Answer: Option D.
Sexual isolation.
Explanation:
Sexual isolation is a process in which a species of organism is unable to breed or mate from related species successfully due to environment, physiological, behavioral or genetic difference making its to depend on species involved in the cross. Examples is found in amphibians frogs and toads. Breakdown of sexual isolation lead to hybrid sterility, hybrid invaibility or poor gene flow.
The building blocks of protein are C. AMINO ACIDS.
Amino acids are made up of a center carbon atom bound positively to a charged amino group and a negatively charged carboxyl group and a side chain.
The primary structure of a protein is the sequence of an amino acids that are attached together by a peptide bond
The secondary structure of a protein, the polypeptide is folded through the mechanisms of amino acids rotating around bonds folding into a helix or a pleated sheet structure and stabilized by a hydrogen bond.
All living organisms are connected between each other because they have shared ancestor. I suggest you to read some stuff about evolution to make it more clear to understand.
1.Animal Cells : During cytokinesis, the cytoplasm splits in two and the cell divides. In animal cells, the plasma membrane of the parent cell pinches inward along the cell's equator until two daughter cells form
2.Plant Cells: During cytokinesis, the cytoplasm splits in two and the cell divides. In plant cells, a cell plate forms along the equator of the parent cell. Then, a new plasma membrane and cell wall form along each side of the cell plate.
3.The cell cycle, the process by which cells progress and divide, lies at the heart of cancer. In normal cells, the cell cycle is controlled by a complex series of signaling pathways by which a cell grows, replicates its DNA and divides. This process also includes mechanisms to ensure errors are corrected, and if not, the cells commit suicide (apoptosis). In cancer, as a result of genetic mutations, this regulatory process malfunctions, resulting in uncontrolled cell proliferation.
1.) atom ; tissue
2.) cell
3.) organ system
4.) true
5.) atom
6.) Particle
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