Mitosis and Meiosis Flashcards
Parts of mitosis by order
Prophase
Metaphase
Anaphase
Telophase
The chromosome has two …
Chromatids
How many telomeres are in a chromosome?
4
G1
Amount of chromosomes-n and DNA-c
2c, 2n
S phase
Amount of chromosomes-n and DNA-c
4c, 2n
Atypical Mitosis - what is different from the typical
Different cells outcome or Mosaicism
What is an hallmark of an endomitosis?
Giant cell - polythene chromosome
Tripolar metaphase - which cells?
Tumor cells
Anaphase lag -
Error - Loss of chromatid during mitosis by lack of kinetochore attachment
Non-disjunction
Causes Aneuploid cells formation: Two mitotitc microtubule from the same side attach to the same chromosome
Could yield Down syndrome
Bridge formation
Attachment to same chromatid from opposing side - yields fragmentation
Non disjunction of all 23 chromosome will cause what number of n in each cell?
In the losing side 2(n-1)
In the winning side 2(n+1)
What is the change in c (dna amount ) in meiosis?
2c-4c-2c-1c
By the end of meiosis 1, what is the number of n?
1n
By the end of meiosis 2, what is the number of n?
1n
When does crossing over occurs?
Prophase 1 - Pachytene
Homologous chromosomes -
Same genes different alleles
Parts of prophase 1 - Leptotene
Standing next to each other
Parts of prophase 1- Zygoten
Synapse between the homologous chromosomes
Parts of prophase 1- Peachyten
Exchange of genetic material as crossing over - homologous recombination
Parts of prophase 1- Diplotene
Attachment after crossing over (chiazmma)
Parts of prophase 1- Diakenesis
Further chromosome condensation
Number of human gene variation in homologous recombination?
2^23
How many genomes are there in a diploid cell?
2
