AP Bio 6.1 DNA and RNA Structure
34 flashcards covering AP Bio 6.1 DNA and RNA Structure for the AP-BIOLOGY Unit 6 section.
DNA and RNA structure is a fundamental topic in AP Biology, as outlined by the College Board's AP Biology Curriculum Framework. This section focuses on the molecular composition, structural differences, and functional roles of DNA and RNA, including the significance of nucleotide sequences and base pairing. Understanding these concepts is essential for grasping how genetic information is stored and expressed in living organisms.
On practice exams and competency assessments, questions on DNA and RNA structure often involve identifying components of the molecules or explaining how their structures relate to their functions. Common traps include confusing the roles of DNA and RNA, particularly in processes like transcription and translation. Students may also misinterpret diagrams of nucleotide structures. A frequent oversight in the real world is underestimating the impact of mutations in DNA, which can lead to significant changes in protein function and ultimately affect organismal traits.
Terms (34)
- 01
What is the basic structure of DNA?
DNA is composed of two strands that form a double helix, consisting of nucleotides made up of a phosphate group, a sugar (deoxyribose), and a nitrogenous base (adenine, thymine, cytosine, or guanine). (College Board AP CED)
- 02
How do the nitrogenous bases pair in DNA?
In DNA, adenine pairs with thymine (A-T) and cytosine pairs with guanine (C-G) through hydrogen bonds, maintaining the double helix structure. (College Board AP CED)
- 03
What is the role of RNA in protein synthesis?
RNA serves as a messenger carrying instructions from DNA for controlling the synthesis of proteins, primarily through mRNA, tRNA, and rRNA. (College Board AP CED)
- 04
What are the differences between DNA and RNA?
DNA contains deoxyribose sugar, is double-stranded, and uses thymine, while RNA contains ribose sugar, is single-stranded, and uses uracil instead of thymine. (College Board AP CED)
- 05
What is the function of mRNA?
mRNA (messenger RNA) carries genetic information from DNA to the ribosome, where it serves as a template for protein synthesis. (College Board AP CED)
- 06
What is the significance of the 5' and 3' ends of a DNA strand?
The 5' end of a DNA strand has a phosphate group, while the 3' end has a hydroxyl group, indicating the directionality of the DNA molecule, which is crucial for replication and transcription. (College Board AP CED)
- 07
What is the primary function of tRNA?
tRNA (transfer RNA) is responsible for bringing the correct amino acids to the ribosome during protein synthesis, matching its anticodon with the codon on mRNA. (College Board AP CED)
- 08
How does DNA replication occur?
DNA replication occurs through a semi-conservative mechanism where each strand serves as a template for a new complementary strand, resulting in two identical DNA molecules. (College Board AP CED)
- 09
What are the components of a nucleotide?
A nucleotide consists of three components: a phosphate group, a five-carbon sugar (deoxyribose in DNA and ribose in RNA), and a nitrogenous base. (College Board AP CED)
- 10
What is the role of ribosomes in protein synthesis?
Ribosomes are the cellular structures where protein synthesis occurs, facilitating the translation of mRNA into a polypeptide chain. (College Board AP CED)
- 11
What type of bond connects nucleotides in a DNA strand?
Nucleotides in a DNA strand are connected by phosphodiester bonds, which link the phosphate group of one nucleotide to the sugar of the next. (College Board AP CED)
- 12
What is the function of rRNA?
rRNA (ribosomal RNA) is a key component of ribosomes, playing a structural and catalytic role in protein synthesis. (College Board AP CED)
- 13
What is the process of transcription?
Transcription is the process of synthesizing RNA from a DNA template, where RNA polymerase binds to the promoter region of a gene to initiate synthesis. (College Board AP CED)
- 14
What is the significance of complementary base pairing?
Complementary base pairing ensures accurate replication and transcription of genetic information, as specific bases pair together (A-T and C-G) to maintain fidelity. (College Board AP CED)
- 15
What is the role of helicase in DNA replication?
