BI.7A

During a biology class, Adrian and Tori were discussing the four nucleotide bases found in DNA. Can you help them identify the correct ones?

• Adenine, Thymine, Cytosine, Guanine

• Adenine, Uracil, Cytosine, Guanine

• Thymine, Uracil, Cytosine, Guanine

• Adenine, Thymine, Uracil, Guanine

Answer explanation

The four nucleotide bases in DNA are Adenine, Thymine, Cytosine, and Guanine. This is the correct choice, as Uracil is found in RNA, not DNA.

Markeis and Tori are studying genetics in their biology class. They learn that a change in the nucleotide sequence of DNA can lead to a change in an organism's trait. How does this happen?

• A change in the nucleotide sequence can alter the protein produced, potentially changing the trait.

• A change in the nucleotide sequence has no effect on the organism's traits.

• A change in the nucleotide sequence only affects the organism's lifespan.

• A change in the nucleotide sequence only affects the organism's size.

Answer explanation

A change in the nucleotide sequence can lead to a different amino acid sequence in a protein, which may alter its function. This alteration can affect traits, making the first answer choice correct.

Tags

NGSS.HS-LS1-1

NGSS.HS-LS3-2

During a science class, Adalynn and Malik were discussing the structure of DNA. Which component of DNA forms the backbone of the DNA structure?

• Nucleotide bases

• Phosphate and sugar molecules

• Proteins

• Lipids

Answer explanation

The backbone of DNA is formed by phosphate and sugar molecules, which create a structural framework for the nucleotide bases to attach. This arrangement is crucial for the stability and integrity of the DNA molecule.

Adalynn and Malik are learning about how cells make proteins. Can you describe the process by which DNA sequences are translated into proteins?

• DNA is directly converted into proteins by ribosomes.

• DNA is transcribed into RNA, which is then translated into proteins.

• DNA is translated into proteins without any intermediate steps.

• DNA is converted into lipids, which then form proteins.

Answer explanation

The correct process involves DNA being transcribed into RNA, which serves as a template for translation into proteins. This two-step process is essential for gene expression, unlike the incorrect options that misrepresent the flow of genetic information.

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NGSS.HS-LS1-1

Adalynn and Malik are discussing how DNA might have originated. They explore the scientific explanation that suggests DNA originated from simpler molecules through chemical evolution. What is the most accurate description of this process?

• DNA was created in its current form and has not changed.

• DNA originated from simpler molecules through a series of chemical reactions over time.

• DNA was formed by the combination of proteins and lipids.

• DNA was formed by the fusion of different organisms.

Answer explanation

The correct choice states that DNA originated from simpler molecules through chemical reactions over time, aligning with the scientific view of chemical evolution, unlike the other options which suggest static or incorrect origins.

During a science class, Tori and Malik were discussing the structure of DNA. What is the role of hydrogen bonds in the structure of DNA?

• They connect the sugar and phosphate groups.

• They hold the two strands of DNA together by connecting the nucleotide bases.

• They form the backbone of the DNA molecule.

• They are responsible for the replication of DNA.

Answer explanation

Hydrogen bonds are crucial in DNA as they connect the nucleotide bases of the two strands, holding the double helix structure together. This interaction is essential for maintaining the stability of DNA.

Adrian and Tori are studying how mutations in DNA can affect protein synthesis and lead to genetic disorders. What conclusion might they reach?

• Mutations always improve protein function and prevent disorders.

• Mutations can change the amino acid sequence of a protein, potentially leading to disorders.

• Mutations have no effect on protein synthesis.

• Mutations only affect the physical appearance of an organism.

Answer explanation

Mutations can alter the DNA sequence, leading to changes in the amino acid sequence of proteins. This can disrupt normal protein function and potentially result in genetic disorders, making this choice correct.

Tags

NGSS.HS-LS1-1

NGSS.HS-LS3-2

Adalynn and Zach are learning about genetics in their biology class. They are curious about how the sequence of nucleotide bases in DNA affects living organisms. What is the significance of this sequence?

• It determines the sequence of amino acids in proteins.

• It determines the color of an organism.

• It determines the size of an organism.

• It has no significance.

Answer explanation

The sequence of nucleotide bases in DNA is crucial because it encodes the information needed to determine the sequence of amino acids in proteins, which are essential for the structure and function of all living organisms.

Tags

NGSS.HS-LS1-1

Adalynn and Malik are building a model of DNA for their biology class. They need to identify the type of bond that connects the phosphate group to the sugar in the DNA backbone. Can you help them?

• Hydrogen bond

• Ionic bond

• Covalent bond

• Metallic bond

Answer explanation

The bond connecting the phosphate group to the sugar in the DNA backbone is a covalent bond. This strong bond forms the backbone structure, allowing DNA to maintain its integrity and stability.

Adrian and Tori are learning about how cells divide and pass on genetic information. Discuss the role of DNA replication in this process.

• DNA replication is not involved in genetic transmission.

• DNA replication ensures that each new cell receives an exact copy of the DNA.

• DNA replication only occurs in response to environmental changes.

• DNA replication is responsible for the production of energy in cells.

Answer explanation

DNA replication is crucial for genetic transmission as it ensures that each new cell receives an exact copy of the DNA, maintaining genetic continuity across generations.

Tags

NGSS.HS-LS3-2