Mitosis and Meiosis Flashcards
What are the 4 phases of cell cycle?
G1, S, G2, M
G1, S, and G2 are the interphase
How much time does a cell spend in the interphase?
90%
What is a chromosome?
A molecule of DNA and the associated proteins
What is a chromatid? What are sister chromatids?
One of the duplicated copies of DNA. Sister chromatids are identical to each other
How many chromosomes are in a pair of sister chromatids?
1
What is a centromere?
Region of DNA where sister chromatids are attached
What is the kinetochore?
The proteins attached to the centromere
What is a karyotype? What distinguishes chromosomes?
An image of chromosomes during metaphase. Size, centromere position, secondary constriction, and banding patterns
What are the 3 centromere positions?
Metacentric: in the middle
Acrocentric: not in the middle, one arm is shorter than the other
Telocentric: at the telomere
What is a secondary constriction?
Places where transcription is occurring, but RNA and proteins aren’t on the karyotype
What is mitosis?
An equational division that gives two daughter cells with the same ploidy as the original cell
What are the phases of mitosis?
Prophase, metaphase, anaphase, telophase, cytokinesis
What happens in prophase of mitosis?
Sister chromatids condense, mitotic spindle begins to form, the mass of chromatin becomes distinguishable chromosomes
What occurs in prometaphase of mitosis?
The nuclear envelope breaks apart, sister chromatids finish condensing, mitotic spindle finishes, microtubules attach to the kinetochores
What occurs in metaphase of mitosis?
Chromosomes line up along the metaphase plate in the middle of the cell