BIO 111: Exam Review

The central dogma of molecular bioogy states that ___________

DNA is transcribed into RNA, which is translated into protein

Which of the following types of molecules help to hold the DNA strands apart while they are being repicated?

single-strand DNA binding proteins

Why does a new DNA strand elongate only in the 5’ to 3’ direction during DNA replication?

DNA polymerase can add nucleotides only to the free 3’ end

A low E value after BLASTing means that the two DNA sequences are _______

Similar

Which of the following molecular techniques was used to determine the order of nucleotides in the human genome:

Sanger sequencing

The mitochondria found in your cells and those of a mushroom _______

are homologous

What characteristics of Taq polymerase make it useful in the PCR process?

It is heat stable and can withstand the heating step of PCR

What bonds of two amino acid molecules form a larger polypeptide?

removal of a water molecule

What is the end goal of cytoplasmic incompatibility?

To result in the maximum number of progeny infected with Wolbachia as possible

Anopheles gambiae

Not found in PA, can transmit malaria

Aedes albopictus

Invasive, can transmit Dengue and Zika

Culex pipiens

Native, can transmit West Nile Virus

Should you be concerned about being bitten by a Wolbachia infected mosquito? Why/why not?

You do not need to be concerned about being bitten by a Wolbachia-infected mosquito because the bacterium is harmless to humans and actually lowers the risk of disease transmission

What does topoisomerase do in DNA replication?

It rotates 360° around DNA and relieves the stress caused by replication supercoiling.

Name one similarity and one difference between PCR and DNA replication

Similarity: Both make copies of DNA

Difference: PCR uses heat to separate DNA strands, while DNA replication uses an enzyme called helicase.

What mathematical formula of the number DNA copies after n rounds of PCR cycling?

2n

What happens when DNA polymerase encounters a dideoxynuleotide tri-phosphate?

DNA polymerase stops making DNA because it can't add any more nucleotides.

Why do mitochondria have their own ribosomes, two membranes, and their own small circular DNA (mitochondrial genomes)?

Mitochondria used to be free-living bacteria that were absorbed by an early cell. They have their own ribosomes to make proteins, two membranes for protection, and their own circular DNA with instructions to make some proteins.

During electrophoresis DNA is attracted to the POSITIVE/NEGATIVE electode because of molecules slight POSITIVE/NEGATIVE charge.

Positive; Negative

Where is the cytochrome oxidase 1 gene located inside the insect cells?

In mitochondria

What does a lysis solution do during DNA extraction?

It breaks the membrane

How are the dyes that are bound to ddNTPs detected by the sequencing machine (sequencer)?

Adenine (yellow)

Cytosine (blue)

Guanine (green)

Thymine (red)

What is the purpose of the extension step (50-65C) during PCR?

DNA polymerase adds new nucleotides to the 3′ end of the DNA primer

topoisomerase

it receives the stress

helicase

it unwinds the double helix

binding proteins

it prevents reformation of a hydrogen bond

primase

it creates RNA primer, which is a starting point

What do the Phred scores of an electropherogram indicate?

Phred scores indicate the accuracy and reliability of DNA base calls. Higher Phred scores mean a lower chance of an error.