🍥 mod 5 - scientific investigations!

Question 1

5.1.1

Who investigated peptic ulcers?

Answer 1

Barry Marshall & Robin Warren

Question 2

5.1.1

What initiated the peptic ulcer investigation?

Answer 2

They had observed small, curved and spiral-like bacteria present in the stomachs of people suffering from ulcers and gastritis.

Question 3

5.1.1

What was thought to be the cause of peptic ulcers?

Answer 3

• Lifestyle such as smoking
• Stress

Question 4

5.1.1

What is the actual cause of peptic ulcers?

** From their investigation

Answer 4

Helicobacter Pylori (H. Pylori) damages the lining of the stomach and intestine

Question 5

5.1.1

How did they carry out the peptic ulcer investigation? (Method)

Answer 5

1. Studied Biopsies of people with ulcers
2. Cultivated the bacteria in a lab
3. Self experimentation (Marshall drank broth contaminated with H. Pylori)

Question 6

5.1.1

Who investigated plant growth?

Answer 6

Van/Von Helmont

Question 7

5.1.1

What initiated the plant growth investigation?

Answer 7

Von Helmont wanted to research how plants gain their mass (their growth)

Question 8

5.1.1

What was thought to be the cause of plant growth?

Answer 8

Soil, plants absorbed nutrients and matter directly from it to grow

Question 9

5.1.1

What did he observe for the cause of plant growth?

** From his experiment

Answer 9

The plant gained 74kg and the soil only lost 57 grams , so the plants weight gain was from the water

Question 10

5.1.1

How did he carry out the plant growth investigation? (Method)

Answer 10

1. Weighed soil beforehand
2. Planted a Willow Tree in the dried soil for 5 years
3. Watered it with only rainwater and distilled water
4. Weighed it again after 5 years

Plant +74kg , Soil -57g

Question 11

5.1.1

Who investigated microwaves?

Answer 11

Percy Spencer

Question 12

5.1.1

What initiated the microwave investigation?

Answer 12

Spencer stood next to a magnetron which releases microwaves causing the chocolate in his pocket to melt. He then thought “Could radiowaves cook food?”

Question 13

5.1.1

How did he carry out the microwaves investigation?

Answer 13

He pointed microwaves at different food items surrounded by a metal box

Question 14

5.1.1

What did he observe from his microwave investigation?

Answer 14

Microwaves can cook food!

** This then lead to the construction of the first microwave :) **

Question 15

5.1.1

What is correlation?

Extra: What’s the difference between correlation and causation :)

Answer 15

Correlation is how two variables change eachother / How they are connected.

** E.g: Smoking correlates with alcoholism, but doesn’t cause it **

Question 16

5.1.1

What is causation?

Extra: What’s the difference between correlation and causation :)

Answer 16

Causation indicates that 1 event is the result of the occurence of another event.

** E.g: Hotter weather = More people getting sunburnt **

Question 17

Random Q!

What is an inference?

Answer 17

the process of drawing conclusions based on evidence and reasoning

Question 18

5.1.2 + 5.1.3

What is a hypothesis that Von Helmont may have had?

Answer 18

If there is water availability for a plant in soil then it will increase in mass because of water absorption from the soil.

** NOT from the soil itself!! **

** testing the conclusion of a previous investigation i think?? though i’m not sure :( **

Question 19

5.1.2 + 5.1.3

What is a hypothesis that Barry Marshall and Robin Warren may have had?

Answer 19

If a patient has peptic ulcers, then H.Pylori will be present because the bacteria is the cause for stomach ulcers.

** finding relationships or patterns in identified phenomena**

Question 20

5.1.2 + 5.1.3

What is a hypothesis that Percy Spencer may have had?

Answer 20

If food is in contact with microwaves then the food will cook because heat will be emitted

** utilising scientific knowledge and understanding to make more accurate predictions and develop new technologies**

Question 21

5.1.4

How did Barry Marshall and Robin Warren deviate from traditional models of scientific methodology?

Answer 21

1. They Self Experimented
2. Working backwards
3. They experimented before their understanding was actually developed / comprehensive

starting from Observation/Question > Report conclusion [look at pic]

https://learn.sasc.nsw.edu.au/courses/43219/discussion_topics/422331

Question 22

5.1.4

How did Von Helmont deviate from traditional models of scientific methodology?

Answer 22

1. Only had one sample and one trial, (No control, Not reliable)
2. Didn’t have a clear hypothesis
3. Bad Method, Bad Equipment

https://learn.sasc.nsw.edu.au/courses/43219/discussion_topics/422331

Question 23

5.1.4

How did Percy Spencer deviate from traditional models of scientific methodology?

Answer 23

1. He didn’t intend to exepriment on microwaves
2. Did not have a hypothesis, just “What if..” approach
3. He was more interested in applying his findings rather than trying to understand why it was happening

** Iterative approach, making modifications to his investigations impulsively (IDK :V)**

https://learn.sasc.nsw.edu.au/courses/43219/discussion_topics/422331

Question 24

5.2.1

What is Eratosthenes’ objective and what did he observe?

Answer 24

To demonstrate that the earth was round and he wanted to produce an accurate world map.

He observed that during summer solstice, syene produced no shadows but in alexandria a stick casted a shadow therefore earth is curved coz if it wasnt then there would be no shadow.

Question 25

# **5.2.1** What was Eratosthenes' method?

Answer 25

1. Measured the angle of the shadow cast at noon during summer (7.2 degrees) 2. Used professional walkers to walk from Alexandria to Syene to figure out the circumference of the earth

Question 26

# **5.2.1** Who investigated earth's roundness? ## Footnote bro...

Answer 26

Aristotle (384 - 322 BC) Suggested that the earth was sphereical Eratosthenes (240 B.C) ## Footnote ** Aristotle came first because B.C works backwards :) **

Question 27

# **5.2.1** What was Aristotles objective and what did he observe?

Answer 27

He wanted physical evidence of a spherical earth. He observed that the bottom of ships would disappear before the sails and when the sun sets, sunlight was still on top of mountains. ## Footnote ** Greek Philosophers believed the world could work by natural processes rather than Gods **

Question 28

# **5.2.1** What is the Doppler effect?

Answer 28

The change in perceived wave frequency during the relative motion between a wave source and its observer... When a sound source is approaching an observer the frequency will appear to be higher, When a sound source is moving away from an observer the frequency will appear to be lower | ** THERE IS NO ACTUAL CHANGE IN FREQUENCY, IT IS ONLY PERCEIVED CHANGE ## Footnote ** Proposed / Created by Christian Doppler **

Question 29

# **5.2.1** How is light frequency applied in astronomy?

Answer 29

Light sources moving away will have a lower frequency (RED SHIFTING) Light sources moving forward will have a higher frequency (BLUE SHIFTING) ## Footnote https://i.ytimg.com/vi/RlwXd2uFal0/maxresdefault.jpg

Question 30

# **5.2.1** What did Fraunhofer observe?

Answer 30

When he expanded the light spectrm, he saw that there were slices missing in the same spots everytime

Question 31

# **5.2.1** What did Fraunhofer discover?

Answer 31

That particular wavelengths of light were being absorbed by certain elements

Question 32

# **5.2.1** What did people think about oxygen and combustion in the 1700's?

Answer 32

That air and anything else that was combustible had a substance in it called "phlogiston" that would be released when burning, resulting in the material becoming lighter

Question 33

# **5.2.1** Who investigated oxygen and combustion?

Answer 33

Priestly

Question 34

# **5.2.1** What equipment did Priestly use in his Mercury Oxide (HgO) experiment?

Answer 34

* HgO * Glass ball jar * Burning lens * Sealed vessel * Water trough

Question 35

# **5.2.1** What was Priestly's method for the HgO experiment?

Answer 35

1. Heat mercury (Hg) in the presence of oxygen (O) and collect it in the glass ball jar (HgO) 2. Heat it by focusing sunlight with burning lens 3. Collect the oxygen gas with a water trough 4. Observe and repeat

Question 36

# **5.2.1** What did Priestly observe in his HgO experiment?

Answer 36

The effects of the released gas and found it was different from ordinary air, supporting combustion. The air made substances that were burned in it brighter and more readily.

Question 37

# **5.2.1** What did Priestly inference in his HgO experiment?

Answer 37

* Existence of a new gas, he thought the air was different from common air "dephlogisticated air" * Newfound gas supports combustion contradicting phlogiston theory and could sustain life cause it's breathable * Gas can be absorbed by certain substances * Fixed air (CO2) can't support life and combustion

Question 38

# **5.2.1** What equipment did Priestly use in his green plants experiment?

Answer 38

* Green plant * Bell jar * Water trough * Mercury trough * Thermometer * Glass tubes * Glass syringe / Gas measuring device * Controlled air sample

Question 39

# **5.2.1** What was Priestly's method for his green plants experiment?

Answer 39

1. Put green plant in airtight bell jar 2. Prep control group with jar and same air composition w/o plant 3. Put candle to facilitate photosynthesis 4. Monitor change: Air volume, Quality, Temperature variations 5. Collect samples of gas produced or consumed with glass syringe 6. Measure the volume of gas collected, compare to the initial air with the container ## Footnote ** When does the mouse come into the equation?? I don't know... I'm just doing my job ;0 **

Question 40

# **5.2.1** What did Priestly observe in his green plants experiment?

Answer 40

* Reduction of CO2 over time * Increase of O2 * Life can be sustained with green plant because he put a mouse in there

Question 41

# **5.2.1** What did Priestly inference in his green plant experiment?

Answer 41

* Green plant = reduction of fixed air (CO2) and increase in volume of pure air (O2) * ESPECIALLY in the presence of a light source

Question 42

# **5.2.2** What is a Primary investigation?

Answer 42

An investigation done directly by the scientists ## Footnote ** E.g Marshall and Warren cause Marshall drank the broth **

Question 43

# **5.2.2** What is fieldwork?

Answer 43

Scientists make direct observations, they're looking and seeing what is happening

Question 44

# **5.2.2** What is modelling?

Answer 44

modelling is trying to represent or show how something works ## Footnote ** E.g Physical models, Computer models **

Question 45

# **5.2.2** What are surveys?

Answer 45

A series of questions, used to collect data from a large selection of people

Question 46

# **5.2.2** What are simulations?

Answer 46

Recreations of something happening