Unit 3: Ch 8 Quiz (Fall 2014)

The correct answer is "Phosphate" because in a nucleotide, the phosphate group is the part labeled A. A nucleotide is composed of three main components: a phosphate group, a ribose sugar, and a nitrogen base. The phosphate group is responsible for linking nucleotides together to form the backbone of DNA and RNA molecules.

The part labeled B in this question is the Ribose Sugar. Ribose is a type of sugar that is a component of nucleotides, which are the building blocks of nucleic acids like DNA and RNA. Ribose sugar is a five-carbon sugar that forms the backbone of RNA molecules. It is important for the structure and function of RNA, as it helps to stabilize the molecule and play a role in the formation of the RNA double helix.

Replication is the correct answer because it refers to the process of making an exact copy of a DNA molecule. During replication, the DNA molecule unwinds and each strand serves as a template for the synthesis of a new complementary strand. This results in two identical DNA molecules, each containing one original strand and one newly synthesized strand. Transcription, on the other hand, is the process of synthesizing RNA from a DNA template, while translation is the process of synthesizing proteins from RNA. Mutation refers to a change in the DNA sequence.

The diagram represents a monomer, which is a single unit that can combine with others to form a larger molecule. In this case, the monomer is specifically called a nucleotide. Nucleotides are the building blocks of nucleic acids, such as DNA and RNA. They consist of three components: a phosphate group, a ribose sugar, and a nitrogen base. Therefore, the correct answer is nucleotide.

In the context of nucleotides, nitrogen base refers to the part of the nucleotide molecule that contains nitrogen atoms and is responsible for the coding of genetic information. It is one of the three main components of a nucleotide, along with the phosphate group and the ribose sugar. Therefore, the part labeled C in this question is the nitrogen base.

Adenine and thymine are complementary base pairs in DNA, meaning that they always pair together. Similarly, guanine and cytosine are also complementary base pairs. Therefore, the correct answer is cytosine.

Thymine and adenine are a pair of complementary bases because they form a base pair in DNA. In DNA, thymine always pairs with adenine through hydrogen bonding, forming two hydrogen bonds between them. This base pairing is essential for the structure and replication of DNA, as it ensures that the genetic information is accurately copied and transmitted.

The complementary strand of DNA reads ATAGCTA because in DNA, adenine pairs with thymine (A-T) and cytosine pairs with guanine (C-G). So, for each base in the original strand, the complementary strand will have the corresponding base pair. In this case, T pairs with A, A pairs with T, C pairs with G, G pairs with C, and so on. Therefore, the correct answer is ATAGCTA.

The process illustrated in the diagram is replication. Replication is the process by which DNA molecules are copied to produce two identical DNA molecules. This process occurs during cell division and is essential for the transmission of genetic information from one generation to the next. In replication, the DNA double helix unwinds and each strand serves as a template for the synthesis of a new complementary strand. This results in two identical DNA molecules, each consisting of one original strand and one newly synthesized strand.

Watson and Crick, along with the assistance of Rosalind Franklin, proposed that DNA has the shape of a double helix. This means that DNA is structured as two strands that twist around each other in a spiral shape. This discovery was crucial in understanding the structure and function of DNA, as it allowed scientists to comprehend how genetic information is stored and transmitted within living organisms. The shape of a double helix also provided insights into how DNA replicates and how genetic traits are inherited.

Transcription, the process of creating an mRNA molecule using DNA as a template, occurs in the nucleus. This is where the DNA is located and where the necessary enzymes and other proteins needed for transcription are present. The mRNA molecule is then transported out of the nucleus and into the cytoplasm, where it can be further processed and translated into a protein by the ribosomes.

A set of three nucleotides on mRNA that codes for a specific amino acid is referred to as a codon. Codons are the basic units of the genetic code and they determine the sequence of amino acids in a protein. They act as a template for protein synthesis during translation. The correct answer is codon.

The statement "The kinds of sugar in the nucleotides of DNA and RNA differ" is true. DNA contains deoxyribose sugar in its nucleotides, while RNA contains ribose sugar in its nucleotides. This difference in sugar composition is one of the key distinctions between DNA and RNA.

