Mitosis Flashcards
In which part/s of the cell is the DNA found?
Nucleus and Mitochondria
Describe structure of DNA (5)
1) Double Helix
2) CBP
3) Coils around nucleosomes
4) Coils into Supercoils
5) Coils into Chromosomes
Names for G Banding and Q Banding?
Which arm is short?
Giesma, Quinacrine
P arm is short
What is mitosis for? (3)
1) Replace dead cells 2) Growth
3) Produce 2 daughter cells (One somatic into 2)
How long does mitosis occur for?
Mitosis is 1 hour cycle (Interphase 23)
What is G0?
Stable cells that don’t divide (e.g. Liver)
Steps of Interphase?
DNA replication, cell growth then Centrosome replication
First 2 stages of Mitosis?
1) Prophase: Chromatin condense and centrosome to opposite poles of Nucleus
2) Pro-Metaphase: NM bdown and chromatids attach to microtubules
What happens in last 3 stages?
T: NCC
1) Metaphase: Chromosomes line up along EP
2) Anaphase: SC separate, and push to opposite ends (MT scaffold shortens)
3) Telophase: NM reform, chromosomes unfold, cytokinesis
Clinical relevance of Mitosis? (2)
1) Detecting Chromosomal abnormalities
2) Categorising and grading (M) tumours
Meiosis differences? (4)
1) Only in Gametes
2) 4 Haploid produced
3) 2 cell divisions
4) Recombination of genetic material
How is sperm produced?
Bonus on how does the cytoplasm divide
From primordial germ cells, lots of mitoses lead to Spermatogonia (Cytoplasm divide evenly)
How are eggs produced?
Bonus on cytoplasm divide?
Primordial germ cell, 30 mitoses leads to oogonia
cytoplasm unevenly divide into 1 egg and 3 polar bodies
What is Non-disjunction?
Failure of chromosomes to sep in M1, or SC to sep in M2
What is Gonadal Mosaicism?
Involves spermatozoa or ova
PGC are a mixture of 2/more genetically different cell lines (1 normal and 1 mutated)
