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Right choice is (C) AB

The best I can explain: The person has TWO ALLELES IA and IB. These are codominant alleles. Thus, both of them will produce their products. Hence the person will have the BLOOD group AB.

Right OPTION is (c) codominance

Easy explanation: The cattle coat color is an instance of codominance. Here the coat color of the progeny of PARENTS that have contrasting coat COLORS has PATCHES. Thus, both the alleles EXPRESS codominantly resulting in a new phenotype.

The CORRECT answer is (d) i

Explanation: The I gene codes for THREE antigens: IA, IB, and i. IA and IB code for sugar. The i allele does not code for any sugar.

The correct answer is (b) False

The explanation: The genes IA and IB code for SUGAR. However, these SUGARS are SLIGHTLY different. These differ in few monomers.

Right answer is (a) True

The best I can EXPLAIN: The I gene is responsible for the blood GROUP. In a COMPLEX pathway, the allele present at the locus of I gene DETERMINES the nature of the sugar polymer expressed by the RBCs. Thus INDIRECTLY, it codes for the sugar polymer.

The correct CHOICE is (d) carbohydrates

To explain: The ABO blood group is determined by the ANTIGENS present on the RBCs of a human. These antigens are sugar POLYMERS.

The correct answer is (c) BLOOD grouping in humans

The best explanation: The ABO blood grouping in humans is an INSTANCE of codominance. Here the lack of both A and B alleles PRODUCES a new phenotype: The O blood group.

The correct choice is (C) codominance

For explanation I would say: Codominance REFERS to the production of a new phenotype when both factors that give opposing traits are PRESENT. This is observed in ABO BLOOD grouping in humans.

Correct answer is (d) More efficient enzyme

To elaborate: Recessive ALLELES lose the capability to encode because of the presence of a BETTER functioning allele. HENCE a more efficient enzyme is highly UNLIKELY to be encoded by a recessive GENE.

Right option is (C) CODOMINANCE

For EXPLANATION: Codominance REFERS to the equal likelihood of both alleles expressing. Thus, the progeny resembles both the parents.

Correct choice is (a) Gene

For EXPLANATION: The factors hypothesized by Mendel ENCODE for traits that are expressed. These are now called genes. Genes are fragments of DNA that code for a functional PROTEIN. In eukaryotes, genes are composed of two elements namely, exons and INTRONS. Exons code for an mRNA transcript, while the introns are non-coding elements and are removed out by a spliceosomal complex.

Right OPTION is (b) Heterozygosity

The EXPLANATION is: The blending of characters is the characteristic feature of incomplete dominance. This requires the PRESENCE of TWO factors in the organism. Hence it occurs only in the heterozygous STATE.

The correct answer is (b) Incomplete DOMINANCE

For explanation I would say: Incomplete dominance involves the blending of characters in the PROGENY that are heterozygotes. Here red and white-flowered plants PRODUCE pink-flowered progeny. Hence this is an instance of incomplete dominance.

Correct option is (b) 250 tall plants, 500 intermediate plants, and 250 small plants

To explain I would say: The phenotypic ratio of the progeny that EXHIBITS incomplete dominance is 1:2:1. Therefore, of 1000 plants sampled from the progeny, 250 should be tall, 250 should be small, and 500 intermediate plants if incomplete dominance holds.

The correct ANSWER is (b) False

Explanation: Complete dominance refers to the Mendelian pattern of inheritance. Both incomplete and complete dominance PRODUCE OFFSPRINGS that have the same genotypic ratios. The two processes DIFFER in the phenotypic ratios.

The correct option is (b) False

Easy explanation: The LAW of dominance still holds. INCOMPLETE dominance also involves a pair of factors that encode for a specific phenotype. However, the dominance of one over the other is incomplete, GIVING rise to a blending of phenotypes in heterozygotes.

Correct choice is (B) Flower COLOR in snapdragon

The best explanation: The garden peas exhibit Mendelian inheritance. Human BLOOD grouping shows CODOMINANCE. Snapdragon flower color shows incomplete dominance.

