When a solution of cesium chloride (CsCl) is subjected to high-speed centrifugation, a stable density gradient is formed. Meselson and Stahl found that when cell contents were subjected to centrifugation with a CsCl solution, a band of DNA formed at the CsCl density that matched the density of the DNA. This technique is called density-gradient centrifugation. a. True
b. False

True

Explanation:

Messelson and strahl explain the semiconservative existence of DNA replication by using CsCl gradient centrifugation. The hardest would go and rest at the base of the test tube, while the lightest would be at the top, the lightest would find a position between the heavy and the lightest. When the heavy tube is centralized, from a pool of light, bulky and moderate DNA.

This technique is called density-gradient centrifugation. Hence, the given statement is true.

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.