Chapter 18 Flashcards
Cells divide to copy and pass on what?
Genetic Information
Cell cycle time/duration reflect what?
The amount of DNA in a cell (and the functional role of the cell
In the M Phase of the cell cycle, what happens?
The nucleus and the cytoplasm both divide
What is the process of nuclear division called?
Mitosis
What is the process of cytoplasmic division called?
Cytokinesis
During Interphase, what happens?
Continuous Cell Growth in preparation for cell division
DNA is replicated
What are the 3 stages of Interphase called?
G1, S, and G2
What happens during the G1 phase?
- Cell grows
- Organelles are duplicated
- Cells prepare for DNA replication
- Gap forms between the M phase and S phase
What happens during the S phase?
1.DNA Replication
2. Chromosomes are duplicated forming sister chromatids
What happens during the G2 Phase?
More cell growth
- Gap forms between the S phase and the M phase
What are the 3 requirements for Cell Divisions to occur?
- There must be sufficient nutrients in the environment
- Chromosomes must be accurately replicated
- Chromosomes must be aligned to separate properly
What do Protein Kinases do in regard to the Cell Cycle?
Assists in the regulation of the cell cycle
What do Cyclin Dependent Kinases do in regard to the cell cycle?
they initiate the cell cycle via phosphorylation
How do Cdk’s get activated?
They bind Cyclin and become activated
What causes cell cycle arrest? (2)
- conditions result in cell stopping and not proceeding through cycle
- Cdk inhibitor protein blocks cyclin-Cdk complex assembly
What happens when cell stops dividing during cell arrest?
Stage G0; a modified G1 state where Cdks/Cyclins disappear
What is the most common form of Programmed death?
Apoptosis
What is Apoptosis?
Programmed Cell Death
Why is Apoptosis necessary?
Rids cells that are no longer necessary
-it sculpts organism during development
What is the difference between Apoptosis and Necrosis?
Apoptosis: cells shrivel/shrink and condense
Necrosis: cells swel/burst
What triggers Apoptosis?
CASPASE