Correct ANSWER is (b) The ALLELES separate during meiosis and PAIR up during fertilization

Best explanation: The second law of Mendel is the law of segregation. It states that the alleles are segregated during the process of meiosis and these pair again after fertilization to restore the genetic composition. This explains the loss of recessive phenotype in F1 and reappearance of it in F2 generation.

The correct OPTION is (b) Law of Dominance

The explanation: According to the law of dominance, the FACTORS occur in pairs. One factor is DOMINANT over the other. This leads to suppression of the expression of the recessive allele. THUS, the recessive allele can express only when both copies of the gene are recessive. This can give the F2 PROGENY the observed phenotype of 75% dominant and 25% recessive.

Correct option is (a) LAW of Recessivity

Explanation: MENDEL stated three laws of INHERITANCE. These are the law of DOMINANCE, the law of segregation, and the law of independent assortment. The law of recessivity is not the law PROPOSED by Mendel.

Correct answer is (b) LAW of Dominance

To explain I WOULD say: The FIRST law of Mendel, also known as the law of dominance, explains the outcome of a monohybrid cross. It explains the reason for all progeny to have dominant phenotype as all progeny CONTAIN one COPY of each allele obtained from parents, one of which is dominant over the other.

The correct option is (c) Law of SEGREGATION

Easiest explanation: The second law of MENDEL is called the law of segregation. It gives the rule or PATTERN FOLLOWED by the GAMETES during meiosis.

The correct option is (b) Law of Dominance

To ELABORATE: The laws of inheritance were proposed by Mendel. These were VERIFIED by his EXPERIMENTS on PEA plants and many others that followed him. The first of these laws is termed as the law of dominance.

Right option is (a) Principles of INHERITANCE

For EXPLANATION I would say: Mendel FORMULATED specific rules that he observed based on his studies in pea plants. These rules were LATER found to be UNIVERSAL and, in fact, the central pillars of genetics. These are now known as the principles or laws of inheritance.

The correct option is (b) False

Best EXPLANATION: Based on his studies of monohybrid crosses, Mendel proposed two laws of INHERITANCE. The third law CAME from his studies of DIHYBRID crosses.

Right choice is (b) Vv

Easiest EXPLANATION: If a cross occurs between violet-flowered and white-flowered plants, the OFFSPRINGS will have an allele V. To have both violet and white flowers, the violet-flowered PARENT should be able to PRODUCE both V and v containing gametes. Thus, the genotype of the unknown parent will be Vv.

The CORRECT choice is (a) Test cross

The best explanation: To determine the genotype of a tall plant amongst the F2 PROGENY, MENDEL employed test crossing. Here he crossed the tall plant with a recessive dwarf plant. If the genotype of the tall plant were TT, the offspring will all be tall. However, if the genotype is Tt, there will be 50% tall and 50% dwarf plants.

The correct choice is (a) VV

Easiest explanation: TEST cross involves a cross between the PLANT whose genotype is to be DETERMINED with the homozygous recessive plants. If a violet-flowered plant is crossed with white-flowered plant, the offsprings will have ONE v allele. Thus, to exhibit a phenotype of violet-flowering, the genotype will be Vv. Hence the parent will have a genotype of VV.

Right choice is (b) Binomial expression

Best EXPLANATION: The binomial expression (ax+by)^2 can be used to model the MENDELIAN genetics of F2 progeny. The x and y refer to the dominant and the RECESSIVE gametes OBTAINED from the F1 heterozygous progeny.

The CORRECT answer is (b) 0% tall and 100% DWARF plants

Easy explanation: The F2 dwarf plants are HOMOZYGOUS recessive. Therefore, the self-crossing will only produce dwarf plants as no copy of the DOMINANT allele is present.

Right choice is (b) F1

The BEST explanation: The genotypic ratio refers to the ratio of different GENOTYPES observed in a population. In the F2 generation of a MENDELIAN cross, the proportion of homozygous dominant: HETEROZYGOUS: homozygous recessive is 1:2:1.

