Mitosis and cytokinesis (week 2)

What happens during interphase?

Occurs before mitosis and cyclin concentration must reach its threshold. Very active phase of cell with many processes occurring. Cytoplasm increases, mitochondria and chloroplasts replicate, new cell walls and dna replication. Chromosomes are single armed structures in unwound state.

What happens in prophase?

Chromatin condenses into sister chromatids (visible under microscope), centromeres move to opposite ends, nuclear membrane disappers

What happens in metaphase?

Spindle fibres from each centrosomes to the centromere of each pair of sister chromatids. Contraction of microtubles cause sister chromatids to line up along the equator.

What happens in anaphase?

continued contraction of microtubules cause sister chromatids to separate. Chromosomes move to opposite ends of the pole.

What happens during telophase?

two chromosomes condense into chromatin. Microtubule fibres disappear, nuclear membrane forms

What happens during cytokinesis? explain for plants and animals

occurs after mitosis. In animals the plasma membrane is pulled in and around equator of cell to form cleavage furrow by proteins. In plants vesicles move to the equator fuse to form tubular structure which which merges with more

vesicles to form the plasma membrane and divide the cytoplasm. Substances such as pectin and cellulose are then deposited by exocytosis to form the lamella and cell wall.

What is the purpose of mitosis?

it is the splitting of the genetic material and the splitting of the nucleaus