Cellular Functions and cDNA Synthesis

The video tutorial explains the concept of complementary DNA (cDNA) by discussing the roles of different nucleic acids in organisms. It highlights how genomic DNA, mRNA, and proteins contribute to cellular functions and phenotypes. The tutorial compares gene expression in neurons and liver cells, emphasizing the identical genomic DNA but different mRNA and protein expressions. It concludes with a detailed explanation of constructing a cDNA library, which involves converting mRNA into stable double-stranded DNA for further analysis.

What is the primary role of proteins in cells?

• To provide structural support

• To store genetic information

• To act as functional elements creating phenotypes

• To transport nutrients

Why do brain and liver cells have different functions despite having identical genomic DNA?

• They have different numbers of chromosomes

• They express different mRNAs and proteins

• They have different amounts of DNA

• They are located in different parts of the body

Which gene is likely to be highly expressed in neurons but not in liver cells?

• Ribosomal subunit C

• Liver enzyme B

• Neuropeptide A

• Hemoglobin

What is the main reason for creating a cDNA library?

• To stabilize mRNA for further applications

• To replicate genomic DNA

• To create new proteins

• To increase the amount of mRNA

What enzyme is used to create cDNA from mRNA?

• Reverse transcriptase

• Ligase

• RNA polymerase

• DNA polymerase

What feature of mRNA is utilized to initiate the creation of cDNA?

• The start codon

• The introns

• The poly-A tail

• The 5' cap

How is mRNA removed during the cDNA library construction process?

• By using a centrifuge

• By using ribonuclease

• By using heat or sodium hydroxide

• By using DNA polymerase

What is the purpose of using random hexamers in cDNA synthesis?

• To degrade mRNA

• To prime DNA polymerase

• To stabilize the DNA

• To increase the length of DNA

What is the role of the poly-DT primer in cDNA synthesis?

• To increase the length of DNA

• To stabilize the DNA

• To provide a 3' hydroxyl group

• To degrade mRNA

What is the final product of the cDNA library construction process?

• Double-stranded DNA

• Double-stranded RNA

• Single-stranded DNA

• Single-stranded RNA