Tricky Organic questions

Tricky stuff for Organic Chemistry

By Daniel Martin

Transcription, Translation, and Replication

​What happens at each step

Transcription:

• Definition: Transcription is the process of creating RNA from a DNA template. 

• Purpose: This process produces different types of RNA, including messenger RNA (mRNA), which carries the genetic information to the ribosomes for protein synthesis. 

• Mechanism: RNA polymerase, an enzyme, binds to a specific DNA sequence (the promoter) and unwinds the DNA, then uses one strand of DNA as a template to synthesize a complementary RNA strand. 

• Location: Primarily occurs in the nucleus of eukaryotic cells. 

Transcription, Translation, and Replication

​What happens at each step

Translation: 

• Definition: Translation is the process of using RNA to synthesize proteins.

• Purpose: This process converts the genetic code carried by mRNA into a sequence of amino acids, forming a protein.

• Mechanism: Ribosomes, which are complex structures, read the mRNA sequence (codons) and use transfer RNA (tRNA) to bring the appropriate amino acids to the ribosome.

• Location: Primarily occurs in the cytoplasm of eukaryotic cells.

Transcription, Translation, and Replication

​What happens at each step

Replication:

• Definition: Replication is the process of making an identical copy of a DNA molecule. 

• Purpose: This process is essential for cell division, ensuring each new cell receives a complete copy of the genetic material. 

• Mechanism: DNA polymerase, an enzyme, synthesizes new DNA strands using the existing strands as templates, ensuring accuracy through complementary base pairing. 

• Location: Primarily occurs in the nucleus of eukaryotic cells. 

Multiple Choice

During translation:

• an mRNA, that will be used to make a protein, is made from DNA

• a section of DNA is copied into an complimentary base pair sequence

• amino acids are bonded together into a protein

• a section of DNA is copied into an identical base pair sequence

Multiple Choice

Once DNA replication is complete:

• the double strand contains two daughter strands

• each double strand contains one parent and one daughter strand

• one double strand has both parent strands and the other double strand has both daughter strands

• within a double strand are two strands with identical base sequence

Multiple Choice

When a DNA double strand unfolds and each strand becomes a template for new strand to be built,

it is called:

• Transcription

• Translation

• Replication

Multiple Choice

The process to go from DNA to mRNA is _______

• Transcription

• Translation

• Replication

Amino Acids

An amino acid is composed of a central carbon atom bonded to an amino group (NH2), a carboxyl group (COOH), a hydrogen atom, and an R group (side chain). The R group varies between different amino acids, determining their unique properties. 

Elaboration:

• Central Carbon: The central carbon atom, also known as the alpha carbon, is the backbone of the amino acid structure. 

• Amine Group: The amino group (NH2) is a basic functional group, meaning it can accept a proton. 

• Carboxyl Group: The carboxyl group (COOH) is an acidic functional group, meaning it can donate a proton. 

• Hydrogen Atom: A hydrogen atom (H) is always present on the central carbon. 

• R Group (Side Chain): This is the variable group that distinguishes one amino acid from another. The R group can be a hydrogen, a simple atom like a methyl group (-CH3), or a more complex group of atoms. The R group's properties (size, polarity, charge) influence the overall properties of the amino acid, including its role in protein folding and function. 

• Peptide Bonds: Amino acids are linked together through peptide bonds, formed between the carboxyl group of one amino acid and the amino group of the next. 

Multiple Choice

Which diagram has the R-group of the amino acid circled properly?

Nucleosides:

• Consist of a nitrogenous base (purine or pyrimidine) and a five-carbon sugar. 

• Examples include adenosine, guanosine, cytidine, uridine, and deoxythymidine. 

• Serve as precursors for nucleotide synthesis and play roles in signaling. 

• Obtained by chemical or enzymatic decomposition of nucleic acids. 

Nucleotides

• Are nucleosides with one or more phosphate groups added to the sugar. 

• Form the building blocks of nucleic acids (DNA and RNA). 

• Examples include AMP (adenosine monophosphate), GMP (guanosine monophosphate), CMP (cytidine monophosphate), UMP (uridine monophosphate), and dTMP (deoxythymidine monophosphate). 

• Play crucial roles in energy transfer (e.g., ATP) and other cellular processes. 

Match

Match the drawing with the name

Nucleotide

Nucleoside

Codon

• Nucleotide

• Nucleoside

• Codon

Choose the bestname for the following

Match

Match the structure with the name

Maltose

Sucrose

Glucose

Fructose

• Maltose

• Sucrose

• Glucose

• Fructose

Match

Match the structure with the correct name

3-ethylhexane

ethylmethyl ether

2-methylbutane

2-bromoethanol

Ketopentose

• 3-ethylhexane

• ethylmethyl ether

• 2-methylbutane

• 2-bromoethanol

• Ketopentose