DNA & RNA Vocabulary Flashcard Test I

The correct answer is Oswald Avery. The research group used DNase to destroy DNA and RNase to destroy RNA. Based on their findings, the team leader, Oswald Avery, concluded that DNA is responsible for transformation in bacteria.

Adenine is a purine, which are six-membered rings attached to five membered rings. Purines are a type of organic compound that are composed of a double-ring structure, with a six-membered ring fused to a five-membered ring. Adenine is one of the two purine bases found in DNA and RNA, along with guanine.

Chase and Hershey used the radioactive isotope Phosphorus-32 to label DNA molecules. Radioactive isotopes can be used as tracers to track the movement of molecules. Phosphorus-32 specifically labels DNA because it is incorporated into the backbone of the DNA molecule during DNA synthesis. This allows researchers to study the replication and movement of DNA in experiments, such as the famous Hershey-Chase experiment that confirmed DNA as the genetic material.

Purines are nitrogenous bases that have a double ring of carbon and nitrogen atoms, such as adenine and guanine. These bases are essential components of nucleotides, which are the building blocks of DNA and RNA. Purines play a crucial role in the genetic code as they pair with pyrimidines (another type of nitrogenous base) to form the base pairs that make up the DNA double helix. Adenine always pairs with thymine (in DNA) or uracil (in RNA), while guanine always pairs with cytosine. Therefore, purines are important for maintaining the structure and function of genetic material.

Pyrimidine refers to nitrogenous bases that have a single ring of carbon and nitrogen atoms, including cytosine and thymine. These bases are essential components of nucleotides, which are the building blocks of DNA and RNA. Pyrimidines play a crucial role in genetic coding and protein synthesis.

In 1952, Alfred Hershey and Martha Chase conducted a series of experiments to confirm that DNA is the "genetic material." These experiments involved infecting bacteriophages, which are viruses that infect bacteria, with radioactive markers. The radioactive markers were either attached to the protein coat of the bacteriophage or the DNA inside it. The results of their experiments showed that when the bacteriophages replicated, only the DNA was transferred to the next generation of viruses, confirming that DNA is indeed the genetic material responsible for inheritance.

DNA ligase is a specific type of enzyme that plays a crucial role in DNA replication and repair. It facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond. This bond is essential for connecting the sugar-phosphate backbone of DNA molecules, ensuring the integrity and stability of the DNA structure. DNA ligase is particularly important in sealing the gaps between Okazaki fragments during lagging strand synthesis in DNA replication and in repairing DNA damage, such as DNA breaks or nicks. Therefore, DNA ligase is an essential enzyme in maintaining the integrity of the genetic material.

Streptococcus pneumoniae is a human pathogenic bacterium that has been recognized as a major cause of pneumonia.

Virulence refers to the relative pathogenicity of an organism. It is a measure of the severity or harmfulness of a pathogen in causing disease. The term is used to describe the ability of an organism to invade and damage a host, leading to the development of symptoms and the progression of the disease. A highly virulent organism is more likely to cause severe illness or death, while a less virulent organism may cause milder symptoms or be less likely to cause disease altogether.

Cytosine is one of the four main bases found in DNA and RNA, along with adenine, guanine, and thymine. These bases are the building blocks of nucleic acids and are responsible for the genetic information in living organisms. Cytosine pairs with guanine in DNA and with uracil in RNA through hydrogen bonding. It plays a crucial role in the structure and function of DNA and RNA molecules, allowing for the accurate replication and transmission of genetic information.

Frederick Griffith was a British bacteriologist who specialized in studying the pathology of bacterial pneumonia. He is known for his groundbreaking experiments on the transformation of bacteria, which played a significant role in the discovery of DNA as the genetic material.

A bacteriophage is a type of virus that infects bacteria and takes control over the metabolism of the bacterial host. It injects its genetic material into the bacterium, which then uses the host's cellular machinery to produce more copies of the virus. Eventually, the bacteriophage causes the bacterium to burst, releasing new viral particles to infect other bacteria. Bacteriophages are commonly used in research and biotechnology applications, as they can be manipulated to target specific bacterial species and can potentially be used as alternatives to antibiotics.

