Question 1

James Watson and Francis Crick received the 1953 Nobel Prize for their work on describing the structure of DNA as:

Accepted Answer

James Watson and Francis Crick are renowned for their discovery of the DNA structure as a double helix, which indeed resembles a twisted ladder. This groundbreaking work laid the foundation for modern molecular biology.

Question 2

Humans share common ancestors.Therefore the DNA STR profile of all humans is the same.

Accepted Answer

While humans do share common ancestors, individual DNA STR (Short Tandem Repeats) profiles vary among individuals, making them a key tool in forensic science for identifying individuals.

Question 3

Because DNA is composed of alternating sugar and phosphate molecules, DNA is known as a double helix.

Accepted Answer

DNA is a double helix because it is composed of two strands of nucleotides that are twisted around each other. Each strand is made up of alternating sugar and phosphate molecules, and the two strands are held together by hydrogen bonds between the nitrogenous bases of the nucleotides.

Question 4

mtDNA is used to trace ancestry through the female line.

Accepted Answer

Mitochondrial DNA (mtDNA) is passed from mothers to their offspring, allowing geneticists to trace maternal lineage and ancestry.

Question 5

(GAAT) (GAAT) (GAAT) (GAAT) is an example of:

Accepted Answer

The sequence (GAAT) repeated multiple times is an example of a Short Tandem Repeat (STR), which are repeating sequences of 2-6 base pairs of DNA. STRs are highly variable among individuals and are used in genetic profiling and forensic identification.

Question 6

Most females have one X and one Y (XY) sex chromosome.

Accepted Answer

Most females have two X chromosomes (XX), while males typically have one X and one Y chromosome (XY).

Question 7

Name a method of separating molecules, such as DNA, based on their size.___________________________________.

Accepted Answer

The answer of Name a method of separating molecules, such...

Question 8

The total amount of DNA in a cell, which is contained in the cell's nucleus (nuclear DNA) and mitochondria (mtDNA), is called the human:

Accepted Answer

The human genome includes all the DNA within a cell, encompassing both the DNA in the nucleus (nuclear DNA) and the DNA in mitochondria (mtDNA).

Question 9

Alternate forms of a gene are called:

Accepted Answer

Alleles are the alternate forms of a gene that arise by mutation and are found at the same place on a chromosome.

Question 10

Ninety-five percent of DNA is non-coding.What term describes non-coding DNA that acts as genetic "on-an-off" switches?

Accepted Answer

Introns are portions of DNA within a gene that are not translated into protein. They can contain regulatory elements, such as enhancers or silencers, that act as genetic "on-and-off" switches to control the expression of genes.

Question 11

Which method is used to identify different STR markers?

Accepted Answer

Adding fluorescent dyes to the PCR reaction is a method used to identify different STR (Short Tandem Repeat) markers. This technique allows for the visualization of the STR regions after PCR amplification, facilitating their identification and analysis.

Question 12

What material is used to isolate and cut DNA?____________________________________________.

Accepted Answer

The answer of What material is used to isolate and...

Question 13

The 95 percent of noncoding DNA is involved in:

Accepted Answer

Noncoding DNA, which makes up about 95% of the human genome, does not code for proteins but is involved in regulating when, where, and how genes are activated. This includes roles in the regulation of gene expression, organization of chromosome structure, and the control of cell growth and differentiation.

Question 14

In 1984, Dr.Alec Jeffreys at the University of Leicaster observed that DNA from different individuals contains different polymorphisms.His laboratory developed a technique for isolating and analyzing these variable areas that is known as:

Accepted Answer

Dr. Alec Jeffreys developed the technique known as DNA fingerprinting or DNA profiling, which allows for the identification of individuals based on their unique DNA patterns. This technique has been widely used in forensic science, paternity testing, and genetic research.

Question 15

To calculate the percentage of people who have a particular allele, population studies are conducted to collect data.

Accepted Answer

Population studies are conducted to collect data on the frequency of alleles within a population, which allows researchers to calculate the percentage of people who have a particular allele.

Question 16

Except for identical twins, no two people on earth have the same:

Accepted Answer

Except for identical twins, every individual has a unique DNA sequence that distinguishes them from every other person.

Question 17

Approximately how many base pairs are in the human body?

Accepted Answer

The human genome contains approximately 6 billion base pairs of DNA, with each cell having about 3 billion base pairs distributed among 23 pairs of chromosomes.

Question 18

Which chromosomes have the same shape and contain the same genes?

Accepted Answer

Autosomes are chromosomes that are not sex chromosomes. They have the same shape and contain the same genes in both males and females.

Question 19

DNA in chromosomes is called

Accepted Answer

DNA in chromosomes is referred to as nuclear DNA because it is located within the nucleus of eukaryotic cells.

Question 20

If one person has two alleles that are the same for a specific STR, then that person is considered to have:

Accepted Answer

Homozygous genotypes occur when an individual has two of the same allele, whether dominant or recessive, for a particular gene.

Quiz 7: Dna Profiling