Lab 6 Flashcards
What are the two main phases of the cell cycle?
The cell cycle is divided into interphase (G1, S, G2) and the mitotic phase.
What is the role of checkpoints in the cell cycle?
Checkpoints regulate the progression through the cycle to ensure proper division.
What are cyclins and CDKs?
Interactions between cyclin and cyclin-dependent kinases are crucial for cell cycle control.
What occurs during the G1 phase?
Cell growth
Restricting cells from passing unless they have all the requirements for division
What happens during the S phase?
DNA replication occurs.
What is the focus of the G2 phase?
Further growth and preparation for mitosis.
Requires a certain number of proteins that will allow for the nuclear envelop to fragment and centrosomes to develop microtubules
What are the stages of mitosis?
Prophase, prometaphase, metaphase, anaphase, and telophase.
What is the purpose of Polymerase Chain Reaction (PCR)?
Used to amplify specific DNA regions using Taq polymerase.
What are the steps involved in PCR?
Denaturation, annealing, and extension.
What is an application of PCR?
Testing for transgenes in genetically modified organisms (GMOs).
What is microscopy used for in cell biology?
Used to identify and count cells in different mitotic stages.
What is DNA extraction?
The process of isolating DNA from cells, a preliminary step in PCR.
What is genetic modification?
The process of altering the genetic material of an organism, often involving the introduction of foreign DNA.
What are transgenes?
Genes that have been transferred from one organism to another, often detected using PCR.
What is the CaMV35S promoter?
A commonly used regulatory sequence in genetically modified organisms, detectable by PCR.
What is Taq polymerase?
A heat-stable enzyme used in PCR to synthesize DNA.
What is denaturation in PCR?
The first step in PCR where the double-stranded DNA is heated to separate into single strands.
What occurs during the annealing step of PCR?
The second step in PCR where primers bind to the single-stranded DNA.
What happens during the extension step of PCR?
The third step in PCR where Taq polymerase extends the primers to form a new DNA strand.
What is the role of helicase in DNA replication?
An enzyme that unwinds the DNA double helix during replication.
What is the function of DNA polymerase?
An enzyme that synthesizes new DNA strands by adding nucleotides complementary to the template strand.
What is the anti-parallel structure of DNA?
The orientation of the two strands of DNA in opposite directions, crucial for replication.
Why do cells divide?
- Growth
- Repair
- Reproduction
What is the cell cycle dependent on?
- The concentrations of cyclin in the cell
- How much cyclin is bound to CDK
What do promoter and terminator sequences do?
They influence when and where a gene will be expressed
Promoter: Helps start the transcription of the gene
Terminator: Stops transcription
In a PCR; what forces the two strands apart vs what would force the strands apart in DNA replication?
In a PCR; temperature forces the strands apart
In DNA replication; helicase would force the two strands apart
What are the features that identify which stage of mitotic division a cell is in?
Prophase: Chromosomes condense and become visible, and the nucleolus disappears.
Metaphase: Chromosomes line up in the middle of the cell at the metaphase plate, and each chromosome is attached to microtubules.
Anaphase: The sister chromatids separate, and the chromosomes move to opposite ends of the cell.
Telophase: Two nuclei form, the nuclear envelope reappears, and DNA de-condenses.
Cytokinesis: The cytoplasm divides, and the cell splits into two separate cells.
What was the researcher trying to discover in the “Identifying Mitotic Stages” lab exersise?
If reagent X had any effect on the rate of cell division in cells grown in tissue culture