The mRNA strand with the sequence AGUACA can be produced from the DNA sequence TCATGT. In mRNA, the nucleotide T is replaced with U, so the DNA sequence TCATGT would be transcribed into the mRNA sequence UCACAU. By comparing this mRNA sequence with the given mRNA sequence AGUACA, it can be observed that they match, confirming that the DNA sequence TCATGT is the correct answer.

A mutation in a person's skin cells is least likely to result in the person's offspring having mutated skin cells. Mutations in somatic cells, such as skin cells, are not passed on to offspring as they do not affect the genetic material in the person's reproductive cells (sperm or eggs). Offspring inherit genetic information from their parents' germ cells, not from somatic cells. Therefore, it is unlikely that a mutation in a person's skin cells would have any direct impact on the genetic makeup or mutations in their offspring's skin cells.

Messenger RNA is formed in the process of transcription. Transcription is the process by which the DNA sequence in a gene is copied into a complementary RNA molecule. During transcription, an enzyme called RNA polymerase binds to the DNA and synthesizes a single-stranded RNA molecule, known as messenger RNA (mRNA). This mRNA molecule carries the genetic information from the DNA to the ribosomes, where it is used as a template for protein synthesis in the process of translation. Therefore, transcription is the correct process in which messenger RNA is formed.

Translocation is the correct answer because it refers to the chromosome abnormality that occurs when a part of one chromosome breaks off and becomes attached to a different chromosome. This can result in genetic material being exchanged between chromosomes, potentially leading to genetic disorders or abnormalities.

The nucleotide triplet on tRNA that complements a codon is called an anticodon. This is because the anticodon sequence on tRNA pairs with the codon sequence on mRNA during translation. The pairing between the anticodon and codon is crucial for determining the specific amino acid that will be added to the growing polypeptide chain.

The given sequence of mRNA is GCATUGUAA. In the genetic code, a stop codon signals the end of protein synthesis. The stop codons are UAA, UAG, and UGA. Since the given sequence includes the stop codon UAA, it means that the protein synthesis would terminate at that point. Therefore, this sequence codes for only 2 amino acids before the termination of protein synthesis.

Ribosomes are cellular structures responsible for protein synthesis. They are composed of ribosomal RNA (rRNA) and two protein subunits. The rRNA provides the structural framework for the ribosome, while the protein subunits play a role in catalyzing the formation of peptide bonds during protein synthesis. Together, rRNA and protein subunits form the functional ribosomes that are essential for protein production in cells.

DNA and RNA are both nucleic acids involved in genetic information storage and transfer. DNA is double-stranded, consisting of two complementary strands that are held together by hydrogen bonds. RNA, on the other hand, is usually single-stranded. Therefore, the analogy suggests that just as DNA is double-stranded, RNA is single-stranded. The other options, ribose and triple strand, do not accurately represent the relationship between DNA and RNA. Double helix is a term used to describe the structure of DNA, but it does not directly relate to the comparison between DNA and RNA.

The sides of the DNA double helix are made up of joined sugars and phosphates. The sugar molecule in DNA is deoxyribose, which is joined to a phosphate group to form a sugar-phosphate backbone. This backbone provides stability and support to the DNA molecule. The nitrogenous bases (adenine, thymine, cytosine, and guanine) are attached to the sugar molecules and project inward, forming the "rungs" of the DNA ladder. Therefore, the correct answer is joined sugars and phosphates.

Each organism of the same species has the same number of chromosomes in each cell. This statement is true because chromosomes carry the genetic information of an organism and are responsible for passing on traits from one generation to the next. In order for organisms of the same species to reproduce successfully, they must have the same number of chromosomes to ensure that the genetic information is properly transmitted. This allows for the maintenance of genetic stability within a species.

The original sequence "TACGCG" has six nucleotides, while the mutated sequence "TCGCGT" has only five nucleotides. One nucleotide, "A", has been deleted from the original sequence, resulting in a shorter mutated sequence. Therefore, the type of mutation that has occurred in this piece of DNA is a deletion.

Transcription is the process of synthesizing mRNA from DNA, while translation is the process of synthesizing protein from mRNA. Therefore, the correct answer is protein.