Exam 13: Observing Patterns in Inherited Traits

Various forms of a single gene at a given locus is called

In poultry, rose comb is controlled by a dominant allele, and its recessive allele controls single comb. (a) Give the genotype and phenotype produced from crossing a pure-breeding rose comb chicken with a pure-breeding single comb chicken. (b) Give the results of the backcross of the F₁ hybrid with both pure-breeding parents.

MATCHING Classification.Answer the following questions using the group of answers below. a.4 b.6 c.8 d.12 e.24 -In a dihybrid cross between a parent that is a double heterozygote (Aa Bb) and a parent that is homozygous recessive for one gene and heterozygous for the other (aa Bb), how many unique phenotypes potentially will be present in their offspring?

In the garden pea, Mendel found that tall (D) green pods (G) and inflated pods (C) were dominant to their alleles, dwarf (d) yellow pods (g) and constricted pods (c).Given the following genotypes, determine the chances of producing the offspring shown. (a) DD Gg Cc * Dd Gg cc $\rightarrow$ DD gg Cc (b) DD Gg Cc* Dd Gg Cc $\rightarrow$ tall green pod, constricted pod (c) Dd Gg Cc * Dd GG cc $\rightarrow$ tall green pod, inflated pod (d) Dd Gg Cc * Dd Gg Cc $\rightarrow$ D__ G__ cc (e) Dd Gg Cc * Dd gg CC $\rightarrow$ D__ G__ C__ (f) Dd gg cc * DD Gg cc F $\rightarrow$ tall green pod, inflated pod (g) Dd Gg Cc * Dd Gg Cc $\rightarrow$ Dd Gg Cc (h) Dd Gg Cc *Dd Gg Cc $\rightarrow$ dd gg cc

In ____, a pair of nonidentical alleles affecting two phenotypes for a given trait are both expressed at the same time in heterozygotes.

Which of the following does not stimulate the production of males in water fleas?

In tomatoes, red (R) is dominant to yellow (r), tall (D) is dominant to dwarf (d), and smooth (H) is dominant to peach or hairy (h). (a) How many different genotypes are there in relationship to these three characteristics? (b) How many different phenotypes are there in relationship to these three characteristics? (c) How many different homozygous pure-breeding forms can be produced?

In the classic argument of 'nature vs.nurture', nature would most correspond with:

There are three alleles controlling the ABO blood types.I^A and I^B are codominant genes so that the combination I^AI^B produces the AB blood type.The third allele, I^O, is recessive to the other two alleles.Indicate which of these parents could produce the given child: Parents Child Yes or No (a) A * AB B (b) A * O A (c) A * B O (d) A * AB O (e) A * AB B (f) B * B O (g) AB * AB A

If 2 spot (S) is dominant to 4 spot (s), give the genotypes for the parents in the following crosses: (a) 2 spot * 2 spot yields 2 spot and 4 spot (b) 2 spot * 4 spot yields only 2 spot (c) 2 spot * 4 spot yields 2 spot and 4 spot (d) 2 spot * 2 spot yields only 2 spot (e) 4 spot *4 spot yields only 4 spot

Unexpected phenotypes can be the result of

In a certain plant, when individuals with blue flowers are crossed with individuals with blue flowers, only blue flowers are produced.Plants with red flowers crossed with plants with red flowers sometimes produce only red flowers, although other times they produce either red or blue flowers.When plants with red flowers are crossed with plants with blue flowers, sometimes only red flowers are produced; other times either red or blue flowers are produced.Which gene is dominant?

In garden peas, one pair of alleles controls the height of the plant, and a second pair of alleles controls flower color.The allele for tall (D) is dominant to the allele for dwarf (d), and the allele for purple (P) is dominant to the allele for white (p).A tall plant with purple flowers crossed with a dwarf plant with white flowers produces 1/2 tall with purple flowers and 1/2 tall with white flowers.What is the genotype of the parents?

MATCHING Classification.Answer the following questions using the group of answers below. a.4 b.6 c.8 d.12 e.24 -In a dihybrid cross between a parent that is a double heterozygote (Aa Bb) and a parent that is homozygous dominant for one gene and heterozygous for the other (AA Bb), how many unique genotypes potentially will be present in their offspring?

__________ refers to an individual's observable traits.

The offspring of a cross between two individuals that breed true for different forms of a trait are __________.

Congenital deafness in humans is due to the homozygous condition of either of the recessive genes d or e, or both of these genes.Both dominant D and E are necessary for normal hearing.Gene D/d affects the middle ear, while gene E/e affects the inner ear.It does not matter how good the normal inner ear (as indicated by E__) is; if there is something wrong in the middle ear, the individual is unable to hear.The same applies for the other gene.Give the phenotypic results of the following crosses: (a) Dd EE * Dd EE (b) Dd Ee *Dd Ee (c) dd EE * DD ee (d) Dd EE *Dd ee (e) Dd EE * DD Ee

The role of environmental factors on gene expression is illustrated by

In horses, there are four alleles at the A locus.Arranged in dominance sequence they are: A (wild), a^b (bay), a^c (brown), a^d (black) If you bred several bay mares whose sires were brown to a brown stallion whose sire was black, what are the genotypes of the parents; what type of offspring would be produced; and in what proportion?

-The F₂ phenotypic ratio of 9:3:4 is a result of a cross involving