Cancer
what is cancer?
what are the key events of prophase?
- chromatin is condensed
- nucleoli dissapear
- duplicated chromosomes appear as sister chromatids
- mitotic spindle begins to form and chromosomes move away from each other
What is the definition of the cell cycle?
The life of a cell from its formation until it divides
G1 checkpoint, G2 checkpoint, and M (spindle) checkpoint
What must happen before cell division?
A cell must organize and package its DNA
the uncontrolled growth of cancer cells can lead to a ___?
what is a tumor?
what are the key events of Prometaphase?
- nuclear envelope fragments
- microtubules enter nuclear area and some attach to kinetochores
What is the purpose of the cell cycle?
Reproduction of cells, growth of cells, and tissue repair
Which major checkpoints checks for cell size, growth factors, and DNA damage using the “stop” signal to tell the cell to enter the G0 phase and the “go” signal to tell the cell to complete the cycle?
G1 checkpoint
What is the name of the protein DNA uses to form nucleosomes?
Histones
what is the difference between benign and malignant tumors?
Benign is abnormal but not cancerous cells
Malignant is masses of cancerous cells that can leave the tumor site
What are key events of metaphase?
centrosomes are in opposite poles
- chromosomes line up at metaphase plate
- microtubules are attached to each kinetochore
What are ALL of the stages in the cell cycle in order?
G1, S, G2, Mitosis, Cytokinesis
Which major checkpoints checks for completion of DNA replication and DNA damage using the “stop” signal to tell the cell to stop and attempt to repair any damage and the “go” signal to tell the cell to proceed to mitosis?
G2 checkpoint
What happens to chromatin during DNA replication?
It condenses to form a chromosome
what is the difference between normal and cancerous cells?
cancer cells don't follow checkpoints, they divide infinetley and they evade apoptosis.
what are the key events of anaphase?
- sister chromatids separate and move to opposite ends of the cell due to the micro tubules shortening
- cell alongates
What is the phase called that include stages G1, S, and G2?
Interphase
Which major checkpoint checks for microtubule attachment to chromosomes at the kinetochores at metaphase using the “stop” signal to tell the cell to pause mitosis to allow spindles to finish attaching to chromosomes and the “go” signal to tell the cell to proceed to anaphase to finish mitosis?
M (spindle) checkpoint
What is a centromere?
the region on each sister chromatid where they are most closely attached
how many, on avg, mutations do cancer cells that regulate cell growth accumulate?
60+ mutations on average
what are the key events of telophase and cytokinesis?
telophase: 2 daughter nuclei form, nucleoli reappear, chromosomes become less condensed.
Cytokinesis:
in animals:a cleavage furrow appears due to a contractile ring of actin filimants
in plants:vesicles produced by golgi travel to middle of the cell and form a cell plate.
In which stage does DNA replication occur?
S phase/Synthesis
The internal regulation of the cell cycle requires an internal control system that consists of …
Proteins known as cyclins and enzymes known as cyclin dependent kinases
What is a Kinetochore?
Proteins attached to the centromere that link each sister chromatid to the mitotic spindle