Cell Division Mitosis Flashcards
Test
How many chromosomes do humans have, how many types, & how many of each type?
46 chromosomes, 23 pair types, 2 of each type
How many complete sets of 23 chromosomes
2
Different versions of the same gene:
Alleles
Alleles
Different version of the same gene
Contain the same genes but not genetically identical
Homologous Chromosomes
Homologous Chromosomes
they contain the same genes but are not genetically identical
What is ploidy?
Number of sets of chromosomes in the nucleus; human are diploid
Number of sets of chromosomes in the nucleus
Ploidy
Haploid number
Number of chromosomes in a set
Cell Cycle
events between formation of the cell and division of the cell
How many components are in the cell cycle?
3
What are the components of the cell cycle?
Interphase, Mitosis - Nuclear division, and Cytokinesis
How many stages are in Interphase, and what are they?
There are three stages in interphase, and they go in the order of G1, S, and G2
Describe the first stage of interphase
G1: The cell will grow and continue its normal function, and lots of enzyme production- is necessary for DNA replication.
Describe the second stage of interphase
S: Synthesis - chromosomes replicate into identical chromatids, creating a dyad with a centromere holding them together (kinetochore), and MTOCS replicate, doubling the centrioles.
Describe the last stage of interphase
G2: mitochondria and or chloroplasts divide, massive production of tubulin, and chromosomes begin to coil more.
How many phases are in Mitosis? Name them.
5; 1. Prophase 2. Pro-metaphase 3. Metaphase 4. Anaphase 5. Telephase + Cytokinesis
Describe the first phase of mitosis.
Prophase: Chromosomes become completely condensed, centrioles move to opposite sides of the cells and produce polar microtubules; these produce aster fibers that connect centrioles to cell membrane
Describe the second phase of mitosis.
Pro-metaphase: nuclear membrane degenerates, MTOCs produce kinetochore microtubules
Describe the third phase of mitosis.
Metaphase: K Microtubules arrange with dyads at the center of the cell
Describe the fourth phase of mitosis.
Anaphase: Centromeres break, and chromatids get pulled towards opposite ends of the cell; polar microtubules lengthen, and spindle apparatus: PMicrotubules, AMicrotubules, and KMicrotubules
Describe the fifth phase of mitosis.
Telephase and Cytokinesis: Chromosomes reach ends of cell, nuclear envelope forms spindle apparatus disassembles, chromosomes decondense, belt of actin around metaphasic plate constricts, pinches cell in half, results in 2 daughter cells (2N) that are genetically identical
List some differences in plant cell division
There are no centrioles in MTOC, no aster fiber, and cytokinesis occurs through cell plate; Division starts in the middle and grows out
