Jordan Biosciences II Final Part 2

Morphological differences distinguishing the species

Differences in the geographic distribution of the species

The ability of individuals to successfully breed with each other

The species in the two areas have become separated by convergent evolution

The climates of the two regions are similar

India is in the process of separating from the rest of Asia

Life in India was wiped out by ancient large-scale volcanic eruptions

India was a separate continent until about 55 million years ago.

Discovery of a crater dating to 65 million years ago

Shock crystal distributions

A layer of the rare earth element iridium in deposits dating to the time of that mass extinction

Caves near Lascaux in France have sketches, engravings and paintings depicting events around the time of the event

Results of computer modeling of volcanic and nuclear incidents

Fossils that date to 2.5 billion years old include prokaryotes, and eukaryotes including multicellular organisms

Limestone deposits called stromatolites, accumulated by cyanobacteria, are known as fossils and are still being formed today

Cells with a nucleus predate cells with mitochondria

The first photosynthetic organisms on earth must have been prokaryotes

The Burgess Shale is known for its fossil demonstration of the Cambrian Explosion

They are representatives of the Bacteria domain

There is genetic evidence supporting the theory that today's cyanobacteria are similar to the ancestors of chloroplasts

They are photosynthetic

Their metabolism results in the production of molecular oxygen from water

They are chemoautotrophs

The bowers are used by the birds as refuges from predators

The bowers are used by the birds as protective areas for rearing young

The populations of bower birds appear to be reproductively isolated

If the birds diverge into two distinct species, we will be able to attribute it to kin selection

While the bird populations differ regarding the bower construction and ornamentation, the two populations, never the less, continue to interbreed because sexual attraction relies on olfactory cues and despite the divergence in bower characteristics via what we refer to as genetic drift, the two populations remain part of a single species

They use different odors to advertise to mates

They have different courtship dances

They make different noises by rubbing body parts in different ways

They find different fruits acceptable as stages for courtship dances

The fruits that they use mature at different times of the year

The species will increase its risk of going extinct because there are fewer potential mates since individuals only tend to mate with similarly appearing individuals and avoid mating with a large proportion of the population

The species will divide into two distinct species

The inbreeding will result in a higher-than-expected number of abnormal offspring

Whereas all eukaryotes have mitochondria (or remnants thereof), not all eukaryotes have chloroplasts

Chloroplasts have ribosomes that are more similar to prokaryotic ribosomes than they are to ribosomes found in the cytosol of the eukaryotic cell

The mitochondrial ribosomes vary extensively from one group of eukaryotes to another, but they are generally more similar to prokaryotic ribosomes than to their counterparts in the eukaryotic cytoplasm

Prokaryotes lack a cell membrane

Only prokaryotes have cell walls

Only eukaryotes can engage in sexual reproduction

Only eukaryotes have mitochondria

Only eukaryotes have ribosomes

There is less diversity in the mitochondrial DNA of finches on San Cristobal than among their finch ancestors

There is more diversity in the mitochondrial DNA of finches on San Cristobal than among their finch ancestors remaining in the Americas

There is the same level of diversity in the mitochondrial DNA of finches on San Cristobal as is found among their finch ancestors remaining in the Americas

Genetic recombination only occurs in eukaryotes

While all eukaryotes have DNA as their genetic material, some prokaryotes use DNA and others use RNA

Only prokaryotes have plasmids

Genetic recombination as a result of transformation is more likely in prokaryotes than eukaryotes

Meiosis results in greater measures of genetic recombination in prokaryotes than in eukaryotes

They colonized the Isle ata time when there was no water in what is now the English Channel

Deer on the Isle have evolveda diminished stature, compared with their ancestors and contemporaneous populations in England and on the mainland

Deer on the Isle are geographically isolateed from those in England and illustrate how allopatric speciation might occur

They are found in New Zealand because the island was once part of a larger land mass which included what is now Europe

They are representatives of the Archaea

They can be found in 2.5 billion years ago sedimentary rocks

They are formed of cyanobacteria

Their metabolism results in the production of molecular oxygen from water

They are photoautotrophs

Existed over 1 b.y.a.

Contained mitochondria

Were anaerobic

Would be classified today as algae

Photosynthetic protists were primarily responsible for the transition

Once the concentrations of oxygen increased sufficiently in the atmosphere, aquatic environments then became perfused with increasing levels of dissolved oxygen

Evidence of when the environment was oxidizing can be found in iron oxide deposits in rocks

The transition to an oxidizing environment would have been lethal to many prokaryotes

The evidence that the world's atmosphere approximately 2.7 billion years ago was becoming an oxidizing atmosphere comes from the appearance of cyanobacteria in the fossil record 2.7 billion years ago

Since DNA codes for enzymes, and enzymes are essential for cells to function, DNA must have been the first information-bearing molecule used by early life forms

That RNA can act as a catalyst may help explain how relatively complex organic molecules could form on prebiotic earht in the absence of enzymes

Since RNA is the information-bearing molecule that is translated into the amino acid sequnces of enzymes, RNA must have predated the appearance of molecules having enzymatic activity on prebiotic earth

Since proteinaceous enzyme are necessary to synthesize RNA and DNA, proteinaceous enzymes must have been present on prebiotic earth prior to the appearance of an information-bearing molecule

Eukaryotes have subcellular organelles with genetic make-ups resembling that of prokaryotes

Some prokaryotes have RNA as their genetic material as do mitochondria and plastids

Some subcellular organelles can divide by simple fission as do prokaryotes

Some subcellular organelles are about the same size as prokaryotes

Evidence that the Archaea are more closely related to the Eukarya than to the Bacteria includes the observation that of the two only Archara and Eukarya have histones associated with their genetic material

The Archaea include methanogens that are capable of living in environments rich in methane and metabolizing the gas as a carbon source. This is in marked contrast to photosynthetic plants, for example, that "fix" their carbon from CO2 in the air.

Archaea(bacteria) and (eu)bacteria differ because members of the Archaea customarily lack cell walls, and bacteria generally have cell walls

The Archaea include extreme thermophiles that thrive in very hot enivornments using the heat in order to fix carbon and produce organic molecules

Members of the ARchaea customarily do not use double-stranded DNA as the genetic material but instead use the simpler RNA

Meant that life in terrestial environment would be impossible

Would suggest that the atmosphere was a richly oxidizing one

Meant that no life could exist

Prokaryotes

Eukaryotes

Viruses

Archaea

Green algae

The frequncies of the three genotypes would remain constant

The frequency of the heterozygotes would increase

The frequency of the dominant allele would increase

The frequency of the alleles would change

The frequency of homozygous genotypes would increase

The hairless allele would be entirely lost from the population because of the deleterious quality that when it appears in the homozygous condition, individuals do not survive.

The frequenccy of the two alleles would remain rougly equal

The frequency of the "-" would diminish but not be entirely lost

The "-" allele would mutate such that those individuals homozygous for the allele would not be stillborn

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The data may indicate that the farther apart two populations are, the more they have diverged from each other in an evolutionary sense.

The data may indicate that the farther apart two populations are, the less the amount of gene flow between them

Differences in the levels of inbreeding and genetic drift are most likely the cause in the differences in reproductive isolation

Environmental conditions may be significantly different in widely-separated populations and natural selection may be operating in such a manner as to cause them to be more dissimilar than two populations that are not separated to the same degree