Cells 1.5 Origin of cells Flashcards Preview

Biology 1. Cells > Cells 1.5 Origin of cells > Flashcards

Flashcards in Cells 1.5 Origin of cells Deck (8)
Loading flashcards...

How did Pasteur disprove the spontaneous cell theory?

The spontaneous cell theory, proposed that cells just spontaneously appear. Yet, Pasteur's experiment proved that bacteria could only come from other bacteria. This means that cells can only come from preexisting cells.


Where did the first cell come from?

The first cell is an exception to Pasteur's theory as the first cell is an emergent property of non living chemicals.


If the first cell was created through non-living chemicals, can this still happen today?

No, this can no longer happen today because our environment has become to sterile. This means that even if the chemicals existed, they would probably be eaten by some of our bacteria today.


How did mitochondria and chloroplasts become part of a eukaryotic cell?

The theory holds that mitochondria and chloroplasts started out as living bacteria inside of a eukaryote. As the relationship benefited both, it became permanent.


Why is it theorized that mitochondria and chloroplasts started out as bacteria inside of a eukaryote?

Mitochondria has its own DNA.
Mitochondria has 70S ribosomes like prokaryotes.
They are about the same size as prokaryotes.
They reproduce through a similar process of binary fission.


What is hypertonic?

solution of higher osmolarity than the tissue soaked in it


What is isotonic?

has same osmolarity as a tissue


What is hypotonic?

has lower osmolarity than the tissue