I’m not sure but I’m guessing the answer would be the first one !
Sister chromatids are two identical copies of Chromosome that is formed by the replication of a single chromosome.
This copies are formed during mitosis. Later on, these two sisters chromatids will grown into two different Cells
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It would be epithelial tissue that covers it.
<span>The organic chemicals that help
cell membranes to conserve internal fluids are the phospholipids. They are
composed of fatty acid, glycerol, phosphate group and a polar molecule. The phosphate
group and polar head region of the phospholipids is attracted to water while
the fatty acid is repelled by water. They are a major component of the cell
membrane in which it encloses the organelles of the cell. It also limits what
enters and exits the cell because of its two heads.</span>