How do you determine sex of a fruit fly?
The X/A ratio 1.0 = female
0.5 =male
What will a metafemale fly look like with chromosomes?
> 1 ratio
What is non disjunction?
when homologs don’t dissociate from one another
When does non-disjunction occur?
anaphase 1
What is aneuploidy?
genetic disorder characterized by an abnormal number of chromosomes in a cell
What is a monoploidy?
haploid set of chromosomes in a species
What is an euploidy?
chromosome number that is exactly the multiple of the monoploid number of chromosomes
What is a polyploidy?
a change in the number of copies of an entire set of chromosomes
What is polyploid tissue?
dna replication but no division leading to a polyploid tissue
What is the purpose of polyploidy?
increasing cell volume or metabolism
What is an autopolyploid?
all chromosomes originated from the same organism
What is an allopolyploid?
each set of chromosomes originated from different organisms
What can deletions lead to?
pseudominance
What is pseudodominance?
recessive allele appears after deletion of dominant gene if the genes are haplosufficient
What is a paracentric inversion?
centromere is outside of the inversion
What is a pericentric inversion?
an inversion spanning the centromere
What happens with a paracentric inversion?
2 chromosomes contain deletions-inviable
1 chromosome is inverted
1 chromosome in normal
What happens in pericentric inversion?
2 chromosomes containing duplication-inviable
1 chromosome inverted
1 chromosome is normal
What is a reciprocal translocation?
rejoining of broken ends of two different chromosomes to one another-not in mitosis or meiosis
What is attachment 1 in translocation and what is the result in the gametes?
each gamete contains a non balanced chromosome (one normal and one translocated so they can’t match) so they are all in viable
What is attachment 2 in translocation and what is the result in the gametes?
balanced chromosomes (two have normal and the other two have both translocated) so they are viable
