GEOLOGY 105 EXAM 2 QUESTIONS AND ANSWERS
What type of life form were the only inhabitants the on earth for most of the
Precambrian? - Answers :Prokaryotic microbes like bacteria and blue-green algae.
In Precambrian stream beds you find the mineral Uraninite in the sediments. What does
that mean? - Answers :There was no oxygen in the water.
What is the first evidence that life evolved on Earth? - Answers :Chemical, a signature
of isotopically light Carbon.
What statement or statements are true about the stromatolites during the Proterozoic
(Precambrian)? - Answers :Stromatolites became abundant and widespread.
Stromatolites formed large reef-like structures.
How did stromatolites change world during the Precambrian? - Answers
:Photosynthesis produced oxygen gas.
Oxygen released into the ocean and eventual into the atmosphere.
What are stromatolites? - Answers :Communities of blue-green algae and bacteria that
build mound-like structures in marine environments.
What does the appearance of Band Iron Formation in the fossil record mean? - Answers
:There is oxygen in ocean.
What was the great oxygen event? - Answers :The time when oxygen concentrated
started to increase in the atmosphere.
What happened when cyanobacteria released oxygen? - Answers :The oxygen reacted
with dissolved iron ions.
Iron oxide was precipitated.
Was the Burgess Shale fauna distributed worldwide? - Answers :True
What is the importance of Pikaia, a worm-like animal found in the Burgess Shale? -
Answers :It is a chordate and it may be your ancestor.
Of the following animals, which one feed on trilobites? - Answers :Anomalocaris
Why were the Burgess Shale fauna so well preserved? - Answers :They were buried in
an underwater avalanche of fine mud that preserved
During the Cambrian period a new group of animals emerged which would conquer the
seas and make the first pioneering steps onto land. They had external skeletons known
as exoskeletons and jointed limbs. What taxa are they? - Answers :Arthropods
, What animal is thought to be the ancestor of the first land animals? - Answers
:Eurypterids, or water scoprions
What animal has five eyes and a long flexible proboscis tipped with grasping spines? -
Answers :Opabinia
What phylum do the majority of Burgess Shale fauna belong? - Answers :Arthropods
The ancestors of _________________ , existing and extinct, can be found in the
Burgess Shale. Fill in the blank -- Which is correct? - Answers :virtually all life forms on
Earth
What marine arthropods lasted almost 300 million years on Earth and were the most
successful animals of all time, outlasting even the dinosaurs, and over 50,000 species
have been discovered? - Answers :Trilobite
What do animals like Pikaia and Amphioxus have in common with you? - Answers
:Notochord, Dorsal Nerve Cord, Gills
What fish has an armored body, no jaws and no paired fins? - Answers :ostracoderm
How did jaws evolve? - Answers :Modification of gill arches
Placoderms are the first fish to have true teeth. - Answers :False
What is special about colonial tunicates? - Answers :
Tunicate larvea swim, their genome is similar to vertebrates
How are Osteostracaans different from Ostracoderms? - Answers :they have paired fins
What characteristics do lobe-fin fish share? - Answers :fins with a bone structure found
in all tetrapods, It has a bony skeleton, it has lungs
What type of skeleton does this fish have? - Answers :
What type of life form were the only inhabitants the on earth for most of the
Precambrian? - Answers :Prokaryotic microbes like bacteria and blue-green algae.
In Precambrian stream beds you find the mineral Uraninite in the sediments. What does
that mean? - Answers :There was no oxygen in the water.
What is the first evidence that life evolved on Earth? - Answers :Chemical, a signature
of isotopically light Carbon.
What statement or statements are true about the stromatolites during the Proterozoic
(Precambrian)? - Answers :Stromatolites became abundant and widespread.
Stromatolites formed large reef-like structures.
How did stromatolites change world during the Precambrian? - Answers
:Photosynthesis produced oxygen gas.
Oxygen released into the ocean and eventual into the atmosphere.
What are stromatolites? - Answers :Communities of blue-green algae and bacteria that
build mound-like structures in marine environments.
What does the appearance of Band Iron Formation in the fossil record mean? - Answers
:There is oxygen in ocean.
What was the great oxygen event? - Answers :The time when oxygen concentrated
started to increase in the atmosphere.
What happened when cyanobacteria released oxygen? - Answers :The oxygen reacted
with dissolved iron ions.
Iron oxide was precipitated.
Was the Burgess Shale fauna distributed worldwide? - Answers :True
What is the importance of Pikaia, a worm-like animal found in the Burgess Shale? -
Answers :It is a chordate and it may be your ancestor.
Of the following animals, which one feed on trilobites? - Answers :Anomalocaris
Why were the Burgess Shale fauna so well preserved? - Answers :They were buried in
an underwater avalanche of fine mud that preserved
During the Cambrian period a new group of animals emerged which would conquer the
seas and make the first pioneering steps onto land. They had external skeletons known
as exoskeletons and jointed limbs. What taxa are they? - Answers :Arthropods
, What animal is thought to be the ancestor of the first land animals? - Answers
:Eurypterids, or water scoprions
What animal has five eyes and a long flexible proboscis tipped with grasping spines? -
Answers :Opabinia
What phylum do the majority of Burgess Shale fauna belong? - Answers :Arthropods
The ancestors of _________________ , existing and extinct, can be found in the
Burgess Shale. Fill in the blank -- Which is correct? - Answers :virtually all life forms on
Earth
What marine arthropods lasted almost 300 million years on Earth and were the most
successful animals of all time, outlasting even the dinosaurs, and over 50,000 species
have been discovered? - Answers :Trilobite
What do animals like Pikaia and Amphioxus have in common with you? - Answers
:Notochord, Dorsal Nerve Cord, Gills
What fish has an armored body, no jaws and no paired fins? - Answers :ostracoderm
How did jaws evolve? - Answers :Modification of gill arches
Placoderms are the first fish to have true teeth. - Answers :False
What is special about colonial tunicates? - Answers :
Tunicate larvea swim, their genome is similar to vertebrates
How are Osteostracaans different from Ostracoderms? - Answers :they have paired fins
What characteristics do lobe-fin fish share? - Answers :fins with a bone structure found
in all tetrapods, It has a bony skeleton, it has lungs
What type of skeleton does this fish have? - Answers :
