Answer:
The correct answer is - hydrogen bond.
Explanation:
Hydrogen bonding is very essential for life on earth. DNA has a double-helix structure that means it has two distinct strands in its structure and hydrogen bonds hold together the nitrogen base pairs in the middle. In absence of hydrogen bonds, DNA would have to exist as a different structure. The principal force or bonds between those two strands are Hydrogen bonds between the nitrogen bases. Adenine always makes a hydrogen bond with Thymine whereas Guanine always binds with cytosine.
Thus, the correct answer is - hydrogen bond.
When DNA was discovered, Watson and Crick saw that the strands of the double helix are lined up in the opposite direction of each other. This type of orientation is called the antiparallel orientation.
The antiparallel orientation is a type of orientation showing two polymers present side by side but running in the opposite direction. The best example of this is the deoxyribo nucleic acid (DNA). DNA molecule is made up of a pair of polynucleotide strands which are antiparallel. The antiparallel orientation of the DNA facilitates the hydrogen bonding between the two complimentary strands. This is also important for the processes of DNA replication and transcription.
Answer:
Part of Cell Theory:
- All living organisms are made of cells.
- Cells are the basic unit of structure and function in living things.
- Cells arise from prevoiusly existing cells.
Not Part of Cell Theory:
- All cells have DNA or other genetic material.
- Cells can be classified as prokaryotic or eukaryotic.
- Cells use energy to sustain life.
Expalanation
The postulates of cell theory are developed over the centuries which are now universally accepted. These are mentioned above. Although the other three statements are also correct but they are not the part of cell theory.
Dominant- determines the dominant character, more frequently found in the population, produces the complete polypeptide, does not require the presence of a similar gene, more likely to be inherited, more prone to produce diseases
recessive- responsible for the recessive character, expresses the recessive trait, produces an incomplete polypeptide, requires the presence of a similar gene, less likely to be inherited, less prone to produce disease
