Question 1

A technique that separates a readable pattern of DNA fragments is ______.

Accepted Answer

Gel electrophoresis is a laboratory method used to separate mixtures of DNA, RNA, or proteins according to molecular size. The molecules to be separated are pushed by an electrical field through a gel that contains small pores. The process results in the separation of DNA fragments by size, allowing for analysis of the pattern of fragments.

Question 2

Gene probes can be labeled for detection with reporter molecules such as _____.

Accepted Answer

Gene probes can be labeled with enzymes, fluorescent dyes, or radioisotopes, all of which serve as reporter molecules to facilitate the detection of specific DNA or RNA sequences.

Question 3

Labeled, known, short stretches of DNA used to detect a speciﬁc sequence of nucleotides in a mixture are known as ______.

Accepted Answer

Gene probes are short strands of DNA or RNA that are labeled and used to detect the presence of complementary sequences by hybridization. They are specifically designed to bind to a sequence of interest, allowing for the identification of specific genes or mutations within a sample.

Question 4

Sequences of DNA that are identical when read from the 5' to 3' direction on one strand and the 3' to 5' direction on the other strand are ______.

Accepted Answer

Palindromic sequences in DNA are stretches of nucleotide sequences that read the same forwards and backwards, mirroring each other on opposite strands. This characteristic is not associated with enzymes or proteins like reverse transcriptases, restriction endonucleases, ligases, or DNA polymerases, but rather with the structure of the DNA sequence itself.

Question 5

DNA strands can be clipped crosswise at selected positions by using enzymes called ______.

Accepted Answer

Restriction endonucleases are enzymes that recognize specific sequences of DNA and cut the DNA strand at those sites, which is why they are used for clipping DNA strands crosswise at selected positions.

Question 6

Restriction endonucleases recognize and clip DNA base sequences called ______.

Accepted Answer

Restriction endonucleases recognize and clip DNA at specific sequences known as palindromes, where the sequence of bases reads the same backward and forward on opposite strands.

Question 7

DNA strands can begin to separate at the temperature of ______.

Accepted Answer

DNA strands can begin to separate at high temperatures, typically around 90°C, as the hydrogen bonds between the base pairs start to break.

Question 8

EcoRI and HindIII are ______.

Accepted Answer

EcoRI and HindIII are restriction endonucleases, enzymes that cut DNA at specific recognition sites.

Question 9

The various techniques by which scientists manipulate DNA in the lab are termed ______.

Accepted Answer

Genetic engineering refers to the techniques used by scientists to manipulate DNA in the lab, including altering the genetic material of organisms.

Question 10

Analysis of DNA fragments in gel electrophoresis is based on ______.

Accepted Answer

All of the choices correctly describe aspects of gel electrophoresis. A) Larger fragments move more slowly through the gel matrix, B) DNA's negative charge causes it to move towards the positive pole, C) DNA fragments are stained to be visible, and D) an electric current causes DNA fragments to migrate through the gel.

Question 11

Any use of an organism's biochemical processes to create a product is referred to as ______.

Accepted Answer

Biotechnology involves using living organisms or their processes to make products or solve problems, encompassing a wide range of techniques and applications from genetic engineering to fermentation.

Question 12

DNA fragments can be separated in gel electrophoresis because ______.

Accepted Answer

Phosphate groups in the DNA backbone carry a net negative charge, which allows DNA fragments to migrate towards the positive electrode during gel electrophoresis.

Question 13

Which of the following is not true of ﬂuorescent in situ hybridization (FISH)?

Accepted Answer

Fluorescent in situ hybridization (FISH) does not use electrophoresis to separate DNA. FISH involves using fluorescent probes that bind to specific parts of the chromosome or RNA molecules within the cell, allowing for the visualization of genetic material without the need for electrophoresis.

Question 14

Geneticists can create sequences of DNA from RNA using enzymes called ______.

Accepted Answer

Reverse transcriptases are enzymes that synthesize DNA from RNA templates, a process essential for the reverse transcription of RNA into DNA.

Question 15

Two different nucleic acids can _____ by annealing at their complementary sites.

Accepted Answer

Two different nucleic acids can hybridize by annealing at their complementary sites, which involves the formation of hydrogen bonds between complementary nucleotide bases.

Question 16

Ampliﬁcation of DNA is accomplished by ______.

Accepted Answer

The polymerase chain reaction (PCR) is a technique used to amplify DNA, making millions of copies of a specific DNA sequence.

Question 17

Fluorescent in situ hybridization (FISH) probes are applied to intact cells and observed microscopically for the presence and location of ______ .

Accepted Answer

FISH probes are designed to bind to specific genetic marker sequences within the DNA of intact cells, allowing for the microscopic observation of these sequences' presence and location.

Question 18

DNA polymerases used in PCR ______.

Accepted Answer

DNA polymerases used in PCR, such as Taq polymerase and Vent polymerase, are chosen for their ability to withstand the high temperatures required for denaturation of DNA strands during the PCR cycle. They do not use RNA templates, are not typically labeled with fluorescent dyes for the PCR process itself, and must remain active at high, not very cold, temperatures.

Question 19

In the formation of recombinant DNA, what enzyme is needed to seal the sticky ends of genes into plasmids or chromosomes?

Accepted Answer

DNA ligase is the enzyme responsible for sealing the sticky ends of DNA fragments, such as those of genes and plasmids, during the formation of recombinant DNA. This enzyme facilitates the formation of phosphodiester bonds between adjacent nucleotides, effectively "gluing" the DNA fragments together.

Question 20

The size of DNA is often given in the number of _____ that it contains.

Accepted Answer

The size of DNA is typically measured in the number of base pairs it contains, as DNA is a double-stranded molecule where bases pair up across the two strands.

Quiz 10: Genetic Analysis and Genetic Engineering