Tuesday
May 9, 2017
I can:
Agenda
Catalyst

(10) Catalyst
(45) The History of Earth
(10) Questions Discussion
(15) IP: Early Earth
(5) Exit Ticket
explain how life has changed
since early Earth
1. How old is the earth?
2. Which type of organisms were
the first to develop (type of
cell? did they use oxygen?)
3. What was one interesting thing
you learned from the
documentary yesterday?
HW: IP: Early Earth
Tuesday
May 9, 2017
I can:
Agenda
Catalyst

(5) Catalyst
(60) The History of Earth
(10) Questions Discussion (?)
(15) IP: Early Earth
(5) Exit Ticket
explain how life has changed
since early Earth
1. Take out your “The Story of
Earth” questions
2. Be in your seat ready to start!
HW: IP: Early Earth
Exit Ticket Review
1. Which contributes most to the development
of drug-resistant bacteria?
A. drinking well water
B. overuse of antibiotics
C. frequent hand washing
D. failure to take vitamins
Exit Ticket Review
2. Which best explains why many insect
populations have become resistant to pesticides?
A. Insects are able to consume most commercial
pesticides.
B. Insects learn not to eat plants that have been
sprayed with pesticides.
C. Some insects have changed genetically and
are unaffected by pesticides.
D. Some insects have developed ribosomes,
which can render some pesticides inactive.
Exit Ticket Review
3. Bedbugs were nearly eradicated with insecticides in the early
1960s, but their numbers are increasing now. Modern bedbugs have
a thicker, waxy exoskeleton and resistance to common insecticides.
How did these changes most likely happen in bedbugs?
A. Offspring that benefited by inheriting several mutations outcompeted the offspring lacking the mutations. So, the population
changed.
B. Mutations caused by the insecticides caused the entire population
of bedbugs to genetically change at the same time.
C. Mosquitoes that had developed resistance to insecticides crossbred
with bedbugs, transferring resistance to the bedbug population.
D. Individual bedbugs that were not exposed to insecticides had time
to develop resistant traits. Their offspring out-competed those lacking
the traits, changing the population.
Exit Ticket Review
4. Through which process do scientists believe
MRSA, or methicillin-resistance Staphylococcus
aureus, most likely developed?
A. Natural selection occurred in mutated
bacterial DNA.
B. Prokaryotic bacteria evolved into eukaryotic
bacteria.
C. A virus infected the bacteria, changing its
genetic makeup.
D. Circular chromosomes in bacteria became
converted to linear chromosomes.
Exit Ticket Review
5. If a person is vaccinated one year against the
flu, what is the most likely reason why the person
has to get vaccinated again the next year?
A. The vaccine only works for a short period of
time.
B. The immune system rejects the vaccine after a
year.
C. The vaccine is ineffective in terminating the
entire virus.
D. The flu virus reproduces quickly and
accumulates mutations rapidly.
Exit Ticket Review
1. The breakup of Pangaea had which effect on the
subsequent history of animal speciation?
A. Animals had to become adapted to distinct
climates.
B. Animal diversity declined due to loss of
available territory.
C. Separated animal populations evolved
independently.
D. A single animal kingdom separated into
multiple, distinct phyla.
Exit Ticket Review
2. Mosquito fish found on the islands of the Bahamas live in various
isolated freshwater ponds that were once a single body of water.
When several male and female mosquito fish are taken from two
isolated ponds and placed into a single pond, the breeding
preference of each mosquito fish is for fish from its own original
pond. Which of these most likely resulted in this breeding
preference?
A. Availability of food influenced the breeding preferences of the
fish.
B. Competition for a suitable mate influenced the breeding
preferences.
C. Predators in the pond influence the breeding preferences of the
fish.
D. Speciation due to reproductive isolation influenced the breeding
preferences.
Exit Ticket Review
3. Two species of wood mouse live on opposite
sides of a river. Which is a likely reason they
have become separate species?
A. They mate at different times.
B. They have different courtship rituals.
C. Their gametes cannot fertilize each other.
D. Geography prevents mating from
occurring.
Hadean Eon
• Earth forms
• no oxygen in atmosphere
• constant volcanic activity
Archean Eon
• first anaerobic prokaryotes
• first photosynthetic prokaryotes
• oxygenation of atmosphere causes mass extinction
of anaerobic bacteria
Proterozoic Eon
•
•
•
•
first eukaryotes
first sexually reproducing organisms
first multicellular organisms
glaciation event
Phanerozoic Eon
• major diversification of
life
• major mass extinctions
eliminate 90% of
marine species
• modern era
The fossil record provides evidence about the history of
life on Earth and how different groups of organisms
have changed over time.
Fossils are remains of
dead organisms.
Paleontologists are
scientists who study
fossils. They look for
anatomical similarities
and differences
between the fossil and
living organisms.
The age of a fossil is very important and can be
determined in two ways:
1. Relative dating – allows paleontologists to estimate a
fossil’s age compared with that of other fossils.
youngest
fossils
oldest
fossils
The oldest fossils are
the furthest down.
The youngest fossils
are nearest to the
surface.
The age of a fossil is very important and can be
determined in two ways:
2. Absolute dating – scientists determine the exact age of
a fossil by using radiometric dating
Vocabulary Review
• anaerobic – without oxygen
• aerobic – with oxygen
prokaryotes are simple cells
with no nucleus or membranebound organelles
eukaryotes are larger, have a
nucleus and membrane-bound
organelles
The Earth formed 4.6 billion years ago.
• anaerobic atmosphere with simple organic
compounds
• water was present
How did life develop on
Earth?
The Miller-Urey experiment showed that the mixture of
complex organic compounds necessary for life could
form from simpler compounds present on primitive
Earth.
COMPLEX
COMPOUNDS!
Important events in the
development of life on Earth
3.5 billion years ago – the first anaerobic organism
formed.
The first organisms
were anaerobic
prokaryotes who were
able to thrive in the
harsh conditions of
early Earth.
3.4 billion years ago – anaerobic photosynthetic
organisms evolve.
What does
photosynthesis produce?
After the evolution of
photosynthetic bacteria, the
Earth’s atmosphere had much
more oxygen in it – it became
aerobic.
Then aerobic prokaryotes
developed.
2 billion years ago – aerobic eukaryotic cells developed.
• The endosymbiotic theory explains how the first
eukaryotic cells developed.
 a symbiotic relationship formed among several
different prokaryotic organisms
 prokaryotes became permanent organelles
Evidence of endosymbiosis:
1. mitochondria and chloroplasts contain their own DNA
2. the ribosomes of these two organelles are similar to
those found in bacteria
3. mitochondria and chloroplasts reproduce by binary
fission, just like bacteria
both bacteria and
mitochondria and
chloroplasts have circular
DNA
both bacteria and
mitochondria and
chloroplasts reproduce by
binary fission
??? years ago – sexual reproduction developed
• the crossing-over and shuffling of genes that occur
during sexual reproduction allowed for tremendous
diversity to develop
??? years ago – multicellularity evolves
• multicellular organisms consist of more than one cell
• this allows for cells in organisms to have specific jobs