Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
52 Cards in this Set
- Front
- Back
|
are usually a single nucleic acid molecule, largely devoid of associated proteins, and are smaller than eukaryotic chromosomes
|
bacterial and viral chromosomes
|
|
|
can be single or doble standed DNA or RNA
|
chromosomes of viruses
|
|
|
are doble stranded DNA and is compacted into a nucleoid
|
bacterial chromosomes bcs they do not have nucleous
|
|
|
?
|
?
|
|
|
?
|
?
|
|
|
cut one or both DNA strands and wind or unwind the helix before resealing the ends
|
Topoisomerases (DNA gyrase is an example)
|
|
|
Eukaryotic chromosomes are complexed into a nucleoprotein structure called
|
chromatin
|
|
|
Chromatin is bound up in nucleosomes with
|
histones
|
|
|
Type of histones
|
H2A, H2B, H3, and H4 (2 of each)
|
|
|
Nucleosomes are condensed several times ot form
|
the intact chromatids
|
|
|
Nucleosomes are condensed several times ot form
|
the intact chromatids
|
|
|
8 proteins + DNA =
|
nucleosome
|
|
|
Slide
|
page 2
|
|
|
Why chromatin remodeling must occur?
|
to allow the DNA to be accessed by DNA binding proteins
|
|
|
diameter of doble helix
|
2nm DNA naked no protein around
|
|
|
fiber-nucleosomes-mostly uncompacted
|
10nm
|
|
|
fiber-silenoids
|
30 nm
|
|
|
chromatin fibers-looping
|
300 nm
|
|
|
mitotic-fiber-cromatid/chromosome
|
700 nm
|
|
|
Euchromatin is ____ and _____, whereas _____ remains condensed and inactive.
|
uncoiled (10-30 nm)
active condensed inactive |
|
|
characteristic of mitotic (700 nm)chromosomes
|
banding pattern
|
|
|
reflects the heterogeneity and complexity of the chromosome
|
differential staining
|
|
|
repetitive DNA stains
|
dark
|
|
|
Light sections
|
active DNA
|
|
|
highly repetitive and consit of short repeated sequences
|
satellite DNA
|
|
|
are primary constriction anlong eukaryotic chromosomes and mediate chromosomal migration during mitosis and meiosis
|
centromeres
|
|
|
around 30% fo DNA is
|
highlyrepetitive and moderately repetitive
|
|
|
leads to the production of gametes
|
meiosis
|
|
|
leads to productionof two cells
|
mitosis
|
|
|
DNA resides in _____ and organelles in ____
|
nucleus
sytoplasm |
|
|
Cell is surrounded by
|
plasma membrane
|
|
|
plant and bacterial cells also have ___ ___ composed by cellulose and peptidoglycan, respectivelly
|
cell wall
|
|
|
all the ribosomal RNA genes moderately repetive
|
in nucleolus
|
|
|
Karyokinesis
|
nucleous division
|
|
|
cytokinesis
|
division of cytoplasm
|
|
|
During ____ phases of the cell cycle, thise fibers are uncoilded and dispersed into chromatin
|
nondivisional
|
|
|
chromosomes are visible only during _____ and meiosis because ____
|
mitosis
meiosis fibers that make up chromosomes coil and condense in these stages |
|
|
Includes S phase and two gap phases
|
interphase
|
|
|
phase that DNA gets synthesized
|
S phase
|
|
|
G0 cells are dividing cells
|
no
|
|
|
phase where cells withdraw form the cell cycle and enter a nondiving but metabolically active site (S phase)
|
G1
|
|
|
phase where everything in cytoplasm has to duplicate for cell division is when cell is pregnant
|
G2
|
|
|
chromatin fivers coil and condense to form _____ during mitosis and meiosis
|
chromosomes
|
|
|
they are in the cytoplasm, in the centrosome, they organize spindle fibers for movement of chromosomes during meiosis and mitosis
|
centrioles
|
|
|
in each ______ pair of chromosomes, one member is derived from each parent
|
homologous
|
|
|
An organism can be
2x 3x 4x etc |
diploid-all animals have aach chromosome there is a homologous pair
triploid- 3 homologous pairs tetraploid |
|
|
short arm
|
p
|
|
|
long arm
|
q
|
|
|
ends in linear chromosomes
|
telomeres
|
|
|
found in telomeres and centermeres, not for encoding, hold molecules together
|
unknown DNA
|
|
|
Hunintons disease
|
affects huntinon gene
triplet of nucleotides sequences that repeat less than 30 neurological disease affects cognition,mobility, judgement, died at young age. 30-50 atosoma dominant woody 60-70 can lead to vegetative stage cannot control motion no cure, just treatment for symptoms. can be dignost by using previous techniques |
|
|
Fragile X
|
is a triplet also
more than no cure common to get mental retardation from disease region on X chromosome that can break off over time |
