Define cell cycle.
The series of events that take place in a cell leading to its division and replication.
What are the main phases of the cell cycle?
Interphase, mitosis, and cytokinesis.
True or false: The G1 phase is part of interphase.
TRUE
G1 phase is the first stage of interphase where the cell grows and prepares for DNA replication.
Fill in the blank: Mitosis results in _______ daughter cells.
Two genetically identical
What occurs during the S phase?
DNA replication takes place, resulting in two copies of each chromosome.
Define cytokinesis.
The process where the cytoplasm divides, resulting in two separate cells.
True or false: G2 phase follows mitosis.
FALSE
G2 phase occurs after the S phase and before mitosis.
What is the role of checkpoint proteins?
They monitor the cell cycle and ensure proper progression and repair of DNA damage.
Define apoptosis.
Programmed cell death that eliminates damaged or unnecessary cells.
Fill in the blank: The M phase includes _______ and cytokinesis.
Mitosis
What is the purpose of the G1 checkpoint?
To assess cell size, DNA integrity, and nutrient availability before DNA synthesis.
True or false: Interphase is the longest phase of the cell cycle.
TRUE
Interphase can last for hours to days, depending on the cell type.
What happens during prophase?
Chromatin condenses into chromosomes, and the nuclear envelope begins to break down.
Define metaphase.
The stage where chromosomes align at the cell’s equatorial plane before separation.
Fill in the blank: During anaphase, sister chromatids are pulled _______.
Apart to opposite poles
What is the role of spindle fibers?
They help separate chromosomes during mitosis.
True or false: Telophase is the final stage of mitosis.
TRUE
Telophase involves reformation of the nuclear envelope around separated chromosomes.
What is a cyclin?
A protein that regulates the cell cycle by activating cyclin-dependent kinases (CDKs).
Define CDK.
Cyclin-dependent kinase, an enzyme that, when activated by cyclins, drives the cell cycle forward.
Fill in the blank: Cancer can result from _______ in cell cycle regulation.
Mutations
What is the significance of the G2 checkpoint?
It checks for DNA damage and ensures all DNA is replicated before mitosis.
True or false: Cells can skip the G1 phase.
TRUE
Some cells, like neurons, may exit the cell cycle and enter a quiescent state.
What is binary fission?
A form of asexual reproduction in prokaryotes where a cell divides into two identical cells.
Define chromatid.
One of the two identical halves of a replicated chromosome.
