CHAPTER 2 Flashcards
what is mitosis
when the genetic material in a cell is doubled and then the cell splits into two identical nuclei
what happens in stage 1 of the cell cycle
the cells grow and increase their mass DNA is replicated to form two sets of chromosomes. increased numbers of mitochondria ribosomes and chloroplasts
what happens in stage 2 of the cell cycle
mitosis: one set of chromosomes is pulled to each end of the dividing cell and the nucleus divides
what happens in stage 3 of the cell cycle
the cytoplasm and cell membrane divide to form two identical daughter cells
what is a stem cell
an unspecialised cell
when do most animal cells differentiate
early stages of life
what can embryonic and adult cells do
embryonic stem cells and adult stem cells can be cloned and made to differentiate into different types of cells
examples of conditions that may be helped by stem cells
paralysis and diabetes
problems with embryonic stem cells
ethical come from aborted embryos
progress is slow and expensive
they grow and divide rapidly -> cancer ?
how many chromosomes are in each cells nucleus
46 arranged in 23 pairs
what is the cell cycle
how body cells divide
why is mitosis important
growth repair and development
what is differentiation
when a cell becomes specialised to carry out a particular job
what do adult stem cells do
replace cells that cant divide like rbcs and skin cells
when can most plant cells differentiate
all through their lives