9/17/24, 11:24 BIO 210 Exam Review - Includes items from
AM each unit
Cell Cycle:
● Interphase:
○ G0: No growth signal is produced
○ G1: Growth signal is produced, and the cell prepares for division
○ S-phase: DNA replicates
○ G2: two centrioles, chromosomes are replicated w/sister chromatids
● Mitosis…
Mitosis:
● Prophase: Chromosomes condense, centrioles divide and begin moving to opposite poles,
nuclear envelope begins to dissolve
● Metaphase: Spindle fibers attach to kinetochore and line up in the middle of the cell
● Anaphase: Sister chromatids separate to opposite poles (disjunction)
● Telophase: Cell splits, nuclear envelopes re-form and chromosomes de-condense
Meiosis:
● Purpose: produces gametes
○ 4n rather than 2n (more genetic material!!)
○ Spermatogenesis = 4 cells w/n chromosomes
○ Oogenesis = 1 egg cell with 2 small polar bodies
● Prophase 1: recombination/crossing over
● Metaphase 1: random alignment
● Anaphase 1: full homologous chromosomes, not sister chromatids
● Telophase 1: cytokinesis with optional interphase
● Prophase 2: Same as mitosis
● Metaphase 2: Same as mitosis
● Anaphase 2: Same as mitosis
● Telophase 2: Results in 4 cells with n chromosomes (haploid)
DNA Structure:
● Practice on paper (+RNA structure)
● Right-handed helix
● Phosphate backbone
○ Hydrophilic
● Phosphodiester bonds
○ Joins two nucleotides
● Major groove: big “gap”
● Minor groove: small “gap”
about:blan 1/
k 9
, 9/17/24, 11:24 BIO 210 Exam Review - Includes items from
AM each unit
DNA Experiments:
● Meselson-Stahl:
○ Models of DNA replication
■ Conservative: replication = original DNA & copy
● 1 band would contain DNA solely composed of old DNA, and the
other would contain DNA exclusively composed of new DNA
■ Dispersive: replication = 2 DNA with patches of old & new throughout
● Prediction: would show intermediate bands where the DNA would
be mixed together in each DNA molecule.
■ Semi-conservative: 2 DNA with one old strand and one new strand
● hybrid band in the first replication, each DNA molecule consisted
of 1 strand of the original DNA and 1 newly synthesized DNA.
● Griffith: establish transforming principle
○ Smooth → mouse dies
○ heat-killed smooth → mouse lives
○ rough → mouse lives
○ heat-killed + rough → mouse dies
● Avery, Mcleod, McCarthy: determine transforming principle
○ Treat heat-killed S with RNase (no RNA → still transformation)
○ Protease (no protein → still transformation)
○ DNase (no DNA → no transformation)
● Hershey-Chase: Confirmed DNA, not protein, as genetic material
○ Used bacteriophages (viruses) to infect bacteria with radioactive DNA or protein.
Found that only the DNA was transferred to the next generation of viruses
* DNA Replication – Prokaryotic:
Steps:
1. DnaA binds to OriC and begins the process
2. Helicase unwinds DNA, SSBs bind to prevent reannealing, DNA gyrase relieves
supercoiling
3. Primase synthesizes primer
4. DNA pol. III binds to primer and synthesizes DNA
5. DNA pol. I removes & replaces the primer
6. DNA ligase seals nicks left by removed primer
● Polymerases also have exonuclease activity → proofreading
● DNA synthesizes 5’ to 3’
○ Leading vs. Lagging (Okazaki fragments)
● DNA housed in the nucleoid, circular
about:blan 2/
k 9
AM each unit
Cell Cycle:
● Interphase:
○ G0: No growth signal is produced
○ G1: Growth signal is produced, and the cell prepares for division
○ S-phase: DNA replicates
○ G2: two centrioles, chromosomes are replicated w/sister chromatids
● Mitosis…
Mitosis:
● Prophase: Chromosomes condense, centrioles divide and begin moving to opposite poles,
nuclear envelope begins to dissolve
● Metaphase: Spindle fibers attach to kinetochore and line up in the middle of the cell
● Anaphase: Sister chromatids separate to opposite poles (disjunction)
● Telophase: Cell splits, nuclear envelopes re-form and chromosomes de-condense
Meiosis:
● Purpose: produces gametes
○ 4n rather than 2n (more genetic material!!)
○ Spermatogenesis = 4 cells w/n chromosomes
○ Oogenesis = 1 egg cell with 2 small polar bodies
● Prophase 1: recombination/crossing over
● Metaphase 1: random alignment
● Anaphase 1: full homologous chromosomes, not sister chromatids
● Telophase 1: cytokinesis with optional interphase
● Prophase 2: Same as mitosis
● Metaphase 2: Same as mitosis
● Anaphase 2: Same as mitosis
● Telophase 2: Results in 4 cells with n chromosomes (haploid)
DNA Structure:
● Practice on paper (+RNA structure)
● Right-handed helix
● Phosphate backbone
○ Hydrophilic
● Phosphodiester bonds
○ Joins two nucleotides
● Major groove: big “gap”
● Minor groove: small “gap”
about:blan 1/
k 9
, 9/17/24, 11:24 BIO 210 Exam Review - Includes items from
AM each unit
DNA Experiments:
● Meselson-Stahl:
○ Models of DNA replication
■ Conservative: replication = original DNA & copy
● 1 band would contain DNA solely composed of old DNA, and the
other would contain DNA exclusively composed of new DNA
■ Dispersive: replication = 2 DNA with patches of old & new throughout
● Prediction: would show intermediate bands where the DNA would
be mixed together in each DNA molecule.
■ Semi-conservative: 2 DNA with one old strand and one new strand
● hybrid band in the first replication, each DNA molecule consisted
of 1 strand of the original DNA and 1 newly synthesized DNA.
● Griffith: establish transforming principle
○ Smooth → mouse dies
○ heat-killed smooth → mouse lives
○ rough → mouse lives
○ heat-killed + rough → mouse dies
● Avery, Mcleod, McCarthy: determine transforming principle
○ Treat heat-killed S with RNase (no RNA → still transformation)
○ Protease (no protein → still transformation)
○ DNase (no DNA → no transformation)
● Hershey-Chase: Confirmed DNA, not protein, as genetic material
○ Used bacteriophages (viruses) to infect bacteria with radioactive DNA or protein.
Found that only the DNA was transferred to the next generation of viruses
* DNA Replication – Prokaryotic:
Steps:
1. DnaA binds to OriC and begins the process
2. Helicase unwinds DNA, SSBs bind to prevent reannealing, DNA gyrase relieves
supercoiling
3. Primase synthesizes primer
4. DNA pol. III binds to primer and synthesizes DNA
5. DNA pol. I removes & replaces the primer
6. DNA ligase seals nicks left by removed primer
● Polymerases also have exonuclease activity → proofreading
● DNA synthesizes 5’ to 3’
○ Leading vs. Lagging (Okazaki fragments)
● DNA housed in the nucleoid, circular
about:blan 2/
k 9
