Cytokinesis and Key Terms

In animal cells…

-cleavage furrow splits cells

-microfilaments contract (contractile actin and myosin) like a belt until it’s cut into halves

In plants cells…

-cell plate split cells into 2

Describe the steps of splitting plant cells

-vesicles move to equator and fuse to form the cell membrane

-pectin is deposited by exocytosis to form the middle lamella

-cellulose is deposited by exocytosis to form the cell

What is the deposited pectin used for?

to form middle lamella

What is the deposited cellulose used for?

to form the cell

Supercoiling

process that occurs to condense chromatin into chromosomes

-DNA is repeatedly coiled around histone proteins until it becomes shorter and wider to make a chromosome

Chromosome

DNA and histone proteins

Nucleosome

8 histone proteins with DNA wrapped around

Microtubule Organizing Centers (MTOC)

helps form the spindle apparatus in prophase by organizing microtubules (a type of cytoskeleton made with tubulin)

-help centrioles in animal cells

Kinetochore

protein structure that attaches chromosomes to microtubules during cell division

-pull apart sister chromatids in anaphase

Mitosis Index

ratio between the number of cells in mitosis and the total number of observed cells in a tissue sample (number of cells in mitosis/total number of cells)