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
Layered rock that formed from the activities of prokaryotes that bind thin films of sediment together.
stromatolites
Prokaryotes appeared ___ BYA
Eukaryotes appeared ____ BYA
Multicellular organisms appeared ____ MYA
Colonization of land occurred ____ BYA
3.5
1.5
800
475
The cambrian explosion is a huge diversification of life that occurred ____
~500 BYA
Various events contributed to the diversification of life
Evolution of the Eukaryotic Cell
Development of the ____
Formation of the ____
Endoplasmic reticulum
Nuclear envelope
The internal membrane system of eukaryotic cells, allows for specialization of different functions
ER
An aerobic bacterium established residence within a larger host cell eventually giving rise to mitochondria
Endosymbiosis
What causes specialization of cells ?
Expression of different genes
Allows specialization of cells and coordination of activities among cells
Multicellularity
Multicellularity evolved _____
independently several times
Coordination of cellular activities requires ____
communication among cells via chemical signals
Generates genetic diversity due to the formation of new allele combinations
Sexual reproduction
Greater genetic diversity leads to increased pace of
evolution
Led to the separation of populations and new selection pressures that favored certain organisms over others
Geologic and climatic changes
Evolution has generated millions of species however
most are extinct
Scientists estimate that currently earth has about ____ living species
10 million
The science of identifying, naming, and classifying organisms
Taxonomy
Taxonomy involves classifying organisms into groups that are increasingly more
inclusive
HUMANS Species Genus Family Order Classes Phylum Kingdom Domain
S Homo sapiens G Homo F Hominidae (the great apes) O Primates C Mammals P Cordata (vertebrates) K Animalia (all animals) D Eukarya
Organisms originate from ____
ancestral forms
How organisms are grouped should reflect their place within the ____
evolutionary tree of life
Phylogenetic classifications reflect the evolutionary relationships among organisms. The aim is to classify organisms based on ____
how long ago they separated from a common acestor
Organisms with many features in common separated _____
recently and vice versa
Similarities due to convergent evolution.
Analogy
Similar selection pressures resulted in ____
development of similar structures and morphologies
Similarity in characteristics resulting from a shared acestry
Homology
Different types of data are used to construct phylogenetic trees such as
morphological data
biochemical data
molecular data
Using various types of data scientists have classified organisms into two domains of prokaryotic organisms ____ and ____ and one domain that includes all Eukaryotic organisms
Eubacteria and Archaea
Eukarya are more closely related to ___than to ____ because
Archaea
Eubacteria
The group that includes the ancestral species and all its descendants
Monophyletic group (clade)
An ancestor but not all of the descendents
Paraphyletic group
Eubacteria, archaea, plants, fungi, and animals are a _____, but protists are ____
monophyletic groups
paraphyletic
