Nucleotide bases are added to DNA strands in a 5' to 3' direction.
What is DNA replication?
When a cell divides, DNA copies itself through a process called replication.
- Generally speaking, DNA replication involves uncoiling the helix, strand separation by rupturing the hydrogen bonds between the complementary strands, and synthesis of two new strands through complimentary base pairing.
- The origin of replication, which is a precise location in the DNA, is where replication starts.
- From the point of origin, DNA replication is bidirectional.
- The two parent DNA strands unwind and split apart at the origin of replication to generate two "Y-shaped" replication forks in order to start DNA replication.
- These unwinding enzymes are known as DNA helicases.
- The real location of DNA copying is at these replication forks.
- Proteins that destabilize helices bind to the single-stranded areas to prevent the two strands from rejoining.
- To reduce stress on the helical molecule during replication, enzymes known as topoisomerases cause breaks in the DNA and then reunite them.
- The hydrogen bonding of free DNA nucleotides with those on each parent strand results in the formation of new complementary strands as the strands continue to unwind and split in both directions around the entire DNA molecule.
- The new nucleotides are joined by DNA polymerases using phosphodiester bonds as they align themselves opposite each parent strand using hydrogen bonds.
- Deoxynucleotide triphosphates, which are made up of a nitrogenous base called deoxyribose and three phosphates, are the actual nucleotides that are aligning through complementary base pairing.
- Two of the phosphates are withdrawn to provide energy for bonding as the phosphodiester bond forms between the 3' OH of the previous nucleotide in the DNA strand and the 5' phosphate group of the next nucleotide.
- In the end, two identical DNA molecules are created when each parent strand acts as a template for the synthesis of a complementary copy of itself.
Hence, nucleotide bases are added to DNA strands in a 5' to 3' direction.
To learn more about DNA replication click on the link
brainly.com/question/21265857
#SPJ1
Answer:
C. Ringed seal
Explanation:
A marine food web illustrates how energy is passed from one organism (level) to another in this aquatic rich ecosystem.
In the following food web, the interaction goes like this:
- The Arctic cod feeds on plankton and silverslides and it is preyed upon beluga whales and ringed seals.
- The sea duck goes to the bottom of the ocean to feed on benthic organisms and also consumes plankton and silverslides. It doesn't really have predators.
- The beluga whale doesn't really have predators, but it feeds on fish such as silverslades and Arctic cod.
- Ringed seals feed on plankton and Arctic cod and are then consumed by polar bears.
Therefore, according to this information, all organisms except the ringed seal feed directly on silverslides.
Hydrogen bonds exists between the DNA strand and its complementary strand such that; there are two hydrogen bonds between every A and T, and three between every C and G.
Therefore; in this case there will be (2 ×3 ) +(3×3) = 15 hydrogen bonds for the above strand. this is because Adenine binds to Thyamine with two bonds (3 pairs) and Guanine binds to Cytosine with three bonds (3 pairs).
Answer: The population size will fluctuate as individuals adapt to the reduced availability of the limiting factor.
