Seasons are Winter, Spring, Summer And Fall. The Sun moving (orbiting earth) causes them. So in the winter, the sun is on the opposite side of the world, and that's why it is so cold. In the summer, the sun is facing straight at us. Other season's, the sun is kinda in between, if that is any help
Answer:
c. ¼ heavy, ¾ light
Explanation:
DNA replication follows semi conservative model which means that both the strands separate during replication and the newly formed DNA molecule has one old and one new strand. If instead of semi conservative, conservative mechanism is used, old strands will not separate from each other and the two newly synthesised DNA strands will come together to form a DNA molecule.
Here the cells were first grown in heavy 15N medium so all the DNA molecules had 15N and thus were heavy. Then the cells were transferred to 14N medium where only lighter 14N were available for replication process.
In first generation, 14N DNA molecules were synthesised from 15N DNA molecules so 1/2 DNA molecules were 15N and other half were 14N. In the second generation, 14N molecules will give rise to new 14N molecules and 15N molecules will also give rise to 14N molecules hence 1/4 molecules will be 15N (heavy) and 3/4 will be 14N (light).
Answer: The two elements found in sand are silicone and oxygen.
Explanation:
Sand is a granular substance that contain different smaller pieces of rocks and minerals. It is formed fromm weathering of rocks or breakdown of larger particles of rock into smaller pieces. Silicon dioxide or silica is a compound found in sand and also glass. Silicon dioxide is the chemical formula of sand. Silicon dioxide is formed when silicone reacts with two molecules of oxygen to form silicon dioxide. The major elements in sand is silicone and oxygen.