Chapter 21 Flashcards
“A father has two alleles for eye color, but only passes on one of them to his child.” Which of Mendel’s Laws describes this observation?
Law of Segregation
“Pea plants that have round seeds are no more or less likely than other plants to have yellow pods.” Which of Mendel’s Laws describes this observation?
Law of Independent Assortment
You cross two plants with genotypes AaBbCcDd x AaBbCcDd. What is the probability that one random offspring will be AABbCCdd?
0.25 × 0.5 × 0.25 × 0.25 = 0.0078 (or 1/128)
If 5 of 8 babies in a rabbit litter have long ears (against the expected odds), this is an example of ________ _________ error.
Random sampling error
Will you be asked to calculate the sample size needed to guard against random sampling error?
No
Is there math that can tell you how to calculate this?
Yes
A two-trait test cross between a heterozygote (AaBb) and a homozygous recessive (aabb) typically gives what ratio of genotypes and phenotypes?
1:1:1:1
If two genes are on the same chromosome and their inheritance is linked, how would this affect expected offspring ratios?
There would be a higher inheritance rate of certain allele combinations.
In linked inheritance, which allele is on the same chromosome as “A” in the example?
B
Which allele is linked to “b” in the same example?
a
What process allows a heterozygous parent to pass on an “Ab” or “aB” gamete?
Crossing over
Before whole genome sequencing, what did Sir Thomas Hunt Morgan use to determine the genetic distance between two genes?
Recombination frequencies
What map units are used to measure genetic distances?
Centimorgans (cM)
How far apart are the A and B genes in the example above?
26 centimorgans (26%)
If two genes are closer together on a chromosome, would you expect more or fewer offspring with the genotype Aabb?
Fewer
