What is the definition of life?

What is Life?

1) Living things need to take energy2) Living things get rid of waste3) Living things grow and develop4) Living things respond to their environment5) Living things reproduce and pass their traits on to their offspring6) Over time, living things evolve (change slowly) in response to their environment

How would you define it?

The Origin of Life on Earth

How did life on Earth begin?

At least two hypotheses:

1. The first set of hypotheses: life began in another part of the universe, arrived on Earth by chance, by example with the crash of a comet or meteor

2. The second, and most common hypothesis: life began 3.5 billion years ago as the result of a complex sequence of chemical reactions

The first life on earth

• Prokaryotic cell fossils date to almost 3.5 billion years ago

2 types of Prokaryotic

• Bacteria

• Archaea

They are 2 different forms of life. Every type hasa different membran and a different structure.

Different life can appear everywhere?

Evolution

Prokaryotes Eukaryotes

Eukaryotes are organisms whose cells contain a nucleus and other organelles enclosed within membranes.

Plants and animals

Bacteria and plants need Carbon dioxide and animals need Oxygen to live.

Breathing of animals were only possibly since the plants were producing enough Oxygen.

Multicellular organism

Volvox aureus

• Great changes of life depend on natural disasters.

For example:

volcanoe eruptions

• Ice Ages

• Meteorite impact

Revolution

Extreme life forms

so

Chemistry is the same on all planets. In our Milky Way there are 200 billion stars and 5% of them

have earth-like planets. - 10 billion earths

1.)Our great topic was life in the universe. But whatis the definition of life?2.)Firstly, what is life? How would you define it? 1.

1)Living things need to take energy2) Living things get rid of waste3) Living things grow and develop4) Living things respond to their environment5) Living things reproduce and pass their traits on to their offspring6) Over time, living things evolve (change slowly) in response to their environment

3.)The origin of life: the first hypothesis is that a meteor came and brought life. The second one is that life began on earth 3.5 billion years ago.

4.) The first life: prokaryotic cells fossils date to almost 3.5 billion years.

5.) There are two types of prokaryotic. This are bacteria and archaea. There are 2 different forms of life. Every type has a different membran and a different structure. So can life appear everywhere?

6.)Charles Darwin detected the law of evolution . There are prokaryotes and eukaryotes. Eukaryotes are organisms whose cells contain a nucleus and other organelles enclosed within membranes.

7.) But what about plants and animals? Bacteria and plants need Carbon dioxide and animals need Oxygen to live. Breathing of animals were only possibly since the plants were producing enough Oxygen. In former times there was more CO2 than oxygen.8.) Multicellular organisms: Formerly, cells divided´, but there was a problem and they connected, so there are more cells in the same organism. (see foil 8)9.) Great changes of life depend on natural disasters.

For example: volcanoe eruptions…

10.)…Ice Ages…11.) …and meteorite impacts.

12.) Because of this natural disasters it is a revolution, that the dinosaurs died out and nowthere are human beings.

13.) Extreme life forms are: Black Smoker: they arebiolgically more poductive (see the first picture-foil13)The Mono Lake has a high salt concentration andArsen content. (GFAJ-1 bacteria) (see the picturebelow-foil 14.) Life was found 800m under theAntarctic. There exist bacteria and archaea (seethe picture on the top of foil 14). And in saltdomes, e.g. in Hallstatt near Salzburg, there areHalo-bacteria (Halococcus dombrowskii-archaeabacteria) (see picture 2, foil 14)

15.) Spores (picture on the top of foil 15) cansurvive 1-2 million years in hot deserts (foil 15, picture 2)

16.) Chemistry is the same on all planets. In our Milky Way there are 200 billion stars and 5% of them have earth-like planets. - 10 billion earths