mitosis

stages of mitosis

which cells does mitosis occur in?

all body cells except sex cells

uses for mitosis?

growth, repair, asexual reproduction (plants)

what are the products of mitosis?

two daughter cells that are genetically identical to each other and the parent cell

stages of the cell cycle in order

interphase, prophase, metaphase, anaphase, telophase, cytokinesis

which stages are not part of mitosis?

interphase, cytokinesis

main aim of interphase

to replicate DNA and make proteins

phases of interphase

G1, S, G2

what happens in G1?

cell/cytoplasm grows, proteins made

what happens in the S phase?

DNA is replicated

what happens in G2?

cell growth, proteins made

what does the genetic information look like during interphase?

chromatin- chromosomes are not visible

what happens to the nucleus in prophase?

the nuclear membrane and nucleolus break down

behaviour and appearance of chromosomes in prophase?

chromatin condenses to form visible chromosomes, chromosomes appear as sister chromatids joined by a centromere

why might the genetic information still look like chromatin (long, linear) in prophase?

the chromosomes aren’t visible as they’re still condensing

what else happens during prophase?

centrioles move to the poles of the cell and spindle fibres develop from them

are centrioles essential to spindle fibres? why?

no, because plants lack centrioles but still develop spindle fibres

what happens in metaphase?

chromosomes line up at the equator of the cell, spindle fibres attach to the centromere of the chromosome

behaviour and appearance of chromosomes in anaphase?

centromeres divide, spindle fibres pull sister chromatids to the poles of the cell

is anaphase an active or passive process?

active

where does the energy for anaphase come from?

mitochondria, which gather around the spindle fibres

behaviour and appearance of chromosomes in telophase?

chromosomes unwind into chromatin

what happens to the spindle fibres during telophase?

they disintegrate

what happens to the nuclear membrane and nucleolus during telophase?

they reform around the two sets of chromatin (forming a cell with two nuclei)

what happens during cytokinesis?

the cytoplasm divides