Pharmaceutical Biotechnology: Gel Electrophoresis Size and Shape

What effect does the extent of cross-linking in the gel have on protein migration in gel electrophoresis?

Slows down the migration of proteins (correct)
Speeds up the migration of proteins
Does not affect protein migration
Causes proteins to move in random directions

In gel electrophoresis, why do compact globular proteins migrate faster than elongated proteins of comparable molecular weight?

They are repelled by the gel matrix
They experience less resistance in the gel (correct)
They have higher charge density
They are attracted to the gel matrix

What is the main application area of NATIVE-PAGE in gel electrophoresis?

Evaluating charge density of proteins
Analyzing protein subunits
Separating and detecting enzymes (correct)
Determining molecular weights of proteins

In SDS-PAGE gel electrophoresis, what is determined about proteins in a given sample?

Molecular weights (A) Signup and view all the answers

What is the purpose of treating a protein sample with SDS in SDS-PAGE?

To break disulfide bonds (A) Signup and view all the answers

What happens to protein molecules when treated with SDS in gel electrophoresis?

Proteins undergo denaturation (C) Signup and view all the answers

Which of the following is NOT a basis for separating proteins in native-PAGE?

Molecular weight (D) Signup and view all the answers

In SDS-PAGE, what is the primary factor that determines the separation of proteins?

Size (B) Signup and view all the answers

What type of interaction is involved in nucleic acid hybridization?

Non-covalent, sequence-specific interactions (B) Signup and view all the answers

Which of the following combinations of nucleic acids can undergo hybridization?

All of the above (D) Signup and view all the answers

What is the purpose of a probe in blotting techniques?

To detect the molecule of interest (C) Signup and view all the answers

In SDS-PAGE, what happens to the proteins after treatment with SDS and reducing agents?

They are denatured and acquire the same charge, density, and shape (A) Signup and view all the answers

Which blotting technique is used to detect changes in specific DNA sequences?

Southern blot (A) Signup and view all the answers

Which blotting technique was developed by James Alwine, David Kemp, and George Stark in 1977?

Northern blot (C) Signup and view all the answers

What is the purpose of the Northern blot?

To detect the presence of specific RNA sequences (C) Signup and view all the answers

What is the difference in sample preparation between the Northern blot and the Southern blot?

The Northern blot sample must be denatured, while the Southern blot sample is used in its native state (C) Signup and view all the answers

What is the type of hybridization used in the Northern blot?

RNA-DNA hybridization (D) Signup and view all the answers

What is the relationship between transcription and translation?

Transcription is the production of an RNA copy from a DNA strand, and translation is the production of a functional gene product from that RNA (C) Signup and view all the answers

What type of radiation do unstable isotopes emit to reach a stable form?

Alpha rays (B) Signup and view all the answers

What is the most popular radioisotope used in tagging proteins?

125I (C) Signup and view all the answers

What are the colored end products of enzyme-substrate reactions in ELISA known as?

Chromogens (C) Signup and view all the answers

Which enzyme is commonly used as a tag in Western blotting to produce a yellow-orange end product?

Horseradish Peroxidase (HRP) (C) Signup and view all the answers

What are the two most commonly used enzymes as tags or labels in protein detection?

Horseradish Peroxidase (HRP) and Alkaline Phosphatase (AP) (A) Signup and view all the answers

What is the purpose of antibody probes in Western blotting?

To detect target proteins (C) Signup and view all the answers

What is the role of the ribosome in protein synthesis?

It assembles amino acids into proteins based on the mRNA sequence (D) Signup and view all the answers

What is the primary function of transfer RNA (tRNA)?

To carry amino acids to the ribosome for protein synthesis (D) Signup and view all the answers

What is the relationship between a codon and an anticodon?

A codon is a sequence of three nucleotides in DNA, while an anticodon is its complementary sequence in tRNA (B) Signup and view all the answers

What is the central dogma of molecular biology?

It describes the flow of genetic information from DNA to RNA to proteins (D) Signup and view all the answers

What is the first step in the Northern blotting technique?

Isolate total RNA from target tissues (D) Signup and view all the answers

What is the purpose of Northern blotting?

To detect the presence and quantity of a specific RNA transcript (C) Signup and view all the answers