Question

s \(1-5\) to a concept it illustrates from a-e. 1\. Density shift experiments 2\. Discovery of an acidic substance that includes nitrogen … # Match the experiment described in #s \(1-5\) to a concept it illustrates from a-e. 1\. Density shift experiments 2\. Discovery of an acidic substance that includes nitrogen and phosphorus on dirty bandages 3\. "Blender experiments" that showed that the part of a virus that infects bacteria contains phosphorus, but not Sulfur 4\. Determination that DNA contains equal amounts of guanine and cytosine, and of adenine and thymine 5\. Discovery that bacteria can transfer a "factor" that transforms a harmless strain into a lethal one a. First experiments in identifying hereditary material b. Complementary base pairing is part of DNA structure and maintains a symmetrical double helix c. Identification of nuclein d. DNA, not protein, is the hereditary material e. DNA replication is semiconservative

Short answer

1.e, 2.c, 3.d, 4.b, 5.a

Step-by-step solution

Match Experiment to Concept

1. Density shift experiments illustrate the concept that DNA replication is semiconservative (e).

Match Experiment to Concept

2. Discovery of an acidic substance that includes nitrogen and phosphorus on dirty bandages correlates with the Identification of nuclein (c).

Match Experiment to Concept

3. 'Blender experiments' that showed that the part of a virus that infects bacteria contains phosphorus, but not Sulfur indicates the idea that DNA, not protein, is the hereditary material (d).

Match Experiment to Concept

4. Determination that DNA contains equal amounts of guanine and cytosine, and of adenine and thymine signifies Complementary base pairing is part of DNA structure and maintains a symmetrical double helix (b).

Match Experiment to Concept

5. Discovery that bacteria can transfer a factor that transforms a harmless strain into a lethal one represents First experiments in identifying hereditary material (a).

Key concepts

DNA replication

DNA replication is a vital process that allows cells to make an exact copy of their DNA. This is crucial during cell division when each new cell needs a full copy of the DNA to function properly. The replication process involves unzipping the double helix structure of DNA and creating two new strands, each using one of the old strands as a template. This ensures that the genetic information is conserved and transmitted accurately from one generation to the next.

One key aspect of DNA replication is known as semiconservative replication. This means that each of the two resulting DNA molecules contains one original strand and one new strand. The density shift experiments demonstrated this concept effectively by using isotopes to distinguish between the old and new strands of DNA. These experiments confirmed that DNA replication produces two strands that are hybrids of old and new DNA, solidifying our understanding of how genetic information is accurately passed on during cell division.

Complementary base pairing

Complementary base pairing is a fundamental principle of DNA structure, ensuring that the double helix remains stable and functional. In DNA, there are four types of nitrogenous bases: adenine (A), thymine (T), guanine (G), and cytosine (C). During DNA replication and transcription, these bases pair in a specific manner:

• Adenine pairs with Thymine (A-T)
• Guanine pairs with Cytosine (G-C)

This pairing is due to the hydrogen bonds that form between these bases and maintain the structural integrity of the DNA molecule.

The determination that DNA contains equal amounts of guanine and cytosine, and equal amounts of adenine and thymine, supports this principle. Known as Chargaff's rules, this concept emphasizes how the complementarity of base pairs contributes to the DNA's double helical structure, ensuring that the genetic code is consistent and can be accurately replicated between generations.

Hereditary material

The concept of hereditary material pertains to the understanding that DNA is the medium through which genetic information is inherited from one generation to the next. Each cell in an organism contains DNA that holds the instructions for that organism's development, functioning, and reproduction.

Experiments conducted during the mid-20th century, particularly the "blender experiments," were pivotal in establishing that DNA, and not protein, is the hereditary material. In these studies, key findings showed that only the DNA of viruses was necessary to infect and transform bacteria, indicating that DNA carried genetic information. This discovery revolutionized genetics, emphasizing the role of DNA in heredity and shaping future research in molecular biology.

Nuclein identification

Nuclein identification refers to the initial discovery and characterization of nucleic acids, the components of DNA and RNA. This journey began in the late 1800s with the discovery of a novel acidic substance while examining cells. This substance, found to contain nitrogen and phosphorus, was termed "nuclein."

This discovery was crucial as it set the stage for recognizing the chemical nature of genetic material. Over time, the understanding of nuclein evolved, and it was eventually identified as a collection of nucleic acids, which includes both DNA and RNA. The original observations, such as those from experiments focusing on dirty bandages, highlighted nuclein's prevalence in cell nuclei and laid the groundwork for discerning its key role in storing and transmitting genetic information.