Biology Flashcards
What is the definition of a scale
a comparison between the size of a drawing and the actual size
The powers of the objective lens is __x for low power, __x for medium power, and __x for high power
4x
10x
40x
The eyepeice / ocular lense is always __x
10x
Field of View can be described in terms of Field ______ and Field ______
DIameter; Area
Why is scientific advancement sometimes slowed
People find it hard to accept new ideas despite scientific evidence
What did Galileo claim that caused him to be imprisoned by the catholic church in the 1630s
That the earth revolved around the sun
Why did the church later accept Galileos claim
Because they believed that since God created man, he should be at the center of the universe
What is Spontaneous Generation
the belief that living things can come from non living matter
What did Francisco Redi do?
Set up an experiment to illustrate maggots (a living thing) did not grow spontaneousley out of raw meat (non-living thing)
How did Redi prove his theory
He set out two flasks one with access to air and flies, and one that was sealed, only the flask open to air and flies had maggots
Redi thought that this experiment proved that spontaneous generation was wrong, but what did other scientists think
That it proved that spontaneous generation is true because air was a necessary ingredient to have maggots
What did John Needham do
he wanted to prove the existence of life forces by boiling chicken broth and placing it in a sealed flask, he found that microorganisms still appeared because the broth was not heated long enough
What did Lazzaro Spallanzani do
repeated Needhams experiment but in a vacuum because it removed air from the flask before it was sealed, no microorganisms appeared.
What did Louis Pasteur do?
Set up two flasks each with meat broth, he heated the flasks to sterilize them. The necks of the flasks were bent so air could enter but not dust. Neither flasks had microbial growth
Louis Pasteur did two other experiments with the meat broth, what were they?
Experiment 1: Broke off the neck of the flask giving it access to air and dust
Experiment 2: He left the neck intact, where dust was stuck inside.
Microrganisms appeared in flask 1 but not two
