Heritability Practice Problems

For various traits, concordance values have been identified in human monozygotic (MZ) and dizygotic (DZ) twin pairs of the same sex raised together. What do these values indicate regarding the traits?

Horse breeders measured variance values for their herd in height, speed, and endurance. Determine the broad sense heritability (H²) and the narrow sense heritability (h²) for each trait respectively.

Which of the following statements is true regarding the heritability of human height, given that genetic variance accounts for a substantial proportion of the phenotypic variation observed in height, and that the degree of genetic influence on height can vary across different populations and environments?

In a population of birds, the average beak size is 2 cm. A scientist selects the 10% largest beaks for breeding, which have an average beak size of 3 cm. What is the selection differential (S) for beak size?

The difference between the mean phenotype of a selected group of individuals and the mean phenotype of the entire population is termed:

All of the following factors can influence the heritability of a trait, EXCEPT:

Heritability estimates are statistical measures that quantify the extent to which genetic differences contribute to the variation of a trait in a particular population. Heritability estimates range from:

If a population has a trait variance of 0, what can we conclude about the variation in the trait within the population?

The idea that certain alleles can drive the phenotype toward the "affected" end of the continuous distribution is expressed by the term:

Suppose an individual has congenital hip dysplasia in which there is a misalignment in the upper leg bone ball with its socket on the hip. Considering that this phenotype is a threshold trait, who among the following is to be likely affected by this trait?

Sickle cell disease is an example of a disease that is heritable. When the phenotypic variation is caused by genetic variation and too little is contributed by environmental variation, the heritability is considered to be:

Suppose a phenotypic variation is significantly influenced by genetic variation, which of the following is therefore true about concordance among the monozygotic and dizygotic twins?

Which of the following assertions is true if the phenotypic variation is entirely due to nongenetic factors?

In the case of identical twins, if one has asthma and the other does not have the illness, which of the following is therefore true?

Suppose schizophrenia is entirely caused by genetics. What would be the concordance rate among identical twins?

Identify the most accurate statement about a trait that has a heritability of 0.7.

A broad-sense of heritability close to zero indicates that:

In a population of gentoypically identical tomato plants, the variance for weight is 5.24. Determine the broad-sense heritability.

A fisherman decided to increase the growth rate of fish in his pond. He chose the longest fish by 6 weeks for breeding, which was 20 cm. The mean length of the fish population in his pond was 15 cm and the narrow-sense heritability for the length of this fish population was found to be 0.5. Determine the mean length of the fish population in the next generation.

In a herd of dairy cows, the phenotypic variance for muscle growth and fertility is 50 and 26, respectively, and the additive variance for muscle growth and fertility is 8.2 and 5.2, respectively. Which of the following traits will respond best to selection by a farmer?

The narrow-sense heritability of egg yolk and egg white in the eggs of a poultry farm is 0.45 and 0.95, respectively. Identify what you will calculate to investigate whether there is a relationship between these two.

A fisherman decided to increase the growth rate of fish in his pond. He chose the longest fish by 6 weeks, which was 20 cm. The mean length of the fish population in his pond was 12 cm. The mean length of the fish population in the next generation was 15 cm. Determine the narrow-sense heritability for the length of this fish population.

Which of the following techniques can be used to study the genetics of human height?

If the broad-sense heritability of tail length in rats, H² is 0.5 and the phenotypic variance (V_P) is 1.4, What is the genetic variance (V_G) for tail length in these rats?

What is the narrow-sense heritability of tail length in rabbits if the additive genetic variance (V_A) = 0.6, and the phenotypic variance (V_P) = 1.2?

To identify the realized heritability, which equation is utilized by evolutionary biologists?

If the broad-sense heritability (H²) is 0.1, which of the following conclusions is true?

Which of the following selection process is preferred for traits with high heritability on one's records?

What does a 0.75 heritability value imply?

The ratio of additive genetic variance to total phenotypic variance is the narrow-sense heritability. It is calculated using which of the following formulas?

Which of these assertions regarding heritability is TRUE? 

What is narrow-sense heritability (h²)?

What types of quantitative traits have the highest heritability values?

The percentage of a trait determined by genetics is referred to as:

What is true about heritability among the following statements?

The ____ twins are derived from a single zygote while the ____ twins came from two separate fertilization events.

In monozygotic twins, what could have contributed to their phenotypic variance?