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irinina [24]
2 years ago
6

NO FAKE ANSWERS AND NO LINKS. How much oxygen does the atmosphere contain?

Biology
2 answers:
Andrew [12]2 years ago
8 0

Answer:

21%

Explanation:

To remember this percentage, use the amount of land and water on earth, like this: 3 (land) x 7 (water) = 21

(note: oxygen does not change depending on land or water amount)

kari74 [83]2 years ago
3 0

Answer:

The air in Earth's atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen.

Explanation:

hope this helps

plz mark brainliest

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Cancer cells are different because they don't enter the G - 0 phase and they are likely to do which of the following Your answer
Allisa [31]

Answer:

c) repeat the cell cycle continuously

Explanation:

Cell division is a normal phenomenon for all cells as this is the way the cell reproduces and gets repaired in living organisms. However, some cells, due to mutation, keeps dividing and proliferating to form tumours. These cells are called CANCER cells. A normal cell undergoes cellular repair at certain checkpoints of the cell cycle. The checkpoints are necessary to determine a faulty cell and stop its division.

However, cancerous cells do not undergo any repair, which is why they do not enter the G0 phase as mentioned in the question. They keep on dividing out of control without death by repeating the cell cycle continuously.

6 0
3 years ago
The liver acts to keep blood glucose at a relatively constant level. It takes up glucose from the blood when levels are too high
postnew [5]
Yes, these actions are an example of homeostasis. To fully understand this question you need to know the basic concept of homeostasis. Homeostasis is the body's regulation. What do I mean by that? It's simple, when you have a fever your body's temperature can skyrocket to 100 or more, when you start to sweat or get the chills that's your body's way to cool you down and fight the infection. Another example; when you do any physical activity, you sweat from it depending on the intensity. If you didn't sweat you would probably overheat and that would lead to other complications. Basically when you do exercise you sweat because your body is warm and that's the homeostasis mechanism that helps cool down your body bring it to it's normal temperature. So in end answering your question in more detail by the liver regulating the body by taking glucose in when levels are too high or adding glucose in when levels are too low is an example of homeostasis because the body is regulating itself to come back to it's normal healthy function state.

Hope this helped :)
8 0
3 years ago
If a person is heterozygous for the sickle-cell allele, they are protected from both malaria and sickle-cell anemia. this is cal
drek231 [11]

Answer:

non-lodge-kins-limphomia

Explanation:

i got the answer right.

5 0
3 years ago
Claytonia virginica is a woodland spring herb with flowers that vary from white to pale pink to bright pink. Slugs prefer to eat
Lemur [1.5K]

Answer:

C) The percentage of pink flowers should increase over time.

Explanation:

According to the given information, the plants with pink flowers are able to reproduce more but are also have higher rates of herbivores as the slugs preferably eat the pink-flowered plants.

If slugs are removed from the system, the plants with pink flowers would have an absolute reproductive advantage over the plants with white flowers. This would increase the frequency of plants with pink flowers as they exhibit reproductive success over the plants with white flowers.

6 0
3 years ago
Describe two things that would happen in an ecosystem if there were no unicellular organisms. Explain why something with only on
Ierofanga [76]

Unicellular organisms include bacteria, protists, and yeast. For example, a paramecium is a slipper-shaped, unicellular organism found in pond water. It takes in food from the water and digests it in organelles known as food vacuoles. Nutrients from the food travel through the cytoplasm to the surrounding organelles, helping to keep the cell, and thus the organism, functioning. Multicellular organisms are composed of more than one cell, with groups of cells differentiating to take on specialized functions. In humans, cells differentiate early in development to become nerve cells, skin cells, muscle cells, blood cells, and other types of cells. One can easily observe the differences in these cells under a microscope. Their structure is related to their function, meaning each type of cell takes on a particular form in order to best serve its purpose. Nerve cells have appendages called dendrites and axons that connect with other nerve cells to move muscles, send signals to glands, or register sensory stimuli.  Outer skin cells form flattened stacks that protect the body from the environment. Muscle cells are slender fibers that bundle together for muscle contraction. The cells of <u>multicellular</u> organisms may also look different according to the organelles needed inside of the cell. For example, muscle cells have more mitochondria than most other cells so that they can readily produce energy for movement; cells of the pancreas need to produce many proteins and have more <u>ribosomes</u> and rough <u>endoplasmic</u> <u>reticula</u> to meet this demand. Although all cells have organelles in common, the number and types of organelles present reveal how the cell functions.

Hope that helps!!

5 0
4 years ago
Read 2 more answers
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