I think it is the 3rd one because health problems at older age.
Chromatin
Chromosome, the highest packing level of DNA, is packed in nucleus. DNA strand itself is packed in chromatin. Chromatin is DNA packaging into 30nm fibers that involve DNA strand with scaffolding around DNA proteins, like histones, in eukaryotic cells’ nucleus.
Explanation:
The DNA strand is folded into nucleosomes, bead-like structures on the DNA and fold up into the 30nm fibers. During meiosis and mitosis, the chromatin is super-coiled up into thicker fibers called chromosomes. Chromosomes within the nucleus can be viewed by a light microscope in a cell in metaphase.
Learn More:
For more on levels of DNA check out;
brainly.com/question/8157150
brainly.com/question/2207292
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Before your food passes from the mouth and down your esophagus, salivary amylase, an enzyme in saliva, begins to digest the starch in your bread. That is the start of chemical digestion. ... The passage of the bolus through the esophagus to the stomach occurs by peristalsis, a series of wave-like muscle contractions.
Pregnancy. the body needs to gather nd make a new set of cells to build the baby