Scientific Discoveries and Their Methodologies (copy)

What did Barry Marshall and Robin Warren propose in 1982 regarding peptic ulcers?

They proposed that Helicobacter pylori (H. pylori) was the actual cause of peptic ulcers.

What were the initial believed causes of peptic ulcers before 1982?

They were thought to be caused primarily by stress, spicy foods, and excess stomach acid.

What methodology did Barry Marshall use to establish a link between H. pylori and gastritis?

He drank a culture of H. pylori to demonstrate a direct link.

What was the impact of Marshall and Warren's discovery on the treatment of peptic ulcers?

Antibiotics became the primary treatment instead of long-term use of acid-reducing medications.

What did Jan Baptista van Helmont conclude about the source of a plant's mass?

He concluded that the mass of the tree primarily came from water.

What experiment did Van Helmont conduct to determine plant growth sources?

He planted a willow tree in 90 kg of dried soil and measured the mass after five years.

How did Percy Spencer discover the heating effect of microwaves?

He observed that a chocolate bar melted in his pocket due to radar waves.

What invention arose from Percy Spencer's observations of microwaves?

The first commercial microwave oven.

What measurement technique did Eratosthenes use to estimate the Earth's circumference?

He measured the angle of the shadow cast in Alexandria while noting sunlight in Syene.

What was Eratosthenes' estimated circumference of the Earth?

Approximately 40,000 km.

What principle explains changes in pitch of sound waves as a source moves relative to an observer?

The Doppler Effect.

What impact did Christian Doppler's work have on technology?

It underpins foundational technologies like radar, sonar, and medical imaging.

What did Joseph Priestley discover regarding combustion in the 18th century?

He identified oxygen as essential for combustion and respiration.

Which gas theories did Joseph Priestley's discovery challenge?

He challenged the phlogiston theory.

What modern techniques are used to recreate Earth's geological history?

Modern computer simulations using large datasets and mathematical models.

What impact do modern climatic simulations have on our understanding of Earth?

They enhance climate change forecasts and disaster preparedness.

What discovery did Rosalind Franklin contribute to in determining DNA structure?

Her X-ray diffraction 'Photo 51' showed the X-shaped pattern of DNA.

What did the discovery of DNA's double-helix structure elucidate?

It clarified DNA replication processes.

What was the purpose of Geiger counters in detecting radioactivity?

They measure ionizing radiation through electric pulses.

What important discoveries emerged from early radioactivity research?

The discoveries of radioactivity and subatomic particles.

What energy processes are involved in nuclear reactions?

Nuclear fission and fusion produce immense energy.

What application uses controlled radiation to battle cancer?

Radiotherapy.

What are genetically modified organisms (GMOs) used for?

To enhance food production efficiency.

What does CRISPR technology enable in genetic research?

It allows precise DNA edits to combat genetic disorders.

What foundational laws did Newton formulate impacting civil engineering?

Newton's Laws of Motion.

How do shock-absorbing materials help in earthquake-resistant structures?

They reduce structural damage during earthquakes.

What is the role of base isolators in earthquake-resistant design?

They allow buildings to move independently during seismic activities.

What are limitations of earthquake-resistant technologies?

High costs of safety technologies in poorer communities.