U3P2 Flashcards
steps of mitosis
prophase, metaphase, anaphase, telekinesis
prophase
chromosomes coil up into short rods
cytokinesis
what happens in eukaryotic cells after nucleus divides
metaphase 1
stage of meiosis during which homologous pairs line up along the equator of the cell
meiosis
guarantees number of chromosomes in gametes is half the number of chromosomes in body cells
crossing over
exchange of corresponding segments of DNA that occurs during synapsis
haploid cells
1n, cells resulting from meiosis in either males or females
result of normal mitotic division
two identical daughter cells
mitosis
division of cell’s nucleus
genetic variation
result of crossing over during meiosis
how many autosomes and sex chromosomes in each cell of human body
22 pairs autosomes, 2 sex chromosomes (determine m/f)
of total chromosomes in body cells if diploid 60
60
metaphase 1 of mitosis
homologous pairs present
how does DNA compact
wraps tightly around histones
metaphase
arrangement of all chromosomes along equator
haploid (1n)
contains one copy of a chromosome- either mom or dad j
diploid (2n)
contains two copies of each chromosome, one mom and one dad
tal chromosomes in body cells in organism that has haploid 40
80
difference between anaphase of mitosis and anaphase 1 of meiosis
anaphase of mitosis centromere divides
anaphase 1 pairs divide and move one centromere intact
what would happen if chromosome number not reduced before sexual production
offspring chromosome # would double compared to parents
sexual reproduction
two parents, offspring genetically different, requires meiosis
asexual reproduction
one parent, offspring identical, requires mitosis
following replication of its DNA
each chromosome contains two chromatids, which are attached to each other by a centromere
cancer
caused by mutation in DNA
2n-> 2n 2n
mitosis
why are muscle cells different from nerve cells
express different genes
cell differentiation
process enabling cells to become specialized
epigenome
role environment plays in affecting our genomes