The CORRECT answer is (b) similar; dissimilar

To explain: The law of segregation states that the factors separate during gamete formation. Thus a homozygous parent will PRODUCE gametes that have similar factors while the heterozygous parent WOULD produce gametes with dissimilar ALLELES.

Correct CHOICE is (d) Factors SEGREGATED during the process of meiosis

To EXPLAIN I would say: The PRINCIPLE of DOMINANCE does not state the segregation of factors. This is stated by the law of segregation or separation.

The correct answer is (a) Factors

The BEST explanation: The LAW of dominance states characters ENCODED by discrete units. Mendel called these factors, which he believed transferred from parents during progeny during fertilization. These are now known as GENES.

Correct choice is (c) F2

The explanation: The phenotypic ratio is the ratio of different PHENOTYPES observed in the progeny. In the F2 generation of a MENDELIAN cross, there are 75% plants with dominant PHENOTYPE and 25% plants with a RECESSIVE phenotype. This gives a phenotypic ratio of 3:1.

The CORRECT OPTION is (b) PHENOTYPIC ratio

To explain I would say: The PHENOTYPES of a progeny can be studied by manually counting the offsprings. The ratio of different phenotypes defines the phenotypic ratio of the cross.

Right answer is (a) 250 Homozygous DOMINANT, 500 Heterozygous dominant and 250 Homozygous recessive

Easy explanation: Self-fertilization of HETEROZYGOTE will LEAD to 25% homozygous dominants, 25% homozygous recessive, and 50% heterozygous dominants. This is satisfied if the POPULATION sampled has 250 homozygous dominant and recessive plant and 500 heterozygous dominant plants.

Correct answer is (a) genotypic ratio

To elaborate: The GENOTYPES of a progeny can be STUDIED USING Punnett square. The ratio of different genotypes is CALLED the genotypic ratio.

Correct answer is (a) 50% V and 50% v

Easy explanation: The PROCESS of segregation that occurs during meiosis is a RANDOM process. THUS the GAMETES will have 50% of each allele. Hence Vv HETEROZYGOUS plant would produce 50% V and 50% v containing gametes.

The correct option is (B) False

The best I can explain: The F1 progeny has only AXIAL flowers, which imply that axial trait is DOMINANT over the terminal trait. However, the F1 progeny are heterozygous. UPON self-crossing, 25% of the F2 progeny will be homozygous for the RECESSIVE trait, resulting in the formation of 3:1 ratio of axial flower-bearing to terminal flower-bearing plants.

The correct answer is (a) LEFT column and top row

Easiest explanation: Punnett square gives a graphical representation for the TRANSFER of genetic information in crosses. The gametes from the PARENTS are REPRESENTED on the top and the left SIDES of the Punnett square.

Correct CHOICE is (a) REGINALD Punnett

The EXPLANATION: The Punnett square was discovered by a British SCIENTIST named Reginald Punnett. Its importance was RECOGNIZED by Gregor Mendel, who used it to study the patterns of inheritance and thus formulate the laws of inheritance.

Correct option is (a) Punnett square

The explanation is: The Punnett square is a mathematical tool USED in probability and statistics. Mendel employed it to study the genotypes of F1 and F2 PROGENY BASED on the games produced by the PREVIOUS generation.

Right answer is (c) Stochastic

Easy explanation: SEGREGATION of alleles leads to each gamete having only a SINGLE allele at the end of meiosis. This process is purely random or stochastic. THUS, the PROBABILITY of a gamete having either alleles is 50%.

Correct option is (a) Monohybrid cross

Explanation: The offsprings produced from this cross are heterozygous for only ONE GENE, which ENCODES for tallness. THUS, the cross is called a monohybrid cross.

The correct OPTION is (a) genotypes, PHENOTYPES

The best I can explain: The genotypes REFER to the allelic COMPOSITION of a particular gene. Thus VV, Vv, and vv are the genotypes. Violet and white are the phenotypes. These refer to the expressed trait.