Chapter 6.1 Flashcards
Cell cycle
What is cell cycle?
Is the highly ordered sequence of events like that take place is a cell resulting does the division of the cell and the formation of two genetically identical daughter cells.
What is the interphase?
Are the short periods that cells go through dormant and go through normal working separate divisions.
{cells spend of majority of it’s time in this phase}
What happens during inter-phase of the cell?
- cells carry out all their major functions: such as reacting with enzymes or hormones (very active phase of the cell cycle)
- cells preparing for the active cell division
What are the 2 main phases of cell cycle?
Mitotic (division) phase
Interphase
What happens during interphase?
- DNA is produced and checked for any errors in the nucleus
- Protein are synthesis stops in the cytoplasm
- Mitochondria grow and divide, increasing the number of the cytoplasm
- Chloroplast grow and divide , increasing the number of the cytoplasm.
- The normal metabolic processes of the cell start to occur.
What are the three stages of interphase?
G1 - first stage is the growth stage: were proteins from which organelles are combined are produced and
organelles break down. Cell size increases.
G2 - Synthesis phase: DNA is replicated in the nucleus.
G3 - The second growth phase: Cell continues to increase in size. DNA that is duplicated is checked for errors.
What are the 2 stages of mitotic phase?
Mitosis
Cytokineses
What is cytokineses?
The cytoplasm divides
What does G(0) mean?
The name that is given to the phase when the cell leaves the cycle for other uses
Why do cells enter the G(0) phase?
Differentiation - when cell becomes differentiated it can no longer be able to divide in many cases and will carry out a function definitely and usually enter the cell cycle again
Aging - as you age the number of cells in the body increases. And a growing a number of senescent cells.
DNA becoming damaged - when cells get damaged they can divide therefore enters a permanent cell arrest (GO)
What is the purpose of checkpoints during the cell cycle?
They are control mechanisms of the cell cycle that monitor and control the process at each phases of the cell cycle have been completed before the cell is allowed to progress into the next phase.
What does happens to the cell during the G(1) checkpoint phase? When does it happen?
- Checkpoint happens after the end of the G(1) phase before the exit from S phase
- If cell satisfy the requirements of the G(1) checkpoint phase it triggers protein synthesis. If not triggered it enters the G(0) phase.
What happens to the cell during the G(2) checkpoint phase? When does this phase happens?
- The checkpoint happens at the start of the G(2) phase before the start the interphase phase.
- After the cell passes the checkpoint to be passed the cell has to check a number of factors. If checkpoint is passed the cell initiates the molecular processes that cell the beginning of mitosis.
The happens at the metaphase checkpoint?
This checkpoint is at the point in mitosis where all chromosomes separate into spindles
What does benign mean?
This means that they actively growing and can travel to other locations in the body
