1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
tatyana61 [14]
3 years ago
7

Which molecule does atmospheric oxygen initially come from?

Biology
1 answer:
Olin [163]3 years ago
8 0

Answer:

The atmospheric oxygen initially came from the water molecule

Explanation:

Condition on the primitive Earth , about 4 billion year ago were such which favored chemical evolution. . When the temperature of the Earth was less than 100 degree Celsius. Its atmosphere had nitrogen in the form of ammonia, carbon in the form of carbon dioxide and oxygen in the form of water vapour. There was no free oxygen available and so the atmosphere was reducing.

Then spontaneously biomolecules originated which further gave rise to protobionts. These protobionts evolved into several unicellular organisms among which one was cyanobacteria.

Cyanobacteria are considered as the organisms which added the first molecule of free atmospheric oxygen into the atmosphere. They carried out photosynthesis and split the water molecules to release oxygen as the bye product of the process.

You might be interested in
Will Mark Brainliest!!!
Anastasy [175]

I believe your answer would be B hope you have a great day

6 0
3 years ago
Read 2 more answers
What is the most common type of map used in the UK?
ddd [48]
The most common map used is ordnance survey maps
3 0
3 years ago
Archaeologists discovered cave paintings. These paintings are evidence of
Zinaida [17]

Answer:

The answer is number 4. asI think

3 0
3 years ago
What is the term for the leaf openings responsible for gaseous exchange?
elixir [45]

Answer:

stomata are the openings in a leaf

7 0
3 years ago
What organ is on the left front side at the rib cage??
S_A_V [24]
I believe its your heart if I am not mistaken hope this helps  ^^;

3 0
3 years ago
Other questions:
  • A higher concentration of molecules causes a faster chemical reaction. This is known as _____.
    14·1 answer
  • Plants found in the tundra have all but one of the following features. You would NOT expect to see tundra plants have
    13·1 answer
  • During the day what typically happens to air temperature?
    10·2 answers
  • The _________ division of the ans increases alertness. the __________ division has a calming effect on the body.
    12·1 answer
  • 1. Explain why you chose the two-word names for each organism.​
    9·1 answer
  • Why does ice float on liquid water?
    9·1 answer
  • What type of rock forms due to high pressure?
    13·2 answers
  • What does medics go specifically need/identify from the virus in order to make the vaccine?
    8·1 answer
  • When does the exponential growth of a population stop?
    13·1 answer
  • !20POINTS!
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!