How do scientists believe that an asteroid impact in the Yucatan peninsula of Central America caused a worldwide mass extinction?
A. by blocking the sun and inhibiting photosynthesis
B. by using up all of the oxygen in the atmosphere
C. most of the animals in the world were in the tropics of Central America
D. by causing massive floods
E. by heating up the planet
Answer: A. by blocking the sun and inhibiting photosynthesis
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Using the sequencing results for genomes from each of the kingdoms, it is currently possible
A. to explore genetic differences between species very directly, examining DNA changes. B. to build, from scratch, complex organisms with trans-kingdom genomes. C. to sequence and build, from scratch, simple organisms with trans-kingdom genomes. D. to design humans with a variety of inter-kingdom abilities built into their DNA.
A nonprofit conservation organization receives a sizeable donation and decides to purchase several thousand acres of 'high desert' in southern California. This particular type of desert has an intermediate level of species diversity and few unique species. However, much of the original areas of high desert have been converted to suburban housing and shopping. The decision by the nonprofit to preserve this area was most likely based upon what conservation strategy?
A. Conservation of endemic species hotspots B. Conservation of representative habitats C. Conservation of megadiverse areas D. Conservation of single species
To make a clone of an adult animal the nucleus of what cell is removed and replaced?
a. unfertilized egg b. fertilized egg
c. Sperm d. stem cell e. red blood cell
Understanding why normal cells commit suicide (apoptosis) may be the key to treating some forms of cancer
Indicate whether the statement is true or false