3.4 Cell Division Part 2 Flashcards
When can cells decide to enter G0?
during G1
What is G0 phase?
cells become quiescent/silent
Why would cells enter the G0 phase?
lack of nutrients or growth factors
What are cells doing in G0?
metabolically active and alive but not continuing on with the cell cycle
What can cause a cell to reenter the cell cycle from G0?
return of nutrients or growth factors
Which type of cells typically rush through G1 and skip G0?
cancer cells
What are the chromosomes doing during interphase?
dispersed throughout the nucleus; not visible via microscopy
What is the longest phase of mitosis?
prophase
What happens during prophase?
chromosomes start condensing and coiling
centrioles migrate to the ends of the cells
What are centrioles?
cytoplasmic bodies that occur in pairs and are found near the nuclei
What is responsible for the formation of spindle fibers during prophase?
centrioles
What are spindle fibers?
needed for the movement of chromosomes through the cell during cell division
What are spindle fibers composed of?
tubulin
What cells are centrioles found in?
animal cells
What occurs at the same time as centrioles migrate to their respective ends of the cell?
nuclear envelope disintegrates
chromosomes start to condence
What do chromosomes look like by the end of prophase?
condensed X shapes structures
What are sister chromatids?
two parts of the X of each chromosome
How are sister chromatids held together?
centromere
What is the DNA like for each sister chromatids?
identical
When is cohesin formed?
S phase
