Answer:
Altruism is a form of prosocial behavior, which is used to describe a person who is helping someone with no intention of having any internal or external reward in return. Some psychologists suggest that altruism is a key motivation for prosocial behavior.
Answer:
B. As you get too hot, you sweat to cool your body temperature back down.
Answer:
Explanation:
Muscle contraction is stimulated by the movement of an action potential moving along a nerve fiber to the muscles. This event follow some series of process before being stimulated.
1. The impulse arrives at the synapse and travels through the transverse tubules.
2. The muscle impulse reaches the sarcoplasmic reticulum and calcium is released.
3. Calcium floods the sarcoplasm and binds to troponin molecules leaving active sites.
4. Tropomyosin molecules bind to exposed active sites, linking actin and myosin.
5. Thin filaments are pulled over the thick filaments.
6. The muscle fiber shortens and contracts.
Competition killed off all the organisms without traits that were benefitial to them. The organisms in the Galapogos Islands, such as the finches, made adaptions to settle in their new environment.
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.
