mitosis Flashcards
what type of cells enter mitosis?
eukaryotic
what are the 2 types of nuclear division?
mitosis and meiosis
what are the 5 stages of mitosis?
interphase, prophase, metaphase, anaphase, telophase/cytokinesis
describe prophase
chromosomes condense. Nuclear membrane breaks down. Centrioles separate, move to opposite poles and create spindle fibres-create a spindle apparatus. Plants don’t have centrioles
describe metaphase
the chromosomes align along the metaphase plate (equator). Spindle fibres released now attach to centromere and chromatids.
describe anaphase
spindle fibres contract and pull centromere & chromatids to opposite poles. This causes the centromere to divide into 2. This requires ATP provided by mitochondria.
describe telophase/cytokinesis
Chromosomes become longer and thinner as they uncoil. SF disintegrate and nuclear envelope and nucleus starts to reform around each group so two nuclei are present. Cytoplasm splits into 2 to create 2 new genetically identical daughter cells (cytokinesis)
what are the 3 stages in interphase?
gap phase1, synthesis and gap phase 2
describe Gap phase 1
cell grows and new organelles and proteins are made. RNA, enzymes etc are made
describe synthesis in interphase
cell replicates its DNA ready to divide by mitosis
describe Gap phase 2 in mitosis
cell keeps growing and proteins needed for cell division are made
how do you calculate mitotic index?
number of cells undergoing division in field of view divided by total number of cells in field of view
Describe interphase
The cell is carrying out its normal functions but is also preparing to divide. The DNA is unravelled and replicated and organelles are replicated. ATP production increases as it provides the energy needed for cell division