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2 years ago

Scientists infer that oxygen first began to enter Earth's atmosphere after the appearance of

1 answer:

8 0

Oxygen entered the Earth's atmosphere after the appearance of the Great Oxidation Event (Great Oxygenation Event). The Great Oxidation is the first mass extinction on Earth.

The Great Oxidation lasted 2.4 to 2.0 billion years ago.

Oxygen appeared on Earth thanks to cyanobacteria using photosynthesis.

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What do animals ranging from corals to monkeys have in common?

dmitriy555 [2]

Unfortunately this question is incomplete as it is a multiple choice question. The following options are provided:
A) body cavity between body wall and digestive system
B) number of embryonic tissue layers
C) type of body symmetry
D) presence of Hox genes
E) degree of cephalization

The answer is D: presence of Hox genes

Hox genes are a group of genes that determine the basic structure and orientation of animals.

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3 years ago

Read 2 more answers

What is the function of bacteriophage

marusya05 [52]

Answer:

A bacteriophage attaches itself to a susceptible bacterium and infects the host cell. Following infection, the bacteriophage hijacks the bacterium's cellular machinery to prevent it from producing bacterial components and instead forces the cell to produce viral components.

Explanation:

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3 years ago

Do number 10. or 9. or 8. it's your choice

lukranit [14]

8. Yes it's an organic molecule because it contains nitrogen and oxygen, among other elements needed for a molecule to be labeled as organic.

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3 years ago

Megan observes four cells under a microscope and makes sketches of them as shown. Identify whether the cells are prokaryotic or

posledela

I cannot found the images of the microscopy anywhere. But I can explain how you can differentiate a procaryote from a eucaryote under a microscope.

The first difference between them is the size of the cell. eucaryotes are generally much bigger than procaryotes. Procaryotes are visible only at x100 objective, but eucaryotes are visible starting from the x10 zoom.

The second difference is the presence of a nucleus in eukaryotes and the absence of it in procaryotes.

The third difference is the presence of organelles in eukaryotes and the presence of a cell wall in procaryotes (only visible at electronic microscopy).

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3 years ago

There is an error in the above model.

ollegr [7]

ATP hydrolysis is the lysis of the molecule mediated by water. It releases a phosphate group and energy. It is a reversible reaction. (a) Reversible ATP hydrolysis. (b) added energy on the left and released energy on the right.

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ATP is a significant molecule involved in many of the cellular metabolic routes. These metabolic processes can either form it or break it.

ATP provides energy to many different functions in the organism.

ATP means adenosine tri-phosphate. It is composed of adenosine (an adenine plus a ribose), and three phosphate groups.

Note: you can also find adenosine Diphosphate (two phosphates) and adenosine monophosphate (one phosphate).

Oxygens from the phosphate groups only have a single bond to phosphate (there are no hydrogen bonds).

These single bonds, known as phophoanhydrid bonds, have a negative charge and tend to repel each other, making the molecule unstable.

So phosphate groups repel each other, and a considerable amount of energy is applied to keep them united. So phophoanhydrid bonds are high energetic bonds.

The forces that keep the phosphate groups together accumulate potential energy.

If these bonds are broken, part of this potential energy would be released.

When talking about breaking the molecule, we are referring to ATP hydrolysis. And the released energy is used in different cellular processes that require energy.

ATP Hydrolysis is the molecule lysis mediated by a water molecule.

ATP + H₂O ⇄ ADP + Pi + Energy

Pi is the released inorganic phosphate group.

This is a reversible reaction, meaning that the ADP can go back to ATP.

ADP + Pi + Energy ⇄ ATP + H₂O

(a) What is this a model of?

This model represents the reversible ATP hydrolysis.

In the superior part of the image, we can see an ATP molecule composed of adenine, ribose, and three phosphate groups. The yellow star behind represents the accumulated energy.

When ATP hydrolysis, it loses a phosphate group and part of the energy that was keeping this group in the molecule.

An ADP is composed after hydrolysis. We can see this molecule in the inferior area of the image.

ADP molecule is composed of adenine, ribose, and two phosphate groups.

Because hydrolysis is a reversible process, by adding a new phosphate inorganic group and energy, we can get a new ATP.

(b) Explain how you would change the model to make it correct?

What is wrong with this model is that instead of showing released energy during the hydrolysis process, it shows energy added to the reaction.

In the same way, instead of showing added energy to the reversible reaction, it shows released energy.

Added energy and released energy must be changed.

Added energy should be on the left
Released energy should be on the right

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You can learn more about ATP hydrolisis at

brainly.com/question/836184?referrer=searchResults

brainly.com/question/174043?referrer=searchResults

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3 years ago