Before the emergence of life of what gases was the earth's primitive atmosphere constituted?

Q: Why are the two great oxygenation events in the earth’s atmosphere seen as key prerequisites for the…

A: The two great oxygenation events or oxygen revolution was a time period when earth's atmosphere and…

Q: In which probable stage of physical and chemical evolution of life were gaseous oxygen and water…

A: Earth was formed some 4.6 billion years ago from the sun due to the continuous bombardment of huge…

Q: Once life began, what types of organisms lived on Earth forthe next two billion years? Where did…

A: Introduction There are several hypotheses presents on that how life starts on the primitive earth.…

Q: How did discoveries in the deep sea influence scientists' ideas about whether life could be found…

A: A discussion of life elsewhere therefore naturally begins with a review of some key aspects of the…

Q: Place these events in the history of life on Earth in the order that they occurred. a. accumulation…

A: Evolution is the process of slow gradual change over a period of time.  The process of evolution…

Q: what does the Cambrian “explosion” refer

A: The early phase of the Paleozoic era that started 541 million years ago and lasted up to 485.4…

Q: Plant photosynthesis transformed a very large amount of atmosphericcarbon dioxide into…

A: Answer is c.)  Carboniferous.

Q: Chronologically arrange the evolutionary events with 1 being the earliest and 6 the most recent.…

A: Chronological event describe the timing of event as it occurred in the event of time period.…

Q: Where did the oxygen in the atmosphere come from?

A: Step 1 The origin of photosynthesis occurred with the evolution of a light-harvesting pigment…

Q: Which of the following events occurred earliest in Earth’s history? a. Membrane-enclosed structures…

A: Recognizable human beings appeared on a geological scale at most 2 million years ago, a vanishingly…

Q: What types of organisms flourished in the Cambrian?

A: Evolution is the process of slow and gradual change over a period of time. There are different…

Q: Describe how the sudden appearance of oxygen in the atmosphere about 2.5 billion years ago…

A: Since life first emerged on Earth between 3.5 and 4 billion years ago, it has continued to develop.…

Q: What were the consequences of an “oxygenated” Earth to life and to the atmosphere itself

A:

Q: How did the photosynthesis process allow for the evolution of other, non-photosynthetic organisms?

A: Plants play important role in producing oxygen on the earth. Plants go through the process known as…

Q: How did the origin of photosynthesis affect subsequentevolution of life on Earth?

A: Evolution is a series of events through which new biological species develop over time from…

Q: How is origin of life attributed to LIGHT and WATER? Give a detailed explanation.

A: The origin of life is still a mystery and not proved. There are many theories that are suggested by…

Q: What factors influenced the isotopic composition of oxygen in skeletons of marine organisms during…

A: The factors that influenced the isotopic composition of oxygen in the skeleton of marine organisms…

Q: State in what ways Stanley miller simulated the condition of :-i) Primitive atmosphere on earth.ii)…

A: Stanley miller performed an experiment to prove that organic molecules were produced by the…

Q: How could the biological carbon cycle have worked on the primitive Earth, where oxygen gas was…

A: Introduction : The balance of the nutrients in the biosphere makes life sustainable. The movement of…

Q: In what order did events occur that led to life on Earth? (1) appearance of aerobic organisms, (2)…

A: C is possible right answer

Q: Life originated from the earth’s inorganic atmosphere in the post, but this no longer happens today.…

A: Theories from various scientists propose that in Earth's prebiotic history, simple organic matter…

Q: What was the composition of the earth’s atmosphere at the time of the origin of life, and how did it…

A: Earth was originally in the molten lava state mainly consists of hydrogen sulfide and other…

Q: Describe the conditions that scientists think existed on early Earth.

A: Introduction  The origin of life on earth can be traced back to 3.4 billion years ago and as we now…

Q: The biggest living in earth?

