AP Bio Ch 15 Quiz Trivia

1. Transcription of a part of a DNA molecule with a nucleotide sequence of A-A-A-C-A-A-C-T-T results in a mRNA molecule with the complementary sequence of

G-G-G-A-G-A-A-C-C.

U-U-U-G-U-U-G-A-A.

T-T-T-G-A-A-G-C-C.

C-C-C-A-C-C-T-C-C.

None of the above.

The given DNA nucleotide sequence is A-A-A-C-A-A-C-T-T. To find the complementary sequence of mRNA, we need to replace each nucleotide with its complementary base. A pairs with U, T pairs with A, C pairs with G, and G pairs with C. Therefore, the complementary sequence of mRNA is U-U-U-G-U-U-G-A-A.

Explanation

The given DNA nucleotide sequence is A-A-A-C-A-A-C-T-T. To find the complementary sequence of mRNA, we need to replace each nucleotide with its complementary base. A pairs with U, T pairs with A, C pairs with G, and G pairs with C. Therefore, the complementary sequence of mRNA is U-U-U-G-U-U-G-A-A.

2. Which of the classes of RNA molecules carries the amino acids that are added to the growing polypeptide chain?

Ribosomal RNA

Transfer RNA

Messenger RNA

Primary mRNA transcript

Transfer RNA (tRNA) carries the amino acids that are added to the growing polypeptide chain during protein synthesis. tRNA molecules have specific anticodons that are complementary to the codons on the messenger RNA (mRNA), allowing them to bind to the mRNA and deliver the corresponding amino acid. This process ensures that the correct amino acids are added in the correct order, forming a specific sequence of amino acids that make up the polypeptide chain. Therefore, tRNA is responsible for the accurate translation of the genetic code into proteins.

Explanation

Transfer RNA (tRNA) carries the amino acids that are added to the growing polypeptide chain during protein synthesis. tRNA molecules have specific anticodons that are complementary to the codons on the messenger RNA (mRNA), allowing them to bind to the mRNA and deliver the corresponding amino acid. This process ensures that the correct amino acids are added in the correct order, forming a specific sequence of amino acids that make up the polypeptide chain. Therefore, tRNA is responsible for the accurate translation of the genetic code into proteins.

3. Which of the classes of RNA molecules is linked with proteins in forming the large and small subunits of a cytoplasmic structure?

Ribosomal RNA

Transfer RNA

Messenger RNA

Primary mRNA transcript

Ribosomal RNA (rRNA) is the correct answer because it is the class of RNA molecules that is linked with proteins in forming the large and small subunits of a cytoplasmic structure called the ribosome. The ribosome is responsible for protein synthesis in cells, and rRNA plays a crucial role in this process by providing the structural framework for the ribosome and assisting in the binding of transfer RNA (tRNA) molecules during translation. Messenger RNA (mRNA) carries the genetic information from DNA to the ribosome, while primary mRNA transcript refers to the initial RNA molecule transcribed from DNA before it undergoes processing.

Explanation

Ribosomal RNA (rRNA) is the correct answer because it is the class of RNA molecules that is linked with proteins in forming the large and small subunits of a cytoplasmic structure called the ribosome. The ribosome is responsible for protein synthesis in cells, and rRNA plays a crucial role in this process by providing the structural framework for the ribosome and assisting in the binding of transfer RNA (tRNA) molecules during translation. Messenger RNA (mRNA) carries the genetic information from DNA to the ribosome, while primary mRNA transcript refers to the initial RNA molecule transcribed from DNA before it undergoes processing.

4. Translation is the first step in the production of a protein from the information in DNA.

True

False

Translation is not the first step in the production of a protein from the information in DNA. The first step is transcription, where the DNA sequence is copied into an RNA molecule. After transcription, the RNA molecule is then translated into a protein in a process called translation. Therefore, the given statement is false.

Explanation

Translation is not the first step in the production of a protein from the information in DNA. The first step is transcription, where the DNA sequence is copied into an RNA molecule. After transcription, the RNA molecule is then translated into a protein in a process called translation. Therefore, the given statement is false.

5. Transcription begins at a region of the DNA called the polymerase.

True

False

The given statement is false because transcription actually begins at a region of the DNA called the promoter, not the polymerase. The promoter is a specific sequence of DNA that signals the start of transcription and binds to RNA polymerase, allowing it to initiate the process of transcribing DNA into RNA. Therefore, the correct answer is false.

