Incomplete Dominance

Q.

Which of the given traits selected by Mendel w.r.t. pea plants, express themselves in both, homozygous as well as heterozygous conditions?

1. Dominant

2. Recessive

3. Both

4. None of the above

   
   

Q.

What is the Expected Phenotypic Ratio of a Cross Between an RrYy and an RRYY Individual?

Q.

Explain the following terms with an example:

• Co-dominance
• Incomplete dominance

Q.

In 4 ‘o’clock plants, the crossing of pure-bred red and white flowered parental stocks produced pink flowered plants. This type of genotypic expression is called

1. Codominance

2. Gene polymorphism

3. Dominance

4. Incomplete dominance

Q.

Is hybrid homozygous or heterozygous?

Q. In a cross between red-flowered (RR) and white-flowered (rr) plants of snapdragon, the $F_1$ plants were all pink-flowered.
What is the genotype of the $F_1$ and the reason for this phenotype?

1. Rr; Incomplete dominance
2. Rr; Co-dominance
3. rr; Multiple alleles
4. rr; Co-dominance

Q.

How do incomplete dominance and codominance increase the number of phenotypes?

Q.

If the $F_1$ hybrid exhibits a new phenotype that appears as a “blend” of the dominant and recessive phenotypes, it is

1. Complete dominance

2. Codominance

3. Recessive dominance

4. Incomplete dominance

Q. What will be the phenotype of the offspring when a pea plant homozygous for round seeds is crossed with a pea plant producing wrinkled seeds?

1. Both round and wrinkled seeds
2. Round seeds
3. Wrinkled seeds
4. Neither round nor wrinkled seeds

Q.

The phenotypic ratio obtained in the $F_2$ generation of a monohybrid cross in dog flower plant is ___.

1. 1:2:1

2. 3:1

3. 1:1

4. 2:1:1

Q. In Red-White flowered cross of Mirabilis jalapa, $F_2$ generation has red, pink and white flowered plants in the ratio of

1. 1 : 0 : 1
2. 2 : 1 : 1
3. 1 : 2 : 1
4. 1 : 1 : 2.

Q.

Paragraph for below question

नीचे दिये गये प्रश्न के लिए अनुच्छेद

A group of students were studying flower colour inheritance in Pisum sativum. They observed a purple-flowered pea plant of unknown ancestry. They allowed it to self pollinate and collected 60 seeds of it. After planting the seeds, they got 42 purple-flowered plant and 18 white-flowered plants.

Based on above paragraph, answer the following question.

छात्रों के एक समूह ने पाइसम सेटाइवम में पुष्प रंग की वंशागति का अध्ययन किया। उन्होंने अज्ञात वंश का एक बैंगनी पुष्प वाला मटर का पादप देखा। उन्होंने इसका स्व-परागण करवाया तथा 60 बीजों को एकत्रित किया। बीजों को बोने के बाद उन्होंने 42 बैंगनी पुष्प वाले पादप तथा 18 सफेद पुष्प वाले पादप प्राप्त किये।

उपरोक्त अनुच्छेद पर आधारित निम्नलिखित प्रश्न का उत्तर दीजिए।

Q. In a cross between heterozygous purple and white flowered pea plant,

प्रश्न - विषमयुग्मजी बैंगनी तथा सफेद पुष्प वाले मटर पादप के बीच होने वाले संकरण में

1. All progenies will produce white flower
   
   सभी संततियाँ सफेद पुष्प उत्पन्न करेंगी
2. All progenies will produce purple flower
   
   सभी संततियाँ बैंगनी पुष्प उत्पन्न करेंगी
3. Equal proportion of purple and white flowered plants will be obtained
   
   बैंगनी तथा सफेद पुष्प वाले पादपों का समान अनुपात प्राप्त होगा
4. Only 25% progeny will have white flowers
   
   केवल 25% संतति में ही सफेद पुष्प होंगे

Q. Phenotypic and genotypic ratio in $F_2$ generation in incomplete dominance is

1. 1 : 2 : 1 and 1 : 2 : 1
2. 3 : 1 and 1 : 2 : 1
3. 9 : 6 and 3 : 1
4. 9 : 3 : 3 : 1 and 1 : 2 : 1 : 4 : 1 : 1 : 2 : 1 : 2 : 1.

