LEC EXAM #1 CHP. 1

Question 1

Hook’s contribution :

Answer 1

• Cell theory that states “all cells arise from pre-existing cells”
• looked at dead cells in cork under a microscope

Question 2

Van Leeuwenhoek’s contribution:

Answer 2

First to use a powerful lens to see “animalcules” in a drop of rain water

Question 3

Redi’s contribution:

Answer 3

Tested spontaneous generation with:

• an open container
• cork-sealed container
• gauze-covered container

Question 4

Pasteur’s contribution:

Answer 4

• Swan-neck flask experiment that disproved spontaneous generation
• Strains of bacteria are unique
• Inventor of vaccines and fermentation

Question 5

Lister’s contribution:

Answer 5

Demonstrated that washing hands during surgery prevents disease and mortality in patients
-Performed first anti-septic surgery using phenol disinfectant

Question 6

Koch’s contribution:

Answer 6

• Individual strains of bacteria are unique

- Discovered anthrax, cholera, and tuberculosis

Question 7

Fleming’s work/contribution:

Answer 7

Discovered penicillin/antibiotics

Question 8

Margulis’s contribution:

Answer 8

-Responsible for endosymbiotic theory

Proposed that mitrochondrial and chloroplasts DNA are similar to bacterial/prokaryotic cell’s DNA

Question 9

What is spontaneous generation?

Answer 9

• Living material from non-living material
• Pasteur + Redi refuted this theory through their experiments and direct observation

Ex:

• Frogs come from mud
• Flies come from meat

Question 10

How did Redi and Pasteur refute the spontaneous generation theory?

Answer 10

Redi- through container experiment

Pasteur- through swan-neck flask experiment

Question 11

What is the germ theory of disease?

Answer 11

States disease may result from microbial infection

Question 12

Before the germ theory of disease, how did people explain illness?

Answer 12

• Spontaneous generation of living material from non-living material
• Malarie (bad air)

Question 13

Why did the swan neck experiment disprove spontaneous generation?

Answer 13

Bacteria could enter the flask but there is no air movement to get it over the hump of the flask, but if you break the neck of the flask then bacteria will enter and contaminate the water

Question 14

What is the endosymbiotic theory? (4)

Answer 14

Mitochondria and chloroplasts:

• Have similar DNA as bacterial cells DNA
• Have similar ribosomes as bacterial ribosomes
• Both perform binary fission
• Both cannot survive without the nucleus

Question 15

How does the endosymbiotic theory work?

Answer 15

Binary fission duplicates mitochondria= 2 identical mitochondria

**Cell is not duplicating, just mitochondria

Question 16

What are the only organelles, other than the nucleus, that has DNA?

Answer 16

Mitochondria and chloroplasts

Question 17

What is Koch’s postulates:

Answer 17

Allows one to determine if there is a relationship between a particular organism and a disease