Lectures 1&2 Flashcards
Prokaryotes include what domain(s)
Eubacteria and Archaea
Eukaryotic organisms include what domain(s)
Eukarya
Name the four kingdoms within Domain Eukarya
Kingdom Protista
Kingdom Fungi
Kingdom Virdiplantae
Kingdom Animalia
The earth formed as a hot mass of molten rock about ___ billion years ago.
4.8
As the earth cooled water condensation resulted in the formation of ____ that contained many ____
oceans
inorganic molecules
Hypotheses to explain the origins of life: Life or organic molecules may have come to Earth from _____
some other planet via a meteorite colliding with earth
Hypotheses to explain the origins of life: life arose spontaneously in the _____
oceans, combination of compounds such as methane and ammonia which formed more complex molecules
In 1953 Miller and Urey did an experiment that did what
Reproduced the early Earth atmosphere and used electrodes to stimulate lightening
During Miller and Urey’s experiment what was generated in their apparatus
Small organic molecules including amino acids, and nitrogenous bases
On hot surfaces monomers can spontaneously form ____.This means amino acids will form ___ and nucleotides will form ____
Polymers
polypeptides
nucleic acids
Origin of self replicating molecules: Some RNA molecules have catalytic activity this means they
make copies of themselves
Formation of pre-cells: Some lipids and proteins can spontaneously form ____, these perhaps accumulated RNA
Vesicles
Formation of pre-cells: Vesicles with organic molecules inside eventually became ___. Over millions of years these vesicles may have acquired other features such as ___
living cells with the ability to reproduce
the ability to use glucose as an energy and carbon source
If scientists built a protobiont with self-replicating RNA and metabolism, would that prove that life began in this manner?
No, it proves that it is possible but not necessarily the way that it happened.
Based on the fossil record, life started between ____ and ___
3.8 and 3.2 BYA
A rock model of the original organisms or part of it
Fossil
How is the age of fossils determined?
By dating the rocks in which fossils are found gives the fossils age
When rock form from ___ some elements in the rock have ____
magma
radioactivity
The radioactivity of these elements ___ over time at a certain rate
decays
The more radioactive something is the ___ it is
younger
The less radioactive something is the ___ it is
older
With micro-fossils it is often difficult to ascertain that it is a true fossil or ____
something else within the rock
Organisms have a higher ____ ratio than that found in air or in mineral rocks
C12/C13
Evidence of ancient life can also be found in ____ some of which are 2.7 BY old
stromatolites
