Question

In: Biology

In watermelons, bitter fruit (B) is dominant to sweet fruit (b), and yellow spots (N) is...

In watermelons, bitter fruit (B) is dominant to sweet fruit (b), and yellow spots (N) is dominant to no spots (n). The two genes assort independently. A homozygous plant with bitter fruit and yellow spots is crossed with a homozygous plant with sweet fruit and no spots. F1 plants are intercrossed to produce the F2 generation:

a. Give proportions of different phenotypes expected in the F2 generation

b. If an F1 plant is backcrossed with the bitter, yellow spotted parent, what phenotypes and proportions are expected among their offspring?

c. If an F1 plant is backcrossed with the sweet, non-spotted parent, what phenotypes and proportions are expected among the offspring?

Expert Solution

Here a homozygous plant with with bitter fruit and yellow spots (BBNN) is crossed with a homozygous plant with sweet fruits and no spots ( bbnn).

BBNN X bbnn

BbNn F1 generation

( Bitter & Yellow)

Intercrossing of F1 generation is as follows: BbNn X BbNn. The cross can be represented in a punnet square as follows.

	BN	Bn	bN	bn
BN	BBNN-Bitter & Yellow	BBNn-Bitter & Yellow	BbNN-Bitter & Yellow	BbNn- Bitter & Yellow
Bn	BBNn-Bitter & Yellow	BBnn-Bitter & No spots	BbNn- Bitter & Yellow	Bbnn-Bitter & No spots
bN	BbNN- Bitter & Yellow	BbNn-Bitter &Yellow	bbNN-Sweet & Yellow	bbNn- Sweet & Yellow
bn	BbNn- Bitter & Yellow	Bbnn-Bitter & No spots	bbNn- Sweet & Yellow	bbnn- Sweet & No spots

The proportion of phenotypes in F2 generation is,

a) 9 Bitter Yellow: 3 Bitter No spots: 3 Sweet Yellow : 1 Sweet No spots.

b) The genotypes of parents in this back cross (crossing of F1 offspring withany of its parent) is BbNn X BBNN

BbNn X BBNN

	BN	Bn	bN	bn
BN	BBNN-Bitter & Yellow	BBNn-Bitter & Yellow	BbNN- Bitter & Yellow	BbNn- Bitter & Yellow

All offsprings are of dominant characters. ie, Bitter and with Yellow Spots.

c) Here the genotypes of parents in this backcross is BbNn X bbnn

	BN	Bn	bN	bn
bn	BbNn- Bitter & Yellow	Bbnn- Bitter & No spots	bbNn- Sweet & Yellow	bbnn- Sweet & No spots

Here all different phenotypes are produced ie.,

1 Bitter Yellow :1 Bitter No spots : 1 Sweet Yellow : 1 Sweet No spots

gladiator answered 2 years ago

In watermelons, bitter fruit (B) is dominant over sweet fruit (b), and yellow spots (S) are...

In watermelons, bitter fruit (B) is dominant over sweet fruit (b), and yellow spots (S) are dominant over no spots (s). The genes for these two characteristics assort independently. A homozygous plant that has bitter fruit and yellow spots is crossed with a homozygous plant that has sweet fruit and no spots. The F1 are crossed to produce the F2. (a) What are the phenotypes with corresponding phenotypic ratios of the F2? (b) If an F1 plant is backcrossed to...

In tomatoes, yellow flowers (Wf) are dominant over white flowers (wf), and yellow fruit (r) are...

In tomatoes, yellow flowers (Wf) are dominant over white flowers (wf), and yellow fruit (r) are recessive to red fruit (R). A cross was made between true-breeding plants with yellow flowers and yellow fruit, and plants with white flowers and red fruit. The F1 generation plants were then crossed to plants with white flowers and yellow fruit. The following results were obtained: 75 white flowers, red fruit 205 white flowers, yellow fruit 216 yellow flowers, red fruit 37 yellow flowers,...

You've discovered a new plant species in which yellow fruit color (Y) is dominant to green fruit color (y), and round fruit shape (R) is dominant to long fruit shape (r).

You've discovered a new plant species in which yellow fruit color (Y) is dominant to green fruit color (y), and round fruit shape (R) is dominant to long fruit shape (r). The genes for fruit color and shape are located on the same chromosome and are 12 m.u. apart. Determine the proportions of progeny of each phenotype produced for this cross. Yr/yR x yr/yr Reset Help 0% 6% 12% 25% 44% 50% 75% 88% 100% 1. yellow, round:25% 2. yellow,...

In cucumbers: Dull fruit (D) is dominant to glossy (d) Orange fruit (R) is dominant to...

In cucumbers: Dull fruit (D) is dominant to glossy (d) Orange fruit (R) is dominant to cream (r) Bitter cotyledons (B) are dominant to nonbitter (b) A cucumber with the genotype ddRrBb was crossed to a cucumber with the genotype DdRrBb using a branch diagram, determine the probability that an offspring from this cross will be dull and cream with nonbitter cotelydons? (Type in as a decimal and round to 6 decimal digits.)

compare the taste receptors for sour and salty with those for bitter, sweet, and umami.

What are similarities and difference among sweet, umami and bitter taste receptors?

The allele P for PTC tasting (a bitter substance) is dominant over the allele p for...

The allele P for PTC tasting (a bitter substance) is dominant over the allele p for nontasting. If 400 students were tested for this ability and 64 were found to be nontasters, a) Calculate the number of heterozygotes in that population b) What is the adaptive advantage of being able to taste bitter substances?

Long wings in fruit flies are dominant to vestigial wings. A long winged fruit fly is...

Long wings in fruit flies are dominant to vestigial wings. A long winged fruit fly is crossed with a vestigial winged fly. What are the genotypes of the parents and offspring if the cross results in 72 long winged and 68 vestigial winged offspring.

In peas, tall (T) is dominant to short (t), yellow (Y) is dominant to green (y)...

In peas, tall (T) is dominant to short (t), yellow (Y) is dominant to green (y) and round (R) is dominant to wrinkled (r). A purebreeding plant with tall, green and wrinkled pea phenotypes is crossed to a purebreeding plant that is short and makes yellow, round peas. When peas from this F1 generation are crossed, what is the probability of obtaining a short plant that makes yellow, wrinkled peas in the F2?

Tall is dominant over short, green seeds is dominant over yellow seeds. Give the result (...

Tall is dominant over short, green seeds is dominant over yellow seeds. Give the result ( GENOTYPES AND PHENOTYPES) from the cross below. p- Homozygous Tall /Green x Homozygous Short/Yellow F1- ? F2- ? **Any monohybrid cross results in A 3:1 Ratio **Any dihybrid cross results in A 9:3:3:1 Ratio