Answer: Codon
Explanation:
Codon refers to nucleotide triplets of mRNA that serve to specify the amino acid sequence of proteins. There are total 64 genetic code that specify 20 standard amino acids found in proteins. All codon together make genetic code. For example: AUG is codon that specify amino acid "methionine". AUG codon also serve as initiation codon during initiation of protein synthesis.
The correct answer is option 3, that is, lysosome.
The lysosomes comprise hydrolytic enzymes essential for intracellular digestion. They are commonly found in the cells of animals but are rare in plant cells. In the plant cells, the hydrolytic enzymes are most often found in the vacuoles.
The other mentioned components like cell wall are exclusively found in plant cells, not in animal cells, vacuole is found in both plant and animal cells, it is bigger in plant cells in comparison to animal cells, and the mitochondria are witnessed in both plant and animal cells.
Erythropoiesis is the formation of the red blood cells a process which takes place in the bone marrow. All blood cells are formed in the bone marrow, a soft, highly cellular tissue that fills the internal cavities of the long bones. It takes place in 8 stages where the first seven steps takes place within the bone marrow and after the 7th step the red blood cell is released into the blood stream as reticulocyte which then matures to erythrocyte after 1-2 days.