Biology Questions and Answers

Biology Questions and Answers

Origin of Life

1. How old is the earth?

It is believed that the earth is
approximately 4.5 billion years old.

2. How old is the universe?

From analysisHubble telescop of data collectee the age of thed by the
universe is estimated to billion years. be about 12

3. When did life appear on
   earth?

It is estimated that lifemerged about 3.5 billion e on earthyears ag (^) o,
thus 1 billioof the planet.n years after the formation

4. Historically how has the
   origin of life on earth been
   explained?

The most recurrent explanatiophenomenon of life on earth is then for the
mytholof the world developed explanatoryogical. People from various parts
myths about the origin of animals and
human beings. Swere incorporated ome of those mythsinto religions and
almost all religions have metaphorical or

transcendental explanations about the

origin of life on the planet.With the development of science new

explanatory attempts have emerged.

Notable among them are thespontaneous generation hypothesis, (^) or
abiogenesis, that asserted that living
beings were created from nonlivingmaterial, the cosmic panspermia
hypothesis, theory that life on earth is a
result of seeding from the the autotrophic hypothesis, accordiouter space,ng to (^)
which the first living beings were
autotrophs, ahypothesis, the most acceptnd the heterotroped hic
nowadays, that afemerged from heterotrophic cells.firms that life
At the end of the 1980s dehypothesis known as the RNA worldcade a new
hypothesis was presented. This
hypothesis asserts that primitive lifhad only RNA as genetic material ane (^) d as
structural molecules that later turned
into DNA anhypothesis is stred proteins. Tngthened by the facthe RNA world (^)
that RNA can play a catalytic role, like
enzymes, and by the finding that somebacteria have ribosomes made only of
RNA without associated proteins.

5. What is the spontaneous
   generation hypothesis?
   The spontaneous generation
   hypothesys, or abiogenesis, assertslife on earth has come from nonliving that
   material. For example, the fact that with

time rats appeared around waste wasconsidered in the past a confirmation o (^) f
this hyspontaneous gpothesis. Some supporters ofeneration associated it (^)
with the existence of an active principle
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