DNA replication is the process by which DNA is copied in a cell before mitosis, meiosis, or binary fission. During DNA replication, the double-stranded DNA molecule unwinds and separates into two strands, and each strand serves as a template for the synthesis of a new complementary strand. This process is catalyzed by DNA polymerase, which adds nucleotides to the growing DNA strand based on the template strand. The result is two identical copies of the original DNA molecule, each consisting of one old strand and one newly synthesized strand, which is known as semi-conservative replication.

DNA polymerase is the correct answer because it is an enzyme that is responsible for synthesizing DNA molecules from nucleotide building blocks. This enzyme plays a crucial role in DNA replication, where it adds new nucleotides to the growing DNA strand during the process. RNA polymerase, mRNA polymerase, tRNA polymerase, and rDNA polymerase are incorrect options as they are not involved in synthesizing DNA molecules.

A pathogen is any organism that is capable of causing disease or a toxic response in another organism. Pathogens can be bacteria, viruses, fungi, or parasites that invade the body and disrupt its normal functioning. They can cause a wide range of diseases, from common colds to more severe infections like tuberculosis or malaria. Pathogens have specific mechanisms that allow them to evade the immune system and multiply within the host, leading to the development of symptoms and illness. Understanding pathogens is crucial for the development of effective treatments and preventive measures against infectious diseases.

Escherichia coli is a gram-negative bacteria that is commonly found in the intestinal tract of animals, soil, and water. It is characterized by its rod-shaped morphology, which is why the correct answer is "rod".

Thymine is the correct answer because it is also known as 5-methyluracil, which is a pyrimidine nucleobase. Thymine is one of the four nucleobases found in DNA and pairs with adenine during DNA replication and transcription.

A bacteriophage or virus that immediately begins to subvert the host machinery and multiply is called virulent.

Frederick Griffith discovered that a harmless strain of Streptococcus pneumoniae could be made virulent after being exposed to heat-killed virulent strains. This suggests that there is a substance or factor in the heat-killed virulent strains that can transform the harmless strain into a virulent one. The heat treatment likely denatures the proteins or breaks down the cell walls of the virulent strains, releasing this transforming factor.

James Watson, along with Francis Crick, is credited with determining the structure of the DNA molecule in the 1950s. Their discovery of the double helix structure of DNA revolutionized the field of genetics and earned them the Nobel Prize in Physiology or Medicine in 1962. Watson and Crick's work laid the foundation for our understanding of how genetic information is stored and transmitted, and their findings have had a profound impact on biology and medicine.

Cytosine is the correct answer because it forms a base pair with guanine through three hydrogen bonds. In DNA, guanine always pairs with cytosine, while in RNA, guanine pairs with uracil. Adenine pairs with thymine in DNA and uracil in RNA. Therefore, cytosine is the base that bonds to guanine.

Chase and Hershey did not use radioactive isotope Sulfur-35 to label DNA molecules. Instead, they used radioactive isotope Phosphorus-32 to label DNA molecules. Therefore, the statement is false.

Thymine is actually one of the four main bases found only in DNA, not in RNA. RNA contains a similar base called uracil instead of thymine. Therefore, the statement that thymine is found in both DNA and RNA is incorrect.

A DNA nucleotide is composed of a nucleobase, a five-carbon sugar, and one or more phosphate groups. The correct answer, 2-deoxyribose, is a five-carbon sugar that is found in DNA nucleotides. It is called "2-deoxyribose" because it is similar to ribose, another five-carbon sugar, but with one less oxygen atom. This difference in structure allows DNA to be more stable and less susceptible to degradation compared to RNA, which contains ribose. Therefore, 2-deoxyribose is an essential component of DNA nucleotides.

Rosalind Franklin made critical contributions to the understanding of molecular structures, particularly in the field of DNA. She used X-ray crystallography to study the structure of DNA, which provided key insights into its double helix structure. Additionally, her work on viruses helped in understanding their molecular structures. Coal and graphite are substances that have molecular structures, and Franklin's expertise in this area would have been relevant in studying their structures as well. However, there is no mention of Franklin's contributions to the understanding of RNA, fungi, or insects, so these substances are not included in the correct answer.