Inheritance test 5

In a monohybrid cross between two disparate homozygotes, the F1 generation offspring will be heterozygous and display only the dominant trait.

Therefore, there will be a 0% representation of the recessive parent's phenotype in the F1 generation.

This is because the offspring (Rr) are heterozygous and do not express the recessive trait (rr) of the recessive parent. Hence, the correct answer is D, "0%".

Color blindness is an autosomal/x-linked recessive disorder.

For an individual to be affected, they must receive the recessive alleles from both parents.

Thus, the correct answer is B, "Recessive alleles from both parents".

In a monohybrid cross between two different homozygotes, the genotype of the F1 generation is heterozygous dominant.

As a result, they are similar in phenotype, but not in genotype, to the parents.

This makes the correct answer D, "0%".

A gene having more than two alleles is referred to as multiple alleles.

The ABO blood group is a classic example of this, as it has three alleles (I^A, I^B, and i).

So, the correct answer is A, "Multiple alleles".

Red blood cells undergo a development process where they lose their cell nucleus when they mature.

Erythroblasts are immature red blood cells that still contain a cell nucleus.

On the other hand, mature red blood cells, known as erythrocytes, lack a nucleus.

Therefore, the correct answer is A, "Erythroblast".

In Mendelian genetics, a monohybrid cross between heterozygotes (Rr x Rr) will result in an F2 generation with a genotypic ratio of 1:2:1.

This ratio signifies one homozygous dominant (RR), two heterozygotes (Rr), and one homozygous recessive (rr).

So, the correct answer is B, "1:2:1".

In Mendelian genetics, traits are determined by dominant and recessive alleles.

In a dihybrid cross, if all alleles of a seed are recessive (for instance, "rryy"), the phenotypic traits expressed will also be those associated with the recessive alleles.

In this case, "rr" corresponds to "wrinkled" and "yy" to "green", yielding a "wrinkled green" seed.

Mendel's pioneering work on plant genetics did not receive immediate recognition.

The prevalent Darwinian theory and limited understanding of statistics were significant factors in this.

Additionally, the general acceptance of his work was lacking during his time.

Therefore, the correct answer is D, "All of the above".

Epistasis refers to the interaction between genes where one gene masks the expression of another.

The gene that masks the expression of another is called the epistatic gene.

The gene whose expression is masked is referred to as the hypostatic gene.

Hence, the correct answer is B, "Hypostatic".

Blood group compatibility for transfusions is determined by the presence or absence of specific antigens and antibodies.

Donors are determined by the absence of antigens so that the recipient's immune system doesn't react against the donated blood.

Blood group O lacks these antigens, making it a universal donor.

Therefore, the correct answer is A, "It lacks antigens".

Color blindness is a sex-linked trait, carried on the X chromosome.

A color-blind male (XcY) marrying a carrier female (XCXc) can produce offspring with a 50% chance of being color blind.

This is due to the 1:1 ratio of XcXc (color blind) to XCXc (carrier) female offspring and XCY (normal) to XcY (color blind) male offspring.

Hence, the correct answer is C, "50%".

Color blindness is a sex-linked recessive trait located on the X chromosome.

If the mother is color blind (XcXc), she will pass on the color blind X chromosome (Xc) to all her sons.

If the father is not color blind, he will pass on his normal Y chromosome to his sons, making all sons color blind (XcY).

Hence, the correct answer is C, "All sons must be color blind".

A dihybrid cross involves two traits and the parents are heterozygous for both (RrYy x RrYy).

Upon self-fertilization, the phenotypic ratio observed in the F2 generation for two dominant traits (Round Yellow, in this case) is 9:3:3:1.

This means that 9 out of 16 (or 9/16) of the offspring will exhibit both dominant traits.

Therefore, the answer is A, "9/16".

X-linked disorders are carried on the X chromosome.

A father will pass only his Y chromosome to his son, not his X chromosome.

As such, a father cannot pass an X-linked disorder to his son.

Thus, the answer is D, "0%".

Blood group is determined by the presence or absence of specific antigens, which are governed by three alleles: A, B, and i.

The alleles A and B are dominant, while i is recessive.

An individual with two i alleles (ii) will have the blood group O due to the absence of A or B antigens.

Thus, the answer is D, "O".

Genetic distances are understood in terms of recombinant frequencies.

The sum of distances A-B and B-C seems to be 18.5 centiMorgans, but it could be less due to double crossovers not being accounted for.

Hence, the actual distance between genes A and C is likely less than 18.5 centiMorgans.

Therefore, the answer is D, "Less than 18.5%".

The law of segregation, one of Mendel's principles, postulates that during the formation of gametes, the two alleles of each gene separate, and each gamete receives one of these alleles.

