Answer:
hydrogen gas dominated earth's first atmosphere?
I think the cytoskeletal protein that helps a cell maintain its shape is actin.
A
Before meiosis begins, during S phase of the cell cycle, the DNA of each chromosome is replicated so that it consists of two identical sister chromatids, which remain held together through sister chromatid cohesion. This S-phase can be referred to as "premeiotic S-phase" or "meiotic S-phase".
Desmosomes
Desmosomes are cell junction that acts as anchors and distributes tension through a cellular sheet and reduces the chance of tearing when it is subjected to great mechanical stress.
Desmosomes are cell structure by which two adjacent cells are joined. Desmosomes are specialized for cell to cell contact and strong adhesion. The inactiveness of desmosomes can lead to diseases of the skin and heart. Desmosomes are found in tissue that undergo high mechanical stress, such as bladder tissue, epithelial, and cardiac muscle tissue.