M2 chapter 6- cell divison Flashcards
why do we need new cells?
growth and repair
what are the stages of mitosis?
prophase
metaphase
anaphase
telophases
(interphase and cytokinesis aren’t technically part of mitosis)
what is the m phase of cell division?
mitosis and cytokinesis
what 3 stages is interphase in?
G1,s, G2
how is the cell cycle regulated?
checkpoints that occur at key points to ensure the process is okay to continue
what happens in interphase?
cell gets ready to divide
cells dna is unravelled and replicated
organelles are also replicated
atp content is also increased
what is misosis?
1 cell divided to become 2 cells
some organisms use this to reproduce asexually
is a continuous process
what are the structure of chromosomes in mitosis?
made of 2 strands joined in middle by centromere
separate strands are chromatids
has 2 strands because each chromosome has an identical copy of itself during interphase
how are the chromosomes arranged after mitosis?
when mitosis is over chromatids and up as 1 single strand in new cells
what happens in prophase?
chromosomes condense
centrioles move to ends of cells to create spindle fibres
nuclear envelope breaks down
chromosomes are free in the cytoplasm
what happens in metaphase?
chromosomes line up along equator of cell
they attached to the spindle by centromere
at this checkpoint cell checks all chromosomes are attached to spindle before it continues
what happens in anaphase?
centromeres move apart separating each pair of sister chromatids
spindles contract pulling chromatids to opposite ends of cell
what happens in cytokinesis?
cytoplasm divides and cleavage furrow forms to divide the cells, creating 2 identical daughter cells.
this process begins in anaphase and ends in telophase
what happens in telophase?
chromatids reach opposite poles and uncoil to become chromosomes. the nuclear envelope then forms
what is different about cytokinesis in plants compared to animals?
it is initiated by the formation of a cell plate in the middle of the cell.
how would you observe mitosis scientifically?
treat tips of roots in HCL and break them open then spread a few on a slide and view them under a microscope. because the roots are part of a plant that keeps on growing
what are sperm and egg cells?
gametes
what is a cell with 2 of each chromosome called?
diploid
how is genetic differentiation created?
chromosomes that make up each pair are the same size and have same genes however could have different versions of genes aka alleles
what are gametes?
haploid cells
what is meiosis for?
cell division to produce gametes which are all genetically different
what happens in interphase in meiosis?
dna unravels and replicates to produce double armed chromosomes, sister chromatids