Explanation

The given statement is false because transcription actually begins at a region of the DNA called the promoter, not the polymerase. The promoter is a specific sequence of DNA that signals the start of transcription and binds to RNA polymerase, allowing it to initiate the process of transcribing DNA into RNA. Therefore, the correct answer is false.

6. Before Watson and Crick described DNA structure, Linus Pauling proposed a possible model with three strands of support running down the middle and the bases extending out the sides. How close was his guess?

He just missed the number of support strands, which was two rather than three.

The support strands ran along the outside rather than down the center.

The bases were paired in the middle rather than sticking out the sides.

All of the above varied from the real model.

Linus Pauling's guess was not close to the actual DNA structure proposed by Watson and Crick. He incorrectly guessed that there were three support strands running down the middle, whereas the actual structure has two support strands running along the outside. Additionally, Pauling's guess had the bases sticking out the sides, whereas they are actually paired in the middle. Therefore, all of the above statements vary from the real model.

Explanation

Linus Pauling's guess was not close to the actual DNA structure proposed by Watson and Crick. He incorrectly guessed that there were three support strands running down the middle, whereas the actual structure has two support strands running along the outside. Additionally, Pauling's guess had the bases sticking out the sides, whereas they are actually paired in the middle. Therefore, all of the above statements vary from the real model.

7. Prior to protein synthesis, the DNA

Attracts tRNAs with appropriate amino acids.

Must first undergo replication

Contains anticodons that must become codons.

Serves as a template for the production of mRNA.

Adheres to ribosomes for protein synthesis.

The correct answer is that DNA serves as a template for the production of mRNA. During protein synthesis, the DNA molecule is transcribed into mRNA, which carries the genetic information from the DNA to the ribosomes. The mRNA molecule is then translated into a protein by the ribosomes, using the information encoded in the DNA template. This process allows the DNA to serve as a blueprint for the production of proteins.

Explanation

The correct answer is that DNA serves as a template for the production of mRNA. During protein synthesis, the DNA molecule is transcribed into mRNA, which carries the genetic information from the DNA to the ribosomes. The mRNA molecule is then translated into a protein by the ribosomes, using the information encoded in the DNA template. This process allows the DNA to serve as a blueprint for the production of proteins.

8. Split genes are those that contain both exons and introns.

True

False

Split genes are a type of gene structure where the coding sequences, known as exons, are interrupted by non-coding sequences called introns. This means that split genes have both exons and introns present in their DNA sequence. Therefore, the statement "Split genes are those that contain both exons and introns" is true.

Explanation

Split genes are a type of gene structure where the coding sequences, known as exons, are interrupted by non-coding sequences called introns. This means that split genes have both exons and introns present in their DNA sequence. Therefore, the statement "Split genes are those that contain both exons and introns" is true.

9. Gene expression only occurs when a protein is produced.

True

False

Gene expression refers to the process by which the information in a gene is used to create a functional product, such as a protein. However, it is not true that gene expression only occurs when a protein is produced. Gene expression can also result in the production of other molecules, such as RNA molecules, which may have regulatory or structural roles in the cell. Additionally, gene expression can occur without the production of any final product, as in the case of non-coding RNA molecules or regulatory sequences that control the expression of other genes. Therefore, the statement is false.

Explanation

Gene expression refers to the process by which the information in a gene is used to create a functional product, such as a protein. However, it is not true that gene expression only occurs when a protein is produced. Gene expression can also result in the production of other molecules, such as RNA molecules, which may have regulatory or structural roles in the cell. Additionally, gene expression can occur without the production of any final product, as in the case of non-coding RNA molecules or regulatory sequences that control the expression of other genes. Therefore, the statement is false.

10. Which of the classes of RNA molecules is found in almost no prokaryotes?

Ribosomal RNA

Transfer RNA

Messenger RNA

Primary mRNA transcript

The primary mRNA transcript is the initial RNA molecule synthesized from DNA during transcription. It undergoes several modifications, including splicing and addition of a 5' cap and a poly-A tail, to form mature mRNA. This process is more complex and regulated in eukaryotes compared to prokaryotes. Therefore, the primary mRNA transcript is found in almost no prokaryotes.

Explanation

The primary mRNA transcript is the initial RNA molecule synthesized from DNA during transcription. It undergoes several modifications, including splicing and addition of a 5' cap and a poly-A tail, to form mature mRNA. This process is more complex and regulated in eukaryotes compared to prokaryotes. Therefore, the primary mRNA transcript is found in almost no prokaryotes.