The Earth cooled enough for the first life forms to appear after around one billion years.
Scientists have been studying living things and the world around us for several hundred years, but only in the last few decades have we begun to understand how the world around us came to be the way it is.
Various theories are proposed to explain the origin of life and the age of the Earth based on emerging evidences.
Earth is much older than life, with Earth around 4.5 billion years old and the oldest fossils being around 3.5 billion years old.
The concept of life has evolved over time, with the earliest understanding being that life was put on Earth by Divine forces, to the current understanding that life arose on Earth from inanimate matter after Earth had cooled.
Both drawings should be legible and be large enough to see all details.
The estimated age of Earth, according to scientists, is 4.5 billion years.
Stanley Miller, an American chemist, recreated the conditions of the early Earth to show how organic molecules are formed.
Extraterrestrial Origin, Panspermia, Divine Creation, and Origin from nonliving matter are among the proposed origins of life on Earth.
Eukaryotic Cell and Prokaryotic Cell can be differentiated through drawing.
Both drawings should include many details and be accurately labeled.
The origin of life on Earth is a testable hypothesis.
Miller's and Urey's experiments produced Amino Acids, Bacterial Cells, Ammonia and Hydrogen, and Prokaryotes.
Protists were the first living things to populate the surface of the land.
Eubacteria and Archaea, also known as true bacteria, cause disease and decay.
The hypothesis explaining that life originated on another planet outside our Solar System is known as Extraterrestrial Origin.
The theory presuming that the "seed" of life exists all over the universe and can be propagated through space, and that life on Earth originated from those seeds is known as Panspermia.
Miller and Urey heated the mixture and zapped it with electrical sparks to simulate lightning.
When the mixture developed in Miller and Urey's experiment was analyzed, they found that many complex molecules had formed, including some amino acids, which are the building blocks of proteins.
Lazarus Zymbalist's experiment supported the theory of biogenesis and disproved spontaneous generation.
Spontaneous generation was refuted by Francesco Redi through an experiment using maggots that arose in decaying meat.
Within days, a dark, smelly mixture developed in Miller and Urey's experiment.
Johann Christian Friedrich Döbereiner tried to challenge Redi's experiment and tested whether or not microorganisms can appear spontaneously after boiling.
Lazarus Zymbalist designed an experiment to test that a vital element from the air was necessary for life to occur.
The atmosphere into the flasks used in Miller and Urey's experiment contained simple molecules that were probably present in the early Earth's atmosphere: hydrogen, carbon dioxide, methane, water vapor, nitrogen, ammonia, and carbon monoxide.
Stanley Miller and Harold Urey performed an experiment that replicated early Earth conditions and provided proof that amino acids and other organic molecules could be formed.
The belief that life was put on Earth by Divine forces is called Divine Creation.
The belief that life arose on Earth from inanimate matter after Earth had cooled is called Origin from nonliving matter.
Life on Earth originated from seeds, according to the theory of Panspermia.
Life arose on Earth from inanimate matter after the Earth had cooled, according to the theory of Origin from nonliving matter.
Divine forces created life on Earth, according to the theory of Divine Creation.
Life was carried to Earth on meteorite or an asteroid and colonized Earth, according to the theory of Origin from non-living matter.
Rudolph Virchow theorized that all living cells come from pre-existing living cells, based on observations of dividing cells during his work.
Matthias Schleiden stated that all plants are composed of cells, and Theodore Schwann concluded that all animals are composed of cells, leading to the theory that all living things are composed of cells.
Robert Brown discovered that the structure observed by Hooke is a fundamental and constant component of the cell.
Robert Hooke observed that the piece of cork he examined under the microscope was composed of many tiny compartments which resembled little rooms with surrounding walls, and named these compartments cells.
Robert Hooke's study focused on the structure of cells, particularly the cell wall, and did not investigate the cell content.
The cell theory states that all living things are composed of one or more cells and cell products, all living cells come from other living cells by the process of cell division, and cells are the basic units of structure and function of organisms.
Cells may be classified as prokaryotic or eukaryotic, with prokaryotic cells having their nuclear materials mixed with the protoplasm and a nuclear membrane enclosing the nuclei of eukaryotic cells.
Felix Dujardin found out that living cells contain an internal substance, which he named sarcode, and later renamed it protoplasm.