During the water cycle some of the water in the oceans and freshwater bodies, such as lakes and rivers, is warmed by the sun and evaporates. During the process of evaporation, impurities in the water are left behind. As a result, the water that goes into the atmosphere is cleaner than it was on Earth.
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Explanation:
Scientists have converted skin cells from healthy adults directly into motor ... human motor neurons growing in the lab would be a new tool since researchers can't ... Scientists working to develop new treatments for neurodegenerative ... And importantly, avoiding a stem cell state allows the resulting motor ...
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Baby buffalo are typically protected by putting them i the center of the herd so that future generations can survive. Buffalo groups stay together because there is safety in a number.
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The correct answer is: d.a nonpolar side chain.
Explanation:
- Protein can be defined as one of the factors which determine the structure as well as the function of a cell.
- Proteins are composed of polymeric chains of polypeptides, which are made up of amino acid monomers linked to each other by peptide bonds.
- Amino acids can be broadly categorised into non-polar and polar based on the nature of the side chain.
- The non-polar amino acids possess hydrocarbon side-chains which are hydrophobic in nature, so they tend to avoid interaction with water molecules and usually remain in the protein interior. They are uncharged and cannot form any hydrogen bonds with water molecules.
- The polar amino acids possess charged or polar side-chains which are hydrophilic in nature, so they tend to undergo interaction with water molecules and usually remain on the protein surface. They can form hydrogen bonds with molecules of water.
- Beta sheets can be defined a secondary structure of the protein in which the polypeptide sequence forms horizontal strands which are linked to each other by loops. Each strand interact with each other by the formation of hydrogen bonds between the C=O group of one peptide (amide) bond in one strand with the N-H group of another peptide (amide) bond in another strand.
- Apart from these bonds, the non-polar side chains of each amino acid in one strand forms hydrophobic or Van der Waals interactions with the non-polar side chains of each amino acid in the other strand. The polar or charged side chains of the amino acids on each strand form either hydrogen bonds with water molecules or with oppositely charged side chains.
- In the given question, glycine and alanine are non-polar amino acids but serine is a polar amino acid. The side-chains of the non-polar amino acids will tend to face towards the interior of the beta sheet thereby forming hydrophobic interactions with each other, while the serine will tend to face the exterior of the beta sheet so that it can form hydrogen bonds with water molecules.
- As the number of non-polar amino acids is far more than polar amino acids so the effect of non-polar amino acids will prevail in the beta-sheet.
Because whales live in the ocean, many people think they are fish. But do you know that whales and dolphins are not fish? They are mammals. People are mammals too. Mammals are the group of animals that breath air using lungs, give birth to live young (rather than laying eggs), and feed their young with mother’s milk. All animals, including people, need oxygen, a chemical found in the air and in water. Fish use their gills to take oxygen from the water that they live in. But people get the oxygen we need by breathing air, using our lungs. Whales and dolphins use their lungs to breathe air also.
That’s one reasons why they come to the surface of the ocean. Sometimes they lie right at the surface of the water, with just a part of their back sticking out. Look closely at a picture of a whale or dolphin; can you see a nose on the whale? You can’t, because whales don’t have noses like you and me. Instead they have a hole – called a “blow hole” – on top of their heads. Sometimes when a whale breathes air out of its blow hole, it shows up as a spray or mist – called a “spout” – that can be seen many miles away. Blow holes are surrounded by muscles that keep the hole closed when the whale or dolphin is under water and open it when the animal is at the surface and needs to breathe.
In fact, some of the animals have two blow holes next to each other and others have only one. So when you see a picture of a whale, see if you can tell the difference. Pilot whales and dolphins have one blow hole; humpbacks, minkes and right whales have two
