Mitosis and cell cycle
What are parent and daughter cells?
Parent cell: the original cell that undergoes division
Daughter cell: the two genetically identical cells that result from mitosis
What is kinetochore and kinetochore microtubules?
Kinetochore: protein complex on the centromere where spindle fibers attach
Kinetochore microtubules: attach to kinetochores and pull chromosomes to the poles
What is density dependent inhabitation?
Cells stop dividing when they become too crowded
What are homologous chromosomes and sister chromatids?
Homologous chromosomes: a pair of chromosomes of the same type, same genes, different alleles
Sister chromatids: Identical copies of a chromosomes after replication.
What is a paternal gamete and a Recombinate gamete?
Paternal: has chromosome combination exactly like its parents
Recombinate: has a new combination of maternal and paternal alleles due to crossing over
What is a diploid and a haploid?
Diploid: two sets of chromosomes
Haploid: one set of chromosomes (haploid)
What stages happen in interphase and mitosis?
Interphase: G1, S, G2
Mitosis: prophase, pro metaphase, metaphase, anaphase, telophase, cytokenisis
What is anchorage dependence?
Cells must be attached to a solid surface to divide
What is a tetrad and chiasma?
Tetrad: a paired group of four chromatids (2 homologous chromosomes, each duplicated)
Chiasma: physical point where non sister chromatids cross over
What is a Recombinate chromosome?
a chromosome that contains DNA sequences from both maternal and paternal origins due to crossing over
What are sister chromatids?
Two identical DNA copies attached at the centromere after replication
What is being evaluated at the G1 checkpoint?
-DNA integrity
-If growth factors are present
What is a gamete?
a haploid reproductive cell produced by meiosis, contains one set of chromosomes.
What is crossing over?
Non sister chromatids exchange DNA and produces Recombinate chromosomes with allele combinations not found in the parents
How many chromosomes or chromatids are there before replication, after replication, and after mitosis?
Before:46 chromosomes
After replication:46 chromosomes, 92 chromatids
After mitosis: each daughter cell has. 46 chromosomes
What is being evaluated at the G2 checkpoint?
-Successful DNA replication
-No DNA damage
-Cell size
What is the purpose of meiosis?
To produce haploid gametes for sexual reproduction
Identify the policy at all three stages
Before meiosis: 2n, duplicated
After meiosis 1: n, duplicated
After meiosis 2: n, unduplicated
How does independent assortment create variation?
Each homologous pair aligns independently, each gamete receives a random mix of maternal and paternal chromosomes
What are growth factors?
protein/signals that encourage cell division, without them most cells will not divide
What is being evaluated at the M checkpoint?
-If the kinetochores are properly attached to spindle fibers
What is the difference between mitosis and meiosis?
Mitosis: 1 division, 2 genetically identical diploids
Meiosis: 2 divisions, 4 genetically unique haploid gametes, reduces chromosome number
The random orientation of maternal vs paternal homologs during metaphase 1