I'm not sure, but my best answer would be "C". Hope this helps, sorry if it doesn't.
Answer:
For functioning of heart, circulatory and execratory systems are required.
Explanation:
It requires at least two body systems to perform the function because the functions does not be completed solely, it requires coordination among systems which help them to fulfill their task. For example, the function of the heart requires circulatory system and execratory system for the pumping of blood throughout the body. it is an involuntary action which is not control by nervous system.
Answer: Semiconservative
Explanation:
By using the strand as a template, it conserves the information from half of the DNA molecule. By the end of replication, it contains one original strand and one strand which is newly synthesized.
The NOAA estimates that 50% to 80% of earth's oxygen is produced from the ocean.
