Module 5 Flashcards
Who are Marshall and Warren?
Marshall and Warren discovered the cause of peptic ulcers. It was a bacteria known as H. Pylori.
What was thought to be the cause of peptic ulcers before the discovery by Marshall and Warren?
Spicy foods, stress, smoking and heavy drinking.
Why did Marshall and Warren’s method deviate from the conventional scientific method?
Marshall placed himself in harms way and voluntarily infected himself with the harmful bacteria as opposed to testing it on other subjects such as animals.
Why did Marshall and Warren’s experiment appear to not work initially?
The bacteria had not been left out for a long enough amount of time.
What was Von Helmont known for?
Von Helmont set out to determine how trees and plants grew / got their mass from.
What was the initial belief about how plants grew before Helmont’s findings?
It was believed that plants achieved their growth by ‘eating’ at the soil and it’s nutrients.
Why did Helmont conclude that trees don’t get their mass from the soil?
Helmont weighed the amount of soil that he had placed in a pot, planted a tree and took care of it for 5 years ensuring that no soil had left the pot or was added. After a 5 year period, he measured the mass of the tree to be 70 kilograms. However, the mass of the soil had only decreased by 60 grams. Which concluded that the mass of a tree does not receive it from the soil.
What was Von Helmont’s conclusion?
Trees get their mass from water.
What is Spencer most known for?
Spencer contributed to the invention of the Microwave oven.
State a new technology that came out of:
- Marshall and Warren
- Spencer
- Marshall and Warren paved the way for antibiotics for peptic ulcers.
- The microwave oven came out of Spencer’s findings.
Why weren’t Marshall and Warren’s findings initially supported by the scientific community?
It was believed that no bacteria could survive the conditions of the acidic stomach.
What may have been Marshall and Warren’s hypothesis?
Peptic ulcers are caused by the bacteria H. Pylori.
What may have been Van Helmont’s hypothesis?
Trees achieve their mass by ‘eating’ at the soil / nutrients from the soil.
What was Van Helmont’s conclusion?
Trees achieve their mass only from water.
However, this is partly correct as knowledge on gas and oxygen was limited at the time of his experiment.
What is Eratosthenes most known for?
Eratosthenes figured out a method to measure the circumference of the Earth by using the angle of shadow cast by a stick during summer solstice and the distance between Syene and Alexandria.
