Chapter 10 part 2 Flashcards
When a chromosome breaks, both DNA strands are severed at a location called a _______
chromosome break point
Detachment of all or part of one chromosome arm can lead to a _______; the broken fragment contains a telomere and some genetic material
terminal deletion
If any broken chromosome fragment is _______, it will likely be lost during cell division as it can’t attach to the spindle apparatus
acentric
_______ is an example of chromosome deletion and is caused by the loss of 5p15.2-5p15.3
cri-du-chat syndrome
_______ is the loss of an internal portion of a chromosome and results from 2 chromosome breaks
interstitial deletion
_______ is a series of conditions caused by interstitial deletion of multiple genes on chromosome 11
WAGR syndrome
an organism with one normal and one duplication homolog is a _______
partial duplication heterozygote
Unequal crossover does not occur often and most commonly occurs when repetitive regions such as _______ and _______ of homologs misalign
PMSA
PMSB
Large deletions and duplications are identified by a _______, which is the part of one homolog missing on the pairing partner
unpaired loop
Micro-deletions and micro-duplications can be identified by _______
FISH
Sometimes chromosome breakage leads to attachment of the wrong broken ends leading to _______ on the same chromosome or _______ to a nonhomologous chromosome
chromosome inversion
chromosome translocation
_______ when the centromere is outside of the inverted region
paracentric inversion
_______ when the centromere is within the inverted region
pericentric inversion
_______ have one normal and one inverted homolog
inversion heterozygotes
Crossing over within a paracentric inversion results in _______ and ______
dicentric chromosome
acentric chromosome
Crossing over within a pericentric inversion results in both duplicated and deleted regions in _______ of the recombinant products
both
Both paracentric and pericentric inversions result in _______ and _______
2 viable chromosomes
2 nonvialble chromosomes
What are the 3 different types of translocations?
1) unbalanced (one way transfer)
2) reciprocal balanced (two way transfer)
3) Robertsonian (fusion)
In reciprocal balanced translocations, _______ structure is formed at metaphase I of meiosis.
cross-like
Translocation heterozygotes are _______ because only half of alternate segregation leads to normal gametes
semi-sterile
If 2 pairs of chromosomes fuse by Robertsonian translocation, the number of chromosomes drops _______
2n-2
One type of robertsonian translocation between chromosome 21 and 14 is reponsible for _______
familial down syndrome
The DNA and associated proteins of a chromosome are called _______
chromatin
1/2 DNA and 1/2 protein
_______ are small basic proteins that tightly bind DNA
histone proteins
