A study investigated the vitamin A content and cholesterol content of eggs from a large population of chickens. The variances were calculated as shown in the table below.
Trait
Variance
Vitamin A
Cholesterol
VP
123.5
862.0
VE
96.2
484.6
VA
12.0
192.1
VD
15.3
185.3
a)Calculate broad and narrow sense heritability for the two traits.
b)What do you need to assume to complete part (a.)
c)Which trait if either is likely to respond to selection best in the short term and in
the long term.
A study investigated the vitamin A content and cholesterol content of eggs from a large population of chickens. The variances were calculated as shown in the table below.
| Trait | ||
| Variance | Vitamin A | Cholesterol |
| VP | 123.5 | 862.0 |
| VE | 96.2 | 484.6 |
| VA | 12.0 | 192.1 |
| VD | 15.3 | 185.3 |
a)Calculate broad and narrow sense heritability for the two traits.
b)What do you need to assume to complete part (a.)
c)Which trait if either is likely to respond to selection best in the short term and in
the long term.
Related textbook solutions
Related questions
1. Clover tongue is the ability to roll ones tongue into threedistinct lobes and is probably inherited as a dominant, simpleMendelian trait. In a population 90.25% of individuals can NOT rolltheir tongue into a clover tongue (i.e. they do not possess theclover tongue trait). What is the expected frequency ofheterozygous individuals in this population?
| 0.9500 |
| 0.9025 |
| 0.0950 |
| 0.0025 |
2. Assume that in the F2 of a series of crosses, 1/256 of theoffspring resemble one of the parents. How many gene loci areinvolved in producing these results?
| 8 |
| 6 |
| 4 |
| 3 |
3. Assume that three gene loci are involved in determiningphenotypes of F2 in an additive manner. How many phenotypic classesare expected?
| 9 |
| 8 |
| 7 |
| 6 |
| 4 |
| 2 |
4. The following values were estimated for corolla length in apopulation of honey-suckle. What is the narrow-sense heritabilityfor this trait in the population?
VE = 4.2
VA = 2.6
VD = 0.9
VI = 0.3
5. Toxin levels were measured in milkweed plants from a largecornfield in Iowa and found to have a mean level of 28.2 mg pergram and a variance of 15.3. Seeds were collected from these plantsand germinated in a single, large greenhouse allowing all plants togerminate and grow under identical environmental conditions. Atmaturity, toxin levels were assessed across all of these plants.The mean toxin level was 33.2 mg per gram with a variance of 8.70.What is the estimated broad-sense heritability for this trait inthis cornfield population of milkweed? Remember that H2= broad-sense heritability = VG/VP.
1- The cap protein is necessary activator for normaltranscription of the lac operon. When cAMP is is high, CAP is boundupstream of the promoter, when its low CAP is not bound. What isthe relationship between glucose and cAMP? If lactose is present,but cAMP is high, why would the gene be OFF?
2- a study was conducted to investigate the levels of calciumand growth hormone excerted in chicken dung on a major chickenfarm.The variance (v) were calculated and are shown bellow
| Variance | Calcium | Growth hormone |
| Vp | 321.2 | 95.8 |
| VE | 119.7 | 69.4 |
| VA | 107.4 | 10.1 |
| VD | 94.1 | 16.3 |
a. Calculate the narrow-sense heritbility for both traits(calcium and growth harmone levels)
b. which trait, if any, will most likely respond to artificialselection?
c- A farmer wants to reduce calcium excertion in his chickens.The population average is 10 g/ml . He selects parents that thataverage 5 g/ml. What calcium excertion levels should we expect inthe offspring?
3- When tryptophan levels are high, how is trancription of thetrp gene inhibited? Be as specfic as possible.
