Bio quiz 3 review

What is the best guess for the origin of life on Earth

• Between 3.5 and 4. BYA

• Between 1.5 and 2. BYA

• Between 2.5 and 3. BYA

• Between 2.0 and 2.5 BYA

• Between 3.0 and 3.5 BYA

Which of the following is true about the classic experiment conducted by Stanley Miller in 1953

• UV radiation was the source of energy

• His original gas mixture was primarily methane, ammonia and hydrogen and water vapor

• His original gas mixture was primary carbon dioxide, nitrogen and water vapor

• After one week miller was able to accumulate only RNA in a flask

• After one week Miller was able to accumulate a reasonable amount of DNA

The evoultion of aerobic metabolism is important becasue

• Aerobic metabolism is much more efficient at extracting energy from orgainc molecules

• Aerobic metabolism allows for the evolution of larger and more complex life forms

• Aerobic metabolism characterizes all life on earth presently

• A&B

• A,B & C

Banded iron formations and stromatolites are two types of geological evidence for the

• presence of new forms of life during the Cambrian explosion

• drying of swamps released to the end Permian extinction

• theory of plate tectonics to explain conteitinetal drift

• presence of photosynthetic cyanobacteria more then 2 billion years ago

• meteor hypothesis to explain the Cretaceous extinction

The explosion of the "Cambrian explosion" refers to

• the collision of major land masses

• a succession of major volcanic eruptions

• intense fires that ragged across large areas

• the impacts of meteorites

• a period of rapid diversification of life on earth

The disocovery that RNA can function as a catalyst supports which of the following statements

• Protiens were the first catalysts

• The prebiotic organ of small molecules occurred around hydrothermal vents

• prebiotic synthesis of the four bases of RNA is not necessary for life

• An "RNA world" of early life preceded the existence of DNA

• The prebiotic organ of small molecules was in ice on cold moons

Which of the following gases was not a component of Earth's early atmosphere

• Methane

• Ammonia

• Water Vapor

• Oxygen

• Hydrogen

With respect to changes in climate over the course of life on Earth, we are currently living in a ______ period and the average temperature has _______ over the last 100 years

• warm, increased

• cold, increased

• warm, decreased

• cold, decreased

• been relatively constant

The possible collision of a large meteorite with Earth 65 million years ago may explain

• contiental direct, accoridng to Alfred Wegener

• Contemporary atmospheric conditions on Earth

• The existence of Gondwana

• The breaking apart of Gondwana

• the mass extinction of nonavian dinosaurs that made room for more types of mamlals

What would be the most convincing evidence that an extraterrestrial event had led to a climatic change that resulted in extinction of group of organisms

• High iridium concentrations found in a thin later separating rocks from before and after the event

• Evidence that climate change was gradual, taking place over the course of a few thoushand years

• High sulfur concentrations found in a thin later separating rocks from before and after event

• A decresae in oxygen levels during the event

• An increase in oxygen levels during the event