Interphase
Where a cell spends most of its life; period of cell
growth; cell carries out normal functions; DNA
copies
Mitosis
Division of chromosomes so each new cell has the
same genetic information;
has stages:
Prophase/Metaphase/Anaphase/Telophase
Cytokinesis
Division of cytosol; cell splits creating 2 identical
cells
Chromatin
DNA helix wrapped around special proteins;
“stringy” appearance; enables genes to be
transcribed at the start of protein synthesis
Sister Chromatids
2 identical halves of a replicated chromosome;
separated during anaphase
Centrioles
Organelles that help form and support the spindle
fibers
Centromere
The place where two sister chromatids are held
together
Prophase
Sister chromatids become visible; centrioles migrate
to opposite poles; spindle fibers form; nuclear
envelope breaks down; complete when centrioles
reach the poles
Metaphase
Chromosomes line up in a straight line in the
middle of the cell
Anaphase
Sister chromatids are pulled apart
Telophase
Cell is starting to pinch in wo
t
Spindle Fibers
Protein fibers that pull chromatids apart during
anaphase
Diploid
Cells with the total chromosome number
(humans=46)
Haploid
Cells with half the normal chromosome number
(humans=23); half
Homologous Chromosomes
In each pair, one chromosome is from mom and one
is from dad; carry genes for the same traits
Crossing over
Exchanging of genetic material
Meiosis
Occurs in the ovaries and testes and produces eggs
and sperm; starts with a diploid germ cell and ends
with haploid sex cells
Apoptosis
Programmed cell death
Growth Factors
Proteins that can act as a trigger for cells to divide;
“green lights”
Nondisjunction
When chromosomes fail to separate correctly during
anaphase