Q. A monohybrid cross is conducted between a plant with axial flowers (AA) and a plant with terminal flowers (aa).
Identify the correct statement(s) on the basis of the information given.

Statement 1: Plants with terminal flowers are produced in $F_1$ generation.

Statement 2: Allele responsible for the terminal position of the flower fails to express in presence of the allele responsible for the axial position of flowers.

1. Both the statements are correct
2. Only statement 1 is correct
3. Both the statements are incorrect
4. Only statement 2 is correct

Q.

If in a plant red colour of the flower is dominant over white. A cross was made between a plant containing red flowers and another with white flowers. The cross yields $50\%$ white-flowered plants and $50\%$ red-flowered plants. The genotype of the parent with a red flower is:

1. Homozygous

2. Heterozygous

3. Can not be determine

4. Can be homozygous or heterozygous

Q. What will be the phenotype of the offspring when a pea plant homozygous for round seeds is crossed with a pea plant producing wrinkled seeds?

1. Round seeds
2. Neither round nor wrinkled seeds
3. Wrinkled seeds
4. Both round and wrinkled seeds

Q. The phenotype ratio of a dihybrid cross in which both the genes show incomplete dominance is

1. 1 : 2 : 1
2. 9 : 3 : 3 : 1
3. 1 : 2 : 1 : 2 : 4 : 2 : 1 : 2 : 1
4. 3 : 1

Q. In $Mirabilis$ & $Antirrhinum$ plant, the appearence of the pink hybrid (Rr) between cross of a red (RR) and white (rr) flower parent indicates

1. Incomplete dominance
2. Segregation
3. Dominance
4. Heterosis

Q. In a cross of red and white flowered Snapdragon, $F_1$ plants will have flowers

1. Red
2. White
3. Both A and B
4. Pink

Q.

A cross between two snapdragon varieties - one with red flowers and one with white flowers produces $F_1$ hybrids all with pink flowers . This is an example for

1. Multiple allelism

2. Codominance

3. Complete dominance

4. Incomplete dominance

Q. $F_2$ generation in a Mendelian cross showed that both genotypic and phenotypic ratio are same as 1 : 2 : 1. It represents a case of

1. Monohybrid cross with complete dominance
2. Monohybrid cross with incomplete dominance
3. Co-dominance
4. Dihybrid cross

Q. In snapdragon, when pink flowers are crossed with white flowers then ratio of pink flowers and white flowers in the progeny is

1. Pink red and white in 1 : 2 : 1 ratio
2. 10% Red
3. Pink and white in 1 : 1 ratio
4. Red and white in 3 : 1 ratio

Q. Phenotypic ratio of a monohybrid $F_2$ progeny of incomplete dominance is

1. 1 : 2 : 1
2. 1 : 1 : 1 : 1
3. 3 : 1
4. 2 : 1 : 1

Q. Explain incomplete dominance with example.

Q. In Mirabilis/Antirrhinum, hybrid between red and white flowered plants is pink flowered. This is

1. Heterosis
2. Segregation
3. Dominance.
4. Incomplete dominance

Q. What is incomplete dominance? Give an illustration.

Q.

If the $F_1$ hybrid exhibits a new phenotype that appears as a “blend” of the dominant and recessive phenotypes, it is ___.

1. Codominance

2. Incomplete dominance

3. Complete dominance

4. Recessive dominance

Q.

If the $F_1$ hybrid exhibits a new phenotype that appears as a “blend” of the dominant and recessive phenotypes, it is ___.

1. Complete dominance

2. Incomplete dominance

3. Recessive dominance

4. Codominance

Q.

The phenotypic ratio obtained in the F2 generation of a monohybrid cross in Dog flower plant is

1. 2:1:1

2. 3:1

3. 1:1

4. 1:2:1

Q. Tallness (T-) is dominant over dwarfness (tt) while red flower colour (R-) is dominant over white colour (rr). A plant with genotype TtRr is crossed with plant of genotype ttrr. Percentage of progeny having tall plants with red flowers is

1. 25%
2. 100%
3. 75%
4. 50%