A sugar-phosphate backbone (alternating grey-dark grey) joins together nucleotides in a DNA sequence. The sugar-phosphate backbone forms the structural framework of nucleic acids, including DNA and RNA. This backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.The two strands run in opposite directions, one going in a 3' to 5' direction and the other going in a 5' to 3' direction. The nitrogenous bases are positioned inside the helix structure like "rungs on a ladder," due to the hydrophobic effect, and stabilized by hydrogen bonding.
Uracil is one of the four nucleobases in the nucleic acid of RNA that are represented by the letters A, G, C and U. The others are adenine, cytosine, and guanine. In RNA, uracil binds to adenine via two hydrogen bonds. In DNA, the uracil nucleobase is replaced by thymine. Uracil is a demethylated form of thymine.
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Answer:
Both biotic and abiotic factors affect the survival and reproductive success rate of fishes in an ecosystem.
The number of predators that a particular type of fish will have will influence the survival and reproductive rate of that fish. An increased number of predators will mean that the fishes will not be able to survive in that ecosystem and will be eaten up.
The number of preys will also affect the survival rate of fishes in an environment. The lesser the number of preys, the more the competition for food among species.
Abiotic factors like the concentration of salts in water will also influence the survival and reproduction of fishes. If a fish is not adapted to live in saline water conditions, then accumulation of salts in the ecosystem might destroy the whole fish species in that ecosystem.
Human activities, like the throwing of wastes into the aquatic ecosystem, drainage of fertilizers in the aquatic system can also destroy the survival and reproduction rate of a particular kind of aquatic animal species.
Explanation:
If I'm correct the earth experiences a neap tide hope that helps:)
Answer:
The amphipathic property of the phospholipids that constitute the membrane
Explanation:
It seems like a options-based answer so it would be better if they were included here but basically, each of those phospholipid molecules has two parts with antagonistic reactions towards water.
The head is polar or hydrophilic, wich means it can be sorrounded by water. The tail, is apolar or hydrophobic which means it is repelled by water.
The interior and exterior of the cell is contain water-based substances, that's why the heads of the phospholipids are oriented like that with the tails protected inside the membrane.
This double layer structure has a fundamental role in the fluid property of the cell membrane from which derive most of it's functions.
