens?
Chromatin condenses into chromosomes
When does DNA replication begin
DNA replication begins at the origin of replication.