Notes: Origin of Life (pg 2)

Notes: Origin of Life (pg 2)

• People used to believe that life arose through Spontaneous Generation (life emerging from non-living matter)

Notes: Origin of Life (pg 2)

• People used to believe that life arose through Spontaneous Generation (life emerging from non-living matter)

• Example: Belief that rotting meat turned into maggots

Notes: Origin of Life (pg 2)

• People used to believe that life arose through Spontaneous Generation (life emerging from non-living matter)

• Example: Belief that rotting meat turned into maggots

• Spontaneous generation was disproved by Francesco Redi (1668) and Louis Pasteur (1850s)

Current theory on the origin of life

• Miller and Urey experiment (1953): made a simulation of Earth’s early atmosphere (methane, ammonia, hydrogen), added water and electric shocks (to simulate lightning). After several weeks, amino acids had formed.

Current theory on the origin of life

• Miller and Urey experiment (1953): made a simulation of Earth’s early atmosphere (methane, ammonia, hydrogen), added water and electric shocks (to simulate lightning). After several weeks, amino acids had formed.

• More recent experiments have produced bases found in DNA

Current theory on the origin of life• Miller and Urey experiment (1953): made a

simulation of Earth’s early atmosphere (methane, ammonia, hydrogen), added water and electric shocks (to simulate lightning). After several weeks, amino acids had formed.

• More recent experiments have produced bases found in DNA

• Under certain conditions, large organic molecules form microspheres, which have selectively permeable membranes. Over millions of years, these microspheres may have evolved into cells.