Biology Discoveries — Set 5

Correct Answer: A. Werner Arber

• **Werner Arber** = He discovered restriction enzymes, the 'chemical scissors' that cut DNA at specific sequences, essential for genetic engineering. • **1978** — Arber, Nathans, and Smith were awarded the Nobel Prize in this year for their discovery and application of restriction enzymes. • 💡 Wrong-option analysis: Daniel Nathans: he helped apply restriction enzymes to genetic studies; Hamilton Smith: he discovered the first type II restriction enzyme; Other than listed: Werner Arber is specifically listed.

Correct Answer: D. Marcello Malpighi

• **Marcello Malpighi** = He discovered Malpighian tubules, the excretory system in insects, and identified filtration units within the human kidney, both named in his honor. • **17th century** — Malpighi's detailed microscopical work on anatomy, including these discoveries, occurred primarily in the mid to late 17th century. • 💡 Wrong-option analysis: Jan Swammerdam: a pioneer in insect anatomy, but Malpighi named the tubules; Nehemiah Grew: known for his work in plant anatomy; Robert Brown: discovered the cell nucleus.

Correct Answer: C. DNA is the genetic material

• **DNA is the genetic material** = The Avery-MacLeod-McCarty experiment definitively proved that DNA, not protein, carries genetic information in cells. • **1944** — Oswald Avery and his team conducted this pivotal experiment in this year, transforming the field of genetics. • 💡 Wrong-option analysis: RNA is the genetic material: incorrect, RNA is genetic material for some viruses but not universally proven by this experiment; Lipids carry genes: incorrect, lipids are not genetic carriers; Proteins carry genes: this was a common belief before this experiment, which proved it wrong.

Correct Answer: C. Kary Mullis

• **Kary Mullis** = He developed the Polymerase Chain Reaction (PCR) technique, enabling rapid amplification of millions of copies of a specific DNA segment. • **1983** — Mullis developed PCR in this year, a technique now indispensable for forensic science, diagnosis, and genetic research; he received the Nobel Prize in **1993**. • 💡 Wrong-option analysis: James Watson: co-discovered the structure of DNA; Frederick Sanger: developed DNA sequencing methods; Craig Venter: known for human genome sequencing and synthetic biology.

Correct Answer: A. GFP (Green Fluorescent Protein)

• **GFP (Green Fluorescent Protein)** = Its discovery, from jellyfish bioluminescence, revolutionized biology by allowing researchers to visualize processes in living cells. • **2008** — Osamu Shimomura, along with others, was awarded the Nobel Prize in Chemistry in this year for the discovery and development of GFP. • 💡 Wrong-option analysis: Hemoglobin: a protein in red blood cells that carries oxygen, not related to jellyfish bioluminescence; Chlorophyll: the green pigment in plants for photosynthesis; ATP: adenosine triphosphate, the main energy currency of the cell.

Correct Answer: A. Georges Köhler

• **Georges Köhler** = Georges Köhler, along with César Milstein, developed the hybridoma technique for producing monoclonal antibodies. • **1975** — the hybridoma technique was developed to produce identical antibodies in large quantities. • 💡 Wrong-option analysis: César Milstein: He was a co-discoverer of monoclonal antibodies but not the specific answer indicated; All of the mentioned: Incorrect, as the specified correct answer is Georges Köhler alone; Paul Ehrlich: Known for his pioneering work in immunology and chemotherapy, but not for monoclonal antibodies.

Correct Answer: A. Barry Marshall

• **Barry Marshall** = Barry Marshall, with Robin Warren, discovered *Helicobacter pylori* as the bacterium causing stomach ulcers. • **2005** — Marshall and Warren received the Nobel Prize for their groundbreaking discovery. • 💡 Wrong-option analysis: Robin Warren: He was a co-discoverer of *Helicobacter pylori* but not the specific answer indicated; All of the mentioned: Incorrect, as the specified correct answer is Barry Marshall alone; Robert Koch: Famous for identifying causative agents of diseases like TB and cholera, not *H. pylori*.

Correct Answer: B. Sydney Brenner

• **Sydney Brenner** = Sydney Brenner significantly advanced the discovery of apoptosis or programmed cell death. • **2002** — Brenner, Horvitz, and Sulston shared the Nobel Prize for their discoveries concerning programmed cell death. • 💡 Wrong-option analysis: Robert Horvitz: A co-recipient of the Nobel Prize for apoptosis, but not the specific answer indicated; John Sulston: A co-recipient of the Nobel Prize for apoptosis, but not the specific answer indicated; Other than listed: Incorrect, as Sydney Brenner is listed and is the correct answer.

Correct Answer: A. Elizabeth Blackburn

• **Elizabeth Blackburn** = Elizabeth Blackburn, with her colleagues, discovered telomerase, the enzyme that protects the ends of chromosomes. • **2009** — Blackburn, Greider, and Szostak shared the Nobel Prize for their discoveries on telomeres and telomerase. • 💡 Wrong-option analysis: Carol Greider: A co-discoverer of telomerase, but not the specific answer indicated; Jack Szostak: A co-discoverer of telomerase, but not the specific answer indicated; Other than listed: Incorrect, as Elizabeth Blackburn is listed and is the correct answer.

Correct Answer: B. Joshua Lederberg

• **Joshua Lederberg** = Joshua Lederberg discovered plasmids as independent DNA molecules in bacteria. • **1952** — Lederberg coined the term 'plasmid' to describe genetic material outside the main chromosome. • 💡 Wrong-option analysis: Oswald Avery: Known for his 1944 experiment proving DNA is the genetic material, not plasmids; Francis Crick: Co-discoverer of the double-helical structure of DNA, not plasmids; James Watson: Co-discoverer of the double-helical structure of DNA, not plasmids.