Somatic cells are diploid (2n), containing a pair of each chromosome and thus a pair of each gene's alleles.

During meiosis, each gamete becomes haploid (n), meaning it carries only a single set of chromosomes and thus a single allele of each gene.

Therefore, the answer is C, "A single allele".

In birds, unlike in mammals, the females (ZW) are the heterogametic sex, and the males (ZZ) are the homogametic sex.

This means that in avian species, it is the female that determines the sex of the offspring, contrary to mammals where the male determines the sex.

Thus, the correct answer is C, "xy female".

In Drosophila, the sex of an individual is determined by the ratio of X chromosomes to autosomes.

An individual with a genotype XXY would have two X chromosomes (like a typical female) and one set of autosomes, thus the sex would manifest as female.

In humans, an XXY individual would have Klinefelter syndrome and be male, but in Drosophila, this genotype results in a fertile female.

Therefore, the answer is B, "Fertile female".

Genetic disorders can be inherited from parents to offspring through different patterns of inheritance, including autosomal and sex-linked.

Mothers only pass on their X chromosomes to their children, both male (XY) and female (XX).

Consequently, X-linked disorders, which are conditions associated with genes on the X chromosome, can be transmitted from a mother to both male and female progeny.

Therefore, the correct answer is A, "X-linked disorders".

Gene interactions refer to the situations where several genes influence a particular trait.

Epistasis is a type of gene interaction in which one gene interferes with the expression of another.

Non-allelic refers to genes that are not alleles, in other words, they are found at different loci. Non-allelic interaction, therefore, refers to interaction between such genes.

Both terms, therefore, refer to interactions between different genes and can be used interchangeably.

The human ABO blood group system is determined by three alleles; IA, IB, and i, with IA and IB being co-dominant, and i being recessive.

If someone has the O phenotype due to a recessive H gene, their I gene could be any of IAIA, IBIB, IAIB, or ii.

Therefore, the answer is E, "Any of these".

In a Mendelian dihybrid cross, the F1 generation seeds typically express the dominant traits of both genes.

Round and yellow are both dominant traits, so the phenotype of the seeds will be round and yellow, making the correct answer A.

Heredity and variation are fundamental concepts in biology, and the study of these concepts is referred to as genetics.

Thus, the correct answer is D, "Genetics".

A person who is homozygous recessive for the i gene will have the O blood group, and if they are also homozygous recessive for the d gene, their blood type will be Rh negative.

Therefore, a person homozygous recessive for both the i and d genes will have the O negative blood group. Thus, the correct answer is C, "O negative".

Color blindness is an X-linked recessive trait. A daughter who is colorblind (XCXC) must have received an X chromosome with the colorblind trait from both parents.

So, the father must be colorblind, and the mother could either be colorblind too (XCXC) or just a carrier (XCX).

Therefore, both options A and B are possible, making D the correct answer.

In Mendelian inheritance, the interaction between alleles of the same gene is referred to as inter allelic interaction.

Inter genic interaction involves the interaction between alleles of different genes.

Therefore, the correct answer is A, "Inter allelic".

Inheritance patterns where multiple genes influence a single phenotypic trait are known as polygenic inheritance.

This differs from situations where a single gene controls multiple phenotypes (multiple alleles) or where a single gene controls a single phenotype (mono genic).

Therefore, the correct answer is B, "Polygenic".

Blood group is determined by the presence or absence of specific antigens, which are governed by three alleles: A, B, and i.

The alleles A and B are dominant, while i is recessive.

An individual with two i alleles (ii) will have the blood group O due to the absence of A or B antigens.

Thus, the answer is D, "O".

Genetic distances are understood in terms of recombinant frequencies.

The sum of distances A-B and B-C seems to be 18.5 centiMorgans, but it could be less due to double crossovers not being accounted for.

Hence, the actual distance between genes A and C is likely less than 18.5 centiMorgans.

Therefore, the answer is D, "Less than 18.5%".

The law of segregation, one of Mendel's principles, postulates that during the formation of gametes, the two alleles of each gene separate, and each gamete receives one of these alleles.

Somatic cells are diploid (2n), containing a pair of each chromosome and thus a pair of each gene's alleles.

During meiosis, each gamete becomes haploid (n), meaning it carries only a single set of chromosomes and thus a single allele of each gene.

Therefore, the answer is C, "A single allele".

In birds, unlike in mammals, the females (ZW) are the heterogametic sex, and the males (ZZ) are the homogametic sex.

This means that in avian species, it is the female that determines the sex of the offspring, contrary to mammals where the male determines the sex.

