The sole reason why red blood cells are unable to replace damaged proteins is that red blood cells lack DNA and cell organelles such as nucleus, ribosomes and mitochondria which are crucial for protein synthesis, assembly and repair. In other words they lack both the information and the machinery for making or repair of proteins.
Due to lack of DNA and cell organelles, red blood cells cannot be able satisfy the central dogma which summarizes synthesis of proteins as DNA → RNA → proteins.
DNA has the genetic information on how proteins should be made, RNA is responsible for transferring the information from DNA in the cell nucleus to the ribosomes in the cytoplasm, then translating or decoding this information, which results in the making of protein.
Explanation:
The small number behind each element symbol designates the number of atoms of each element in a chemical formula. If there is no number, it is assumed there is only one of those elements. A large number designates how many units there are of that compound.
The best answer is C.
Chloroplasts are not found in all eukaryotic cells but only in plant cells. Animal cells are eukaryotic in nature but animals do not have chloroplasts in their cells because they do not engage in photosynthesis.
Photosynthesis is the process by which plants make their own food. Chloroplasts contain chlorophyll which is essential in t trapping sunlight from which supplies the energy for photosynthesis.
Animals do not make their own food like plants but eat ready made food so their cells lack mechanisms for food manufacture.