Helicase is an enzyme that unwinds the DNA double helix, separating the two strands to allow for replication to occur. (College Board AP CED)
- 16
How does RNA differ from DNA in terms of structure?
RNA is typically single-stranded and contains ribose sugar, while DNA is double-stranded and contains deoxyribose sugar. (College Board AP CED)
- 17
What is the function of DNA polymerase?
DNA polymerase is the enzyme responsible for synthesizing new DNA strands by adding nucleotides complementary to the template strand during replication. (College Board AP CED)
- 18
What is the role of the promoter in transcription?
The promoter is a specific DNA sequence where RNA polymerase binds to initiate transcription of a gene. (College Board AP CED)
- 19
What is the difference between exons and introns?
Exons are coding sequences in a gene that are expressed, while introns are non-coding sequences that are removed during RNA processing. (College Board AP CED)
- 20
What is the function of spliceosomes?
Spliceosomes are complexes that remove introns from pre-mRNA and join exons together during RNA processing to produce mature mRNA. (College Board AP CED)
- 21
What is the significance of the start codon in translation?
The start codon (AUG) signals the beginning of translation and codes for the amino acid methionine, establishing the reading frame for the ribosome. (College Board AP CED)
- 22
What is the role of the ribosome in translation?
The ribosome facilitates the decoding of mRNA into a polypeptide chain by providing a site for tRNA to bring amino acids corresponding to the mRNA codons. (College Board AP CED)
- 23
How is the genetic code read during translation?
The genetic code is read in sets of three nucleotides (codons) on the mRNA, each specifying a particular amino acid in the growing polypeptide chain. (College Board AP CED)
- 24
What is the role of aminoacyl-tRNA synthetase?
Aminoacyl-tRNA synthetase is an enzyme that attaches the correct amino acid to its corresponding tRNA, ensuring accurate translation. (College Board AP CED)
- 25
What is the purpose of the 5' cap and poly-A tail in mRNA?
The 5' cap and poly-A tail protect mRNA from degradation, assist in ribosome binding, and facilitate the export of mRNA from the nucleus. (College Board AP CED)
- 26
What is the role of transcription factors?
Transcription factors are proteins that bind to specific DNA sequences to regulate the transcription of genes by facilitating or inhibiting RNA polymerase binding. (College Board AP CED)
- 27
What is the function of the terminator sequence in transcription?
The terminator sequence signals the end of transcription, causing RNA polymerase to detach from the DNA and release the newly synthesized RNA molecule. (College Board AP CED)
- 28
What is the significance of the double helix structure of DNA?
The double helix structure of DNA provides stability and protection for the genetic information, allowing for efficient replication and repair processes. (College Board AP CED)
- 29
What is the role of topoisomerase in DNA replication?
Topoisomerase relieves the tension and supercoiling in DNA ahead of the replication fork by making temporary cuts in the DNA strands. (College Board AP CED)
- 30
What is the function of the lagging strand during DNA replication?
The lagging strand is synthesized discontinuously in short segments (Okazaki fragments) away from the replication fork, requiring multiple RNA primers. (College Board AP CED)
- 31
What is the role of the origin of replication?
The origin of replication is the specific location on the DNA where replication begins, allowing the DNA to unwind and separate for copying. (College Board AP CED)
- 32
What is the difference between prokaryotic and eukaryotic DNA replication?
Prokaryotic DNA replication is typically faster and occurs in the cytoplasm, while eukaryotic replication is more complex, occurs in the nucleus, and involves multiple origins of replication. (College Board AP CED)
- 33
What is the role of the 3' untranslated region (3' UTR) in mRNA?
The 3' UTR plays a role in regulating mRNA stability, translation efficiency, and localization within the cell. (College Board AP CED)
- 34
What is the significance of the coding and non-coding regions in DNA?
Coding regions (exons) are translated into proteins, while non-coding regions (introns) may have regulatory functions or be involved in gene expression control. (College Board AP CED)