Cell Cycle MItosis, Meiosis Video Flashcards
What is a diploid cell
A cell that has 2 complete sets of chromosomes (2n)
What is a haploid cell
One copy of DNA (sperm and egg cells)
Does Mitosis deal with diploid of haploid cells
Diploid
What are the 2 parts of cell division
- Mitosis - division of nucleus
2. Cytokenisis - divison of the rest of the cell organelles
What phase is most of the life of a cell spent in
Interphase
which includes G1, S, & G2 phases
What is the G1 phase
Growth phase
What is the S phase
Phase where DNA replication occurs
What is the G2 phase
Continued growth of cell
What is CDK - Cyclin Dependent Kinase
Speeds up action in cell growth
What are the identical sides of a chromosome called
Chromatin
What is the middle of a chromosome called
Centromere
What are the phases of Mitosis
Interphase Prophase Metaphase Anaphase Telephase Cytokenisis
What occurs during Prophase
Chromatin has become chromosomes Centrosomes begin to seperate Miotic spindles begin to form Nuclear envelope disassembles Chromosomes form two kinetochores at centromere Microtubules attache to chromosome
What occurs during Metaphase
Chromosomes align in middle of the cell
What occurs during Anaphase
Chromatids seperate towards opposite sides
What occurs during Telophase
New nuclear envelope forms
Chromosomes unfold back into chromatin
Nucleoli reappear
Cell continues to elongate
What happens during Cytokenisis
Daughter cells divide and cell cycle repeats again
What is a homologous chromosome
Chromosomes that are the same length but don’t do the same thing. One could be recessive and the other could be dominant
What is the goal of mitosis
Make an exact copy of the nucleus
What is goal of meiosis
Make genetically different cells
What is cancer caused by
Uncontrolled cell division
Explain the difference between a proto-oncogene and a tumor suppressor gene.
A proto-oncogene is the segment of DNA that codes for one of the positive cell-cycle regulators. If that gene becomes mutated to a form that is overactive, it is considered an oncogene. A tumor suppressor gene is a segment of DNA that codes for one of the negative cell-cycle regulators. If that gene becomes mutated to a form that is underactive, the cell cycle will run unchecked
Outline the steps that lead to a cell becoming cancerous.
If one of the genes that produce regulator proteins becomes mutated, it produces a malformed, possibly non-functional, cell-cycle regulator. This increases the chance that more mutations will be left unrepaired in the cell. Each subsequent generation of cells sustains more damage. The cell cycle can speed up as a result of loss of functional checkpoint proteins. The cells can lose the ability to self-destruct.
________ are changes to the nucleotides in a segment of DNA that codes for a protein.
Gene mutations
A gene that codes for a positive cell cycle regulator is called a(n) ________.
proto-oncogene
A gene that codes for a negative positive cell cycle regulator is called a(n) ________.
Tumor supressor genes
What are Oncogenes
genes that cause a cell to become cancerous
