Quest II Flashcards
Chromosones
tightly compacted structures of DNA
Chromosome structure
rod shaped structures of DNA and histones (proteins) found in a cells nucleus
Each half a a chromosone is called a
Chromotid
Autosomes have _____ chromosomes
44 (22 pairs) + 1 pair of sex chromosomes
46 chromsomes
Autosomes determine
Personality and physical traits
Homologous Chromosomes
same size, shape, and carry genes for the same traits
Karyotype
a display of our 22 pairs of homologous autosomes
+
1 pair os sex chromosones
Diploid
= double
cells havng 2 sets of chromosomes (2n)
All cells in your body are diploid except your
sex chromosones
Haploid
cells having only 1 set or 1/2 of the chromosomes.
this = sperm and egg cells
binary fission
the division of one cell into 2 new offspring cells. no chromosomal variation
Asexual reproduction
one parent is involved (prokaryotes) less genetic variation
Sexual reproduction
2 parents involved (eukaryotes) more genetic variation 99.9% idntical
Mitosis
process of cell division resulting in 2 new cells with the identical # of chromosomes s the original cell (bodycells/2n)
+____+
Interphase, prophase, metaphase, anaphase, telaphase, and cytokenesis
Interphase
the time between new cell divisions 90%
carries out specific function
prepares for new cell division
Prophase
DNA shortens and coils into chromosomes
nucleolus and nuclear membrane disapear
centrsomes appear and move to opposite poles of the cell
92 chromosomes
As the centrosomes move apart in prophase
spindel fibers (microtubles) radiate out from each centrosome
metaphase
Spindle fibers move the chromosomes, all 92, to the center of the cell and hold them in place
Anaphase
Chromatids of each chromosome separate at the centromere and slowly move to opposite poles of the dividing cell
Telephase
spindle fibers disassemble, the nucleolus and the nuclear membrane reapear and the chromosomes return to a less coiled state
cytokenesis
splitting of the cytoplasm
2 new cells
proteins
regulate the process of cell division at interphase
Meiosis
the process o cell division that reduces the # of chromosomes to 1/2 the orignal amount and creates sex cells (gametes