Thus, the correct answer is C, "xy female".

In Drosophila, the sex of an individual is determined by the ratio of X chromosomes to autosomes.

An individual with a genotype XXY would have two X chromosomes (like a typical female) and one set of autosomes, thus the sex would manifest as female.

In humans, an XXY individual would have Klinefelter syndrome and be male, but in Drosophila, this genotype results in a fertile female.

Therefore, the answer is B, "Fertile female".

Genetic disorders can be inherited from parents to offspring through different patterns of inheritance, including autosomal and sex-linked.

Mothers only pass on their X chromosomes to their children, both male (XY) and female (XX).

Consequently, X-linked disorders, which are conditions associated with genes on the X chromosome, can be transmitted from a mother to both male and female progeny.

Therefore, the correct answer is A, "X-linked disorders".

Gene interactions refer to the situations where several genes influence a particular trait.

Epistasis is a type of gene interaction in which one gene interferes with the expression of another.

Non-allelic refers to genes that are not alleles, in other words, they are found at different loci. Non-allelic interaction, therefore, refers to interaction between such genes.

Both terms, therefore, refer to interactions between different genes and can be used interchangeably.

The human ABO blood group system is determined by three alleles; IA, IB, and i, with IA and IB being co-dominant, and i being recessive.

If someone has the O phenotype due to a recessive H gene, their I gene could be any of IAIA, IBIB, IAIB, or ii.

Therefore, the answer is E, "Any of these".

In a Mendelian dihybrid cross, the F1 generation seeds typically express the dominant traits of both genes.

Round and yellow are both dominant traits, so the phenotype of the seeds will be round and yellow, making the correct answer A.

Heredity and variation are fundamental concepts in biology, and the study of these concepts is referred to as genetics.

Thus, the correct answer is D, "Genetics".

A person who is homozygous recessive for the i gene will have the O blood group, and if they are also homozygous recessive for the d gene, their blood type will be Rh negative.

Therefore, a person homozygous recessive for both the i and d genes will have the O negative blood group. Thus, the correct answer is C, "O negative".

Color blindness is an X-linked recessive trait. A daughter who is colorblind (XCXC) must have received an X chromosome with the colorblind trait from both parents.

So, the father must be colorblind, and the mother could either be colorblind too (XCXC) or just a carrier (XCX).

Therefore, both options A and B are possible, making D the correct answer.

In Mendelian inheritance, the interaction between alleles of the same gene is referred to as inter allelic interaction.

Inter genic interaction involves the interaction between alleles of different genes.

Therefore, the correct answer is A, "Inter allelic".

Inheritance patterns where multiple genes influence a single phenotypic trait are known as polygenic inheritance.

This differs from situations where a single gene controls multiple phenotypes (multiple alleles) or where a single gene controls a single phenotype (mono genic).

Therefore, the correct answer is B, "Polygenic".

If both parents are heterozygous for the A and B blood types, they each carry the IA, IB, and i alleles.

This results in the potential for their offspring to have any of the four primary blood types: A, B, AB, or O.

Hence, all the options listed are indeed possible, leading to E, "All blood types are possible" being the correct answer.

The transmission of specific traits from parents to their offspring is defined as inheritance.

When the offspring's phenotype is identical to the parent's, this phenomenon is referred to as heredity.

Consequently, the correct answer is B, "Heredity".

A monohybrid cross involving two different homozygous parents results in an F1 generation that is entirely heterozygous.

In the F2 generation, the expected phenotypic ratio is 3:1 for the dominant and recessive traits respectively, according to Mendelian genetics.

This ratio translates to 75% of the offspring displaying the dominant phenotype.

Thus, the correct answer is B, "75%".

Gene linkage refers to the phenomenon where genes located on the same chromosome tend to be inherited together.

If the ratio of recombinants is equal to that of the parents, it indicates there is no linkage between the genes.

As such, the genes assort independently during the formation of gametes.

Therefore, the correct answer is C, "Not linked".

A nucleotide, the building block of DNA, consists of three components: a phosphate group, a five-carbon sugar (deoxyribose), and a nitrogenous base.

The nitrogenous bases in DNA are adenine, guanine, cytosine, and thymine.

Uracil is a nitrogenous base, but it is only found in RNA, not in DNA.

Hence, the correct answer is C, "Uracil".

In genetics, dominant alleles are represented by a capital letter and can express themselves whether they are in homozygous or heterozygous condition.

If a dominant allele is part of a pair, it masks the effect of the recessive allele, which is represented by a lower case letter.

A dominant allele does not require two copies to be expressed, unlike the recessive allele.

Therefore, the correct answer is C, "It is only expressed when two copies are present."