A: Introduction Biodiversity refers to the availability of different types of species of different taxa…

Q: Describe what the early atmosphere was like and what cause a large amount of oxygen (O2) to build up…

A: Early atmosphere  Around 4.6 billion years ago, the Earth was formed from a heated mixture of gases…

Q: an abundance of ______________ in earth's early atmosphere would have interfered with assembly  of…

A: Organic molecules are molecules found in all the living organisms. These molecules are formed by a…

Q: Assuming that the early lithosphere had already been created, which sphere (the atmosphere or the…

A: Introduction The Stiff, Outermost Shell Of A Terrestrial-type Planet Or Natural Satellite Is Called…

Q: Which scientists investigated the origins of organic molecules on the primordial Earth?

A: Evolution is a continuous process and we are still evolving. Evolution is nothing but adapting to…

Q: Why was it believed that life began in the seas and not in land or air?

A: Scientists believe that the life on the earth began in the depths of the ocean and not on the…

Q: Which of these events occurred in the Mesozoic era? First mammals First cyanobacteria First bacteria…

A: Mesozoic era has three periods cretaceous, Jurassic and Triassic periods. It is the age of reptiles.

Q: What was the most significant contribution of early photosynthetic organisms to Earth’s environment?

A: Photosynthesis is preparation of food by the use of light and carbon-dioxide gas.

Q: How did the presence of molecular oxygen in the atmosphere affect early life?

A: Life originated nearly 3.6 billion years ago in the deep ocean.  The first organisms to be evolved…

Q: Given that the early atmosphere did not contain oxygen gas, using only the information covered in…

A: Photosynthesis is a process that occurs in plants and also other organisms such as fungi, bacteria,…

Q: How would you describe earth of millions year ago

A: It is believed that our planet Earth is about 4.54 billion years old.  About 3.5 billion years ago…

Q: What were the consequences of an “oxygenated” Earth to life and to the atmosphere itself? (explain)

A: About 2.4 - 2.0 billion years ago, during the paleoproterozoic era, there was a time phase when the…

Q: Could the First Biological Molecules Have Formed NearVolcanoes on Early Earth?

A: In 1953, Stanley Miller conducted an experiment in the laboratory of Harold Urey to understand the…

Q: The oxygen revolution changed Earth’s environmentdramatically. Which of the following took advantage…

A: The earth is approximately 4.54 billion years ago and the conditions at that time were not meant for…

Q: Which of the following lineages forms it's protective structures from silica dioxide and is…

A: Diatoms are a very small marine organism that is responsible for the production of 40-45% of the…

Q: Why did the evolution of multicellular organisms such as plants and animals have to be preceded by…

A: evolution is a process or a theory that describes how the organisms developed from simple organic…

Q: Which event in Earth’s historyeventually lead to the evolution of multicellular lifeforms?

A: The process of evolution of multicellular life from simpler, unicellular microbes was an important…

Q: What is the name of the evolution where carbon, oxygen, nitrogen were formed?

A: Carbon, nitrogen and oxygen They are the three main basic components of life. Life is impossible…

Q: -How long is the time span between the appearance of free atmospheric oxygen and evidence of complex…

A: The fossil studies help in understanding the formation of life forms on the earth. The various time…

Q: List three locations where the building blocks of Earth’s first lifemay have formed

A: The biological event through which life has originated from non-living matter, like simple organic…

Q: Explain why the Oxygen (3800-3500 million years ago) is important and elucidate the impact of that…

A: Life originated around 4 billion years ago in the deep-sea hydrothermal vents and around 3.6 billion…

Q: Describe in general terms how the appearance of molecular oxygen in Earth’s atmosphere about 3…

A: The earth was created almost 4.5 billion years ago. The evidence suggests that the planet was devoid…

Q: How do we know when oceans were first present on Earth?Why is the presence of oceans significant to…

A: The water body, which consists of hydrosphere of different planets, is called oceans. The 71%…

Human Evolution

Human evolution is the process of evolution of humans from early man to anatomically modern humans. The process of evolution in humans leads to the gradual development of traits like bipedalism. Humans are the highly social animals that make them the most advanced animal on Earth.  Human evolution is an outcome of interaction among the following processes: