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;
72 Cards in this Set
- Front
- Back
WZ/ZZ |
Females are the heterogametic sex |
|
What is the easiest way to determine if a particular trait of an organims is autosomally inherited or is sex linked? |
perform a reciprocal cross |
|
How is sex determined in Drosophila |
by the ratio of X chromosomes to the number of sets of autosomes |
|
why do genetic mapping experiments become less accurate when the distances between genes become large? |
multiple crossovers are more common |
|
Trans linkage |
Repulsed Ab/aB |
|
Assume that, regarding a particular gene, one scored 80 second division ascospore arrangement (2:2:2:2 or 2:4:2) and 120 first division arrangements (4:4) in Neurospora. What would be the map distance between he gene and centromere? |
observed/total=20 |
|
cytoplasmic inheritance |
... |
|
The number of Barr bodies in a mouse somatic cell is |
one less than the number of X chromosomes in that cell |
|
A plan of genotype C d/C d is crossed to c D/c D and an F1 testcrossed to c d/c d. If the genes are linked and 40 map units apart, the percentage of c d/c d offspring will be |
20% |
|
The Drosophila genes for white eyes (w), tan body 9t0 and vestigial wings (vg) lie at map positions 2, 12, and 42 respectively. The distance, between w and t is 10, t and vg is 30 and w and vg is 40. Out of 1000 progeny, 24 exhibited doube crossovers. What is the degree of interference? |
0.20 |
|
A human with Turner's syndrome would represent |
a monosomic condition 2n-1 |
|
Two practical benefits of polyploidy that have been exploited by breeders are |
the associated bigger cell size and sterility |
|
Triploids |
... |
|
Consider a species with a diploid (2N) number of 40 chromosomes. How many chromosomes would be found in a monoploid body cell? |
20 |
|
If an individual is heterozygous for a reciprocal translocation, we would expect about a |
50% reduction in fertility |
|
Duplication of short segments of DNA are often found in the genomes of organims. These events can be beneficial because |
the creation of gene families through duplications always have a negative effect on phenotypes |
|
XXY mouse |
male |
|
XXY Drosophelia |
female |
|
XO mouse |
female |
|
XO drosophelia |
Male |
|
Autosomal recessive |
... |
|
Autosomal dominant |
...... |
|
X-linked recessive |
..... |
|
X-linked dominant |
... |
|
Y linked |
... |
|
Aneuploids |
organisms with surpluses or deficits of individual chromosomes
Trisomic Monosomic Tetra sonic Nullsomic |
|
The map of a chromosome interval is X 5 Y 10 Z. From the cross Xyz/xYZ x xyz/xyz, how many double crossovers would be expected out of 1000 progeny |
5 |
|
Maternal effect |
Nuclear gene products are stored in the egg and then transmitted to offsprings |
|
dosage competition |
... |
|
Tortoise-shell cats have a patchwork coloration pattern of orange and black spots. This pattern results from |
dosage compensation through X inactivation |
|
In the tetrad analysis, second division segregation patterns (2:4:2 or 2:2:2:2) result from |
single crossovers between a gene and centromere |
|
You observe the progeny of a Drosophelia cross to consist of all red eyed females and white eyed males. What do you infer about the parental phenotypes |
while eyes females and red eyed males |
|
Diploidy |
... |
|
euploidy |
... |
|
monosomic |
... |
|
Reciprocal translocation |
a transfer of genetic material between non-homologous chromosomes |
|
Because of a translocation involving non-homologous chromosomes, a growth gene suddenly finds itself expressed at a much higher rate and the cell becomes cancerous, this activation of the growth gene is because of |
position effects |
|
In a reciprocal translocation heterozygote, what is the pattern of homologous chromosome association during synapsis |
a cross shaped configuration of 4 chromosomes is formed |
|
In humans, XXY individuals are males with klinefelters syndrome. Which could not give rise to a Klienfelter male |
nondisjunction in meiosis II in the father |
|
Why are triploid species rate? |
chromosomes in a triploid cannot segregate equally during meiosis causing sterility |
|
with nondisjunction, which parent leads to the sex chromosome aneuploid XYY |
father |
|
A husband and wife have normal vision, although both of their fathers are red-green color blind, which is inherited as an X-linked recessive condition. What is the probablility that their first child will be normal vision and male? |
0.25 |
|
In a testcross experiments, the frequency of recombination between genes a and d is 0.3; between d and c, 0.2; between c and b, 0.1; between a and c 0/5; and between b and d, 0.3 What is the order of the three genes? |
a-d-c-b |
|
How does the Y chromosome determine maleness in humans |
by containing a gene coding for the TDF, a protein that directs the development of fetal gonads |
|
Cis linkage |
Coupled: AB/ab |
|
Polyploidy |
In which more than two haploid sets of chromosomes are present, is prevalent in plants and rare in animals |
|
Autopolyploidy |
The addition of one or more sets of chromosomes identical to the haploid complement of the same species
Non junction of entire genome in meiosis
Somatic non disjunction of entire genome followed by reproduction
Colchicine
Even numbers=fertile |
|
Allopolyploidy |
The combination of chromosome sets from different species as a consequence of inter specific matings |
|
Reciprocal translocation |
Involves the exchange of segments between two non homologous chromosomes |
|
Absolute linkage |
. |
|
Linkage with recombination |
. |
|
Independent assortmenr |
.. |
|
Translocation |
Movement of chromosomal segment to a new location in the genome. Down syndrome Fragile X |
|
Robersonian translocation |
Produces a new, large submetacentric or meta centric chromosomes |
|
Trisomic |
2N+1 Klienfelters Down syndrome Jimson weed: different phenotypes |
|
Monosomic |
2N-1 Turner syndrome |
|
Tetrasomic |
2N+2 |
|
Nullisimic |
2N-2 |
|
A haploid cell of a grasshopper |
has half the amount of the genetic information as a diploid cell of a grasshopper |
|
The number of genetically distinct gametes that an individual can produce is predicted |
using the formula 2^N, where N equals the number of heterozygous gene pairs |
|
incomplete dominance |
the hybrid shows a new phenotype that is intermediate between the two homozygotes |
|
co-dominance |
both phenotypes are equally expressed in hybrids |
|
pleiotropy |
when more than one phenotype results from a single gene |
|
complemation test |
. |
|
Genetic ratio of a monohybrid cross (without lethal alleles) in the F2 |
1:2:1 |
|
Phenotypic ratio of a monohybrid cross with a recessive lethal allele in the F2 |
2:1 |
|
Phenotypic ratio of a monohybrid testcross |
1:1 |
|
Phenotypic ratio of a monohybrid cross with incomplete dominance in the F2 |
1:2:1 |
|
Phenotypic ratio of a dihybrid cross with dominant epistasis |
12:3:1 |
|
Phenotypic ratio of dihybrid cross with recessive epistasis |
9:3:4 |
|
Phenotypic ratio of a dihybrid testcross |
1:1:1:1 |
|
Phenotypic ratio of a dihybrid cross with double dominant epistasis |
15:1 |