Calculation of Phenotypic and Genotypic Ratios

Q.

How many different kinds of gametes will be produced by a plant having the genotype AABbCC?

1. Four

2. Three

3. Nine

4. Two

Q. (a) A pea plant bearing axial flowers is crossed with a pea plant bearing terminal flowers. The cross is carried out to find the genotype of the pea plant bearing axial flowers. Work out the cross to show the conclusions you arrive at.

(b) State the Mendel's law of inheritance that is universally acceptable. [5]

Q.

Using a Punnett square, work out the distribution of phenotypic features in the first filial (F1) generation after a cross between a homozygous female and a heterozygous male for a single locus.

Q. A tall true breeding garden pea plants is crossed with a dwarf true breeding garden pea plant. When the F1 plants were selfed the resulting genotypes were in the ratio of

1. 3 : 1 :: Tall : Dwarf
2. 1 : 2: 1 :: Tall homozygous : Tall heterozygous : Dwarf
3. 1 : 2: 1 :: Tall homozygous : Dwarf : Tall heterozygous
4. 3 : 1 :: Dwarf : Tall

Q. A male human is heterozygous for autosomal genes A and B and is also hemizygous for hemophilic gene h. What proportion of his sperms will be abX^h?

1. $\frac{1}{32}$
2. $\frac{1}{16}$
3. $\frac{1}{4}$
4. $\frac{1}{8}$

Q.

A pure tall and a pure dwarf plant were crossed to produce offspring. Offspring were self-crossed. Find out the ratio between true breeding tall to true breeding dwarf.

1. 3:1

2. 1:2:1

3. 2:1

4. 1:1

Q. A plant of $F_1$-generation has genotype "AABbCC". On selfing of this plant, what is the phenotypic ratio in $F_2$-generation:

1. 3: 1
2. 1: 1
3. 9 : 3 : 3: 1
4. 27: 9: 9: 9 : 3 : 3 : 3: 1

Q. The fruits of brinjal (eggplant) come in purple, violet and white. A cross between plants with a deep purpled fruit and a white fruit produces the following progeny in the $F_2$ generation: 45 deep purple, 90 violet and 45 white brinjal plants
Following are the genetic basis of fruit colour in the brinjal, except

1. Phenotype of the hybrid is an intermediate between the two homozygous parents
   
2. Heterozygotes are the blend of homozygous phenotypes
3. One allele is completely dominant over another
4. Trait in the heterozygous condition shows a third phenotype, other than parents
   

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

Q.

A garden pea plant(a) produced inflated yellow pods and another plant (b) of same species produced constricted green pods.Identify the dominant trait.

Q. A woman heterozygous for haemophilia marries a haemophilic man. What will be the ratios of carrier daughters, haemophilic daughters, normal sons and haemophilic sons in F${}_1$ generation?

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

Q.

A cross between pure-bred pea plants having yellow round seeds with those having green wrinkled seeds would produce $F_1$ plants with

1. Round yellow seeds

2. round green seeds

3. wrinkled green seeds

4. wrinkled yellow seeds

Q.

In the above cross, what is the ratio between homozygous plants and heterozygous plants of $F_2$ progeny?

1. 3:1

2. 1:2:1

3. 1:1

4. 1:1:2

Q. Which blood group individual is only homozygous?

1. A
2. B
3. O
4. AB

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. Wrinkled seeds
3. Both round and wrinkled seeds
4. Neither round nor wrinkled seeds

Q. A student designed a hybridization experiment in which, the hybrid expresses the products of both the alleles in its phenotype. What will be the phenotypic ratio in $F_2$ generation?

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

Q.

In a breeding experiment, a pea plant producing yellow seeds is crossed with a green-seeded pea plant. All the $F_1$ plants are yellow-seeded. If these $F_1$ plants are crossed with the green-seeded parent plant, the progeny consists of

1. All green seeded plants

2. Yellow seeded and green seeded plants in 1:1 ratio

3. Yellow seeded and green seeded plants in 3:1 ratio

4. All yellow seeded plants

Q. Which among the following plants produced from a dihybrid cross will have homozygous genetic compositions for both the characters?

	YR	Yr	yR	yr
YR	I	V	IX	XIII
Yr	II	VI	X	XIV
yR	III	VII	XI	XV
yr	IV	VIII	XII	XVI

1. I only
2. I, III and V only
3. III, VII and XI only
4. I and XVI only

Q.

A tall violet flowered plant (TTVV) is crossed with a dwarf white flowered plant (ttvv). When the $F_1$ plants are self-pollinated, a total of 1600 $F_2$ plants are produced. How many plants of $F_2$ generation are similar to the original parents in terms of both genotype and phenotype?

1. 900

2. 300

3. 100

4. 200

Q. A woman heterozygous for haemophilia marries a haemophilic man. What will be the ratios of carrier daughters, haemophilic daughters, normal sons and haemophilic sons in F${}_1$ generation?

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

Q. Heterozygous tall and red flowered pea plants are selfed and total 2000 seeds are collected. What is the total number of seeds for both heterozygous traits?

1. 250
2. 500
3. 1250
4. 750

Q.

A dihybrid tall plant with yellow flowers (TtYy) was crossed with a dwarf plant bearing white flowers (ttyy). What percentage of progeny is expected to be homozygous tall bearing yellow flowers?

1. 0%

2. 25%

3. 50%

4. 75%

Q. A diploid male angiospermic plant is crossed with tetraploid female plant. Endosperm of seed will be.

1. Haploid
2. Triploid
3. Pentaploid
4. Tetraploid

Q. The dihybrid test cross ratio is

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

Q. Pure-bred tall pea plants are first crossed with pure-bred dwarf pea plants. The pea plants obtained in the \(\rm F_1\) generation are then cross-bred to produce \(\rm F_2\) generation of pea plants.

\(\bullet\) (b) What is the ratio of tall plants to dwarf plants in \(\rm F_2\) generation?

Q. A human male is heterozygous for autosomal genes 'A' and 'B'. He is also hemizygous for haemophile gene 'h'. What percentage of sperms will carry 'abh' genotype?

1. 12.5%
2. 0. 31%
3. 75%
4. 0%

Q.

Match the following of column I with that of column II (considering the condition of the cross YY X yy till $F_2$ generation).

Column I	Column II
a. Yy in $F_1$	p. 50%
b. Yy in $F_2$	q. 25%
c. Homozygous dominant in $F_2$	r. 100%
d. Varieties with dominant phenotype in $F_2$	s. 75%

1. a - s, b – p, c – q, d – r

2. a - s, b – q, c – p, d – r

3. a - r, b – p, c – q, d – s

4. a - r, b – q, c – p, d – s

Q. In pedigree analysis symbol $⨀$ is used for

1. Carrier for sex linked recessive
2. Death
3. Affected individuals
4. Heterozygous for autosomal recessive

Q. An agricultural scientist crossed pure-breed round and yellow cotyledon pea plant with wrinkled and green cotyledon pea plant. He observed 800 plants that are heterozygous dominant for both characters. Compute the total number of plants obtained in $F_2$generation.

1. 1000
2. 800
3. 1600
4. 3200

Q. In pea plants, yellow seeds are dominant to green. If a heterozygous yellow seeded plant is crossed with a green seeded plant, what ratio of yellow and green seeded plants would you expect in F${}_1$ generation?

1. 50:50
2. 3:1
3. 9:1
4. 1:3