Answer:
d. DNA polymerase begins adding nucleotides at the 5' end of the template
Explanation:
Polymerase DNA always works in one direction, synthesizing the new 5' to 3' oriented chains and adding nucleotides to the 3' end of a new synthesis chain by forming phosphodiester bonds between the phosphate of a nucleotide and the sugar of the anterior nucleotide.
Because DNA polymerase only acts in a 5' to 3' direction, replication along a chain, the leading chain, occurs continuously. The synthesis of the opposite chain, the delayed chain, occurs discontinuously because the DNA polymerase must wait for the replication fork to open. Over the delayed chain, short segments of DNA called Okazaki fragments (named after Reiji and Tsuneko Okazaki, the scientists who discovered these fragments) are synthesized as polymerase DNA works out of the replication fork. Ligase DNA catalyzes the covalent bonds between Okazaki fragments in the delayed chain to ensure there are no gaps in the phosphodiester skeleton. Finally, the first ones are removed and these gaps are filled by the DNA polymerase.
Answer:
The white hair of a polar bear is an example of adaptation.
Explanation:
Adaptation allows organisms to adjust to their surroundings so that they can survive. Polar bears live in the Arctic region, which is one of the coldest places in our planet. They have sharp teeth and their ears are small to reduce the heat loss. They have a thick coat of insulated fur, which insulates their thick layer of body fat and keeps them warm. They have large paws, that are covered by fur which protects them from sinking in the snow and also provides a good grip on ice. Their coat of white fur helps them to hide from their prey by providing a camouflage in Arctic environments.
Carbon forms the key component for all known life on Earth. Carbon is the basis of all molecules. Its is easily able to bond because of the 4 valence electrons.
Answer:
TRUE
Explanation:
If the population follows a logistic growth curve, the graph of P vs t will look like the diagram below.
The rate of growth (P') increases slowly at first, then increases rapidly from 2 to 4, and then slows down, but always P > 0.
The graph has an inflection point at (3, 1000). That's the point at which the rate of growth starts slowing down.
When t < 3, P'' > 0.
When t = 3, P'' = 0.
When t > 3, P'' < 0, because the rate of population growth is slowing down.
Thus, if the population is in the final phase of logistic growth, the population is increasing at a decreasing rate (TRUE)..
Fertilization generally occurs in the fallopian tube.