C the earth because that is the only planet around so he thought that the sun and everything else rotated around us.
Answer:
<u>A common element among all the river valley civilizations was irrigation systems that moved water to crops and settlements</u>
Explanation:
- <u>River Valley civilizations where the civilizations that were found on the banks of the river like the Mesopotamia ,Indus valley civilization.</u>
- <u>These civilization where agriculture based civilization as they depended on river for drinking water and irrigational activities</u>
Answer:
1. Nucleus
2. Nuclear DNA
3. Chromosomes. They contain the DNA.
4. This is DNA. DNA contains the instructions needed for an organism to develop, survive and reproduce.
Answer:
NAD is a coenzyme found in all cells. It consists of two nucleotides linked through their phosphate groups with a nucleotide that contains an adenosine ring and another that contains nicotinamide.
Explanation:
In metabolism, NAD participates in oxidation reduction reactions. This coenzyme is found in two forms in the cells: NAD and NADH. NAD accepts electrons from other molecules and is reduced, forming NADH, which you can use as a reducing agent to donate electrons. These electron transfer reactions are the main function of the NAD.
In living organisms, NAD can be synthesized from scratch from the amino acids tryptophan or aspartic acid. Some NADs are found in nicotinamide adenine dinucleotide phosphate (NADP), whose chemistry is similar to NAD, although it has different functions in metabolism.
