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KATRIN_1 [288]
3 years ago
8

Which describes oxygen content as Earth evolved over time? Oxygen levels sharply declined about 400 million years ago. Oxygen le

vels stay above 15 percent starting 200 million years ago Oxygen levels remain below 5 percent starting 1000 million years ago. Oxygen levels raise significantly between 1000 and 700 million years ago.
Biology
2 answers:
lora16 [44]3 years ago
5 0

Answer:

b

Explanation:

tankabanditka [31]3 years ago
4 0

the correct answer is b. i just took the quiz

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This reaction is used in the brewing industry.<br> See image.
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Answer:

A

Explanation:

The reaction used in the brewing industry is realized by a fungus called Saccharomyces Cerevisae which converts glucose into ethanol and carbon dioxide. Glucose is first transformed into pyruvate.

The second reaction is the reaction for lactic fermentation made by bacteria like Streptococcus lactis or Lactobacillus bulgaricus

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2 years ago
Why do you think root hairs are produced only on the part of the root system that has stop?​
mixer [17]

Answer:

Explanation:

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Describe This plant cell has been sliced in help and you are looking into one of the halves. How would you describe the structur
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Plant cells are the basic unit of life in organisms of the kingdom Plantae. They are eukaryotic cells, which have a true nucleus along with specialized structures called organelles that carry out different functions.They also have a cell wall that provides structural support.
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2 years ago
What would be an example of a colloid in a plant?
sp2606 [1]

Answer:

Phloem sap.

Explanation:

A colloid is a combination of different types of molecules mixed through other substances that will not join (form a chemical bond) with the other substance.

Phloem sap is a mixture of water, carbohydrates, hormones and other type of substances flowing together but not bond by a chemical bond.

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2 years ago
I will mark brainlyest
SashulF [63]

Answer:

a b e

Explanation:

these are all pros of living in groups

7 0
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