Question 1

Hemophilia is an X-linked recessive trait in humans. If phenotypically normal parents have children without hemophilia, what information could be determined by a pedigree analysis?
A) Neither parent carries the hemophiliac allele.
B) None of their children is a carrier of the hemophilia allele.
C) None of their children could have hemophiliac children.
D) The exact genotypes of the parents or children

Accepted Answer

Pedigree analysis can help determine the possible genotypes of the parents and children, but not the exact genotypes, especially if the trait is recessive and not expressed in the phenotype.

Question 2

-What information can be inferred about Queen Victoria based on a pedigree of the British royal family?
A) She was the first royal family member with hemophilia.
B) All of her children were born with hemophilia.
C) She was the first royal family member with a mutation in a blood-clotting gene.
D) She inherited a mutation in a blood-clotting allele.

Accepted Answer

Queen Victoria was a carrier of the hemophilia gene, which is a mutation in a blood-clotting allele. This mutation was passed on to some of her descendants, indicating she inherited the mutation rather than being the first to have it or all her children being affected.

Question 3

A DNA fingerprint of a suspect doesn't match a DNA fingerprint from a blood sample taken at a crime scene. What can you conclude?
A) The suspect was never at the crime scene.
B) The blood sample was probably degraded or destroyed in some way.
C) There is no DNA in a blood sample.
D) The blood came from a different person, but the suspect may have been there.

Accepted Answer

The fact that the DNA fingerprints don't match means that the blood sample came from a different person. However, this doesn't necessarily mean that the suspect was not at the crime scene. There could be other explanations for why their DNA was not found at the scene, such as wearing gloves or not leaving any biological material behind.

Question 4

When comparing the DNA fingerprints of a parent and child, the parent's DNA fingerprint will have which of the following genetic traits?
A) all of the DNA bands that the child has
B) more than half of the DNA bands that the child has
C) DNA bands that match those in the child's fingerprint and that aren't from the other parent
D) DNA bands that are very close to bands found in the child but do not match precisely

Accepted Answer

When comparing the DNA fingerprints of a parent and child, the parent's DNA fingerprint will have DNA bands that match those in the child's fingerprint and that aren't from the other parent. These are the genetic traits that are passed down from the parent to the child. The other answer choices are not accurate. The parent may not have all of the DNA bands that the child has (A) or more than half of the DNA bands that the child has (B). Additionally, the DNA bands in the parent's fingerprint should match precisely with those in the child's fingerprint (D).

Question 5

-Which member(s) of the Romanov family shared DNA sequences with England's Prince Philip?
A) both the tsar and the tsarina
B) only the tsar
C) only the tsarina
D) neither the tsar nor the tsarina

Accepted Answer

Prince Philip shared DNA sequences with the tsarina, Alexandra Feodorovna, through their mutual relation to Queen Victoria, making them both descendants of the royal houses of Europe.

Question 6

On a pedigree chart, what symbol would represent a son who is affected by a genetic disorder?
A) a shaded circle
B) a clear circle
C) a shaded square
D) a clear square

Accepted Answer

In a pedigree chart, a shaded square represents a male who is affected by a genetic disorder. A shaded circle represents a female who is affected, while clear squares and circles represent unaffected males and females, respectively.

Question 7

For what purpose is the polymerase chain reaction (PCR) used?
A) to analyze a person's fingerprints
B) to separate fragments of DNA
C) to make many copies of a small amount of DNA
D) to cut DNA into many small pieces

Accepted Answer

PCR is used to make many copies of a small amount of DNA. It is commonly used in research and diagnostic labs to amplify particular segments of DNA for analysis. It can also be used in forensic science to analyze DNA evidence from crime scenes.

Question 8

What are the chances that a hemophiliac male and an unaffected female could have a baby that is a hemophiliac male?
A) 0%
B) 25%
C) 50%
D) 75%

Accepted Answer

Hemophilia is a sex-linked recessive disorder carried on the X chromosome. A hemophiliac male (X^hY) and an unaffected female (XX) can only have carrier daughters (X^hX) and unaffected sons (XY), so the chance of having a hemophiliac male child is 0%.

Question 9

What is a family tree that is used to follow human matings that have already occurred?
A) test cross
B) karyotype
C) sex-linked record
D) pedigree

Accepted Answer

A pedigree is a family tree that tracks and records the occurrence and appearance of a particular genetic trait or condition within a family over several generations. It is used to trace the inheritance of specific traits like genetic disorders or physical characteristics.

Question 10

What does the acronym VNTR mean?
A) variable number tandem repeats
B) varied nucleotides to repeat
C) volumes of nucleotide tandem repeats
D) variation of nucleotide terminal repeats

Accepted Answer

VNTR stands for variable number tandem repeats. It refers to a section of DNA where a short sequence of nucleotides is repeated multiple times in a row, and the number of repeats varies between individuals. This variation can be used in genetic analysis, such as in DNA profiling or paternity testing.

Question 11

Polydactyly is a dominant trait. What symbol on a pedigree chart would represent a male who has polydactyly?
A) a half-shaded square
B) a shaded square
C) a half-shaded circle
D) a clear circle

Accepted Answer

In a pedigree chart, a shaded square represents a male with the dominant trait of polydactyly.

Question 12

Queen Elizabeth II of England is a descendant of Edward VII of England, who was the son of Queen Victoria. Edward VII did not have hemophilia. Prince Philip, who is married to Queen Elizabeth II, is a descendant of Alice, the daughter of Queen Victoria. Alice was a carrier of hemophilia. However, Prince Philip does not have hemophilia. What can you infer about the children of Queen Elizabeth II and Prince Philip?
A) None of the children could have the hemophilia allele.
B) Only the sons could have the hemophilia allele.
C) Only their daughter could have the hemophilia allele.
D) Any one of the children could have the hemophilia allele.

Accepted Answer

The answer of Queen Elizabeth II of England is a...

Question 13

Why do different people have different DNA fingerprints?
A) They have completely different kinds of VNTRs.
B) They have different numbers of the same VNTR.
C) PCR generates some sequences more than other sequences.
D) Restriction enzymes may not cut some VNTRs next to specific DNA sequences.

Accepted Answer

The DNA fingerprint of an individual is made up of variable number tandem repeats (VNTRs), which are repeated sequences of DNA. Different individuals may have the same VNTR sequences, but they will have different numbers of those sequences. This results in unique DNA fingerprints for each individual. Therefore, choice B is correct. Choice A is incorrect because VNTRs are the same types of sequences in all individuals, but they differ in their number. Choice C is incorrect because PCR amplifies all VNTR sequences equally. Choice D is incorrect because restriction enzymes cut VNTRs based on a specific recognition sequence, and this is the same in all individuals.

Question 14

Which item is used to produce genetic fingerprints of people?
A) RNA polymerase
B) Punnett squares
C) pedigree analysis
D) VNTRs

Accepted Answer

VNTRs (Variable Number Tandem Repeats) are used to produce genetic fingerprints of people by amplifying these repeating sequences, which can be used to distinguish individuals. RNA polymerase is an enzyme involved in RNA synthesis, Punnett squares are used to predict the probability of specific offspring from a genetic cross, and pedigree analysis is used to study inheritance patterns in families.

Question 15

Why must DNA fragments be denatured during the polymerase chain reaction?
A) Taq polymerase breaks down when heated.
B) The repeated gene sequences are not present in double-stranded DNA.
C) The primer must bind to a single-stranded template to synthesize double-stranded DNA.
D) VNTRs have DNA sequences that vary in number.

Accepted Answer

During the polymerase chain reaction, the DNA fragments must be denatured or separated into single strands so that the primer can bind to a single-stranded template and synthesize double-stranded DNA. Taq polymerase is heat-stable, so option A is not correct. Option B is incorrect because repeated gene sequences are commonly found in double-stranded DNA. Option D is also incorrect because VNTRs (variable number tandem repeats) are regions of DNA where the number of repeats varies, but this does not relate to the denaturation of the DNA fragments during PCR.

Question 16

What does a half-shaded circle represent on a pedigree chart?
A) a female carrier
B) a female who does not have an allele for the genetic disorder represented
C) a male who is affected by the genetic disorder represented
D) a male carrier

Accepted Answer

A half-shaded circle on a pedigree chart represents a female carrier of a genetic disorder.

Question 17

Because the bones thought to belong to the Romanov family were highly decayed, what type of analysis was used by scientists to determine the gender of each deceased individual?
A) pelvic bone analysis only
B) DNA analysis of material that is specific to the Y chromosome
C) DNA analysis of material that is specific to the X chromosome
D) both pelvic bone analysis and DNA analysis

Accepted Answer

DNA analysis of material that is specific to the Y chromosome is used to determine the gender, as the presence of the Y chromosome indicates a male individual.

Question 18

What are VNTRs?
A) fragments of DNA that have been denatured
B) nucleotide sequences that correspond to specific genes
C) distinct nucleotide sequences that everyone has in different numbers
D) nucleotide sequences that are different in different individuals

Accepted Answer

VNTRs (variable number tandem repeats) are distinct nucleotide sequences that are different in length in different individuals. Everyone has these sequences, but the number of repeats can vary. This makes VNTRs useful for DNA fingerprinting and forensic analysis.

Question 19

Which type of forensic evidence was available for scientists studying the case of the Romanovs?
A) fingerprint
B) toxicology
C) DNA
D) footprint

Accepted Answer

DNA testing was crucial in identifying the remains of the Romanov family, as well as determining their relationships to each other.

Question 20

What is the function of Taq polymerase?
A) to denature DNA so its strands separate
B) to bond to complementary DNA
C) to free nucleotides from a DNA strand
D) to use primers to initiate DNA synthesis

Accepted Answer

Taq polymerase is a DNA polymerase enzyme used in polymerase chain reaction (PCR) to copy DNA. It uses primers to initiate DNA synthesis, so the correct answer is D.

Quiz 8: DNA Detective: Complex Patterns of Inheritance and Dna Profiling

Hemophilia is an X-linked recessive trait in humans. If phenotypically normal parents have children without hemophilia, what information could be determined by a pedigree analysis?

-What information can be inferred about Queen Victoria based on a pedigree of the British royal family?

A DNA fingerprint of a suspect doesn't match a DNA fingerprint from a blood sample taken at a crime scene. What can you conclude?

When comparing the DNA fingerprints of a parent and child, the parent's DNA fingerprint will have which of the following genetic traits?

-Which member(s) of the Romanov family shared DNA sequences with England's Prince Philip?

On a pedigree chart, what symbol would represent a son who is affected by a genetic disorder?

For what purpose is the polymerase chain reaction (PCR) used?

What are the chances that a hemophiliac male and an unaffected female could have a baby that is a hemophiliac male?

What is a family tree that is used to follow human matings that have already occurred?

What does the acronym VNTR mean?

Polydactyly is a dominant trait. What symbol on a pedigree chart would represent a male who has polydactyly?

Why do different people have different DNA fingerprints?

Which item is used to produce genetic fingerprints of people?

Why must DNA fragments be denatured during the polymerase chain reaction?

What does a half-shaded circle represent on a pedigree chart?

Because the bones thought to belong to the Romanov family were highly decayed, what type of analysis was used by scientists to determine the gender of each deceased individual?

What are VNTRs?

Which type of forensic evidence was available for scientists studying the case of the Romanovs?

What is the function of Taq polymerase?