whose main job is to help an animal cell make proteins.
The correct answer and explanation is:
Correct Answer: Ribosome
Explanation (300 words):
In an animal cell, the ribosome is the organelle whose main job is to help make proteins. Ribosomes are small, complex molecular machines found in both prokaryotic and eukaryotic cells, and their essential function is to translate genetic information (mRNA) into proteins by linking together amino acids in the correct sequence.
Ribosomes can either float freely in the cytoplasm or be attached to the endoplasmic reticulum, making it the rough endoplasmic reticulum (RER) due to its “rough” appearance under a microscope. Those bound to the RER primarily produce proteins that are secreted from the cell or sent to the cell membrane, while free ribosomes make proteins that function within the cytoplasm itself.
Protein production starts when a gene in the DNA is transcribed into messenger RNA (mRNA) in the nucleus. The mRNA then exits the nucleus through nuclear pores and attaches to a ribosome. The ribosome “reads” the mRNA in codons (three-nucleotide sequences), and with the help of transfer RNA (tRNA), it adds the appropriate amino acids to the growing protein chain in the correct order.
The ribosome is made of ribosomal RNA (rRNA) and proteins, forming two subunits: a large and a small subunit. These subunits come together during protein synthesis and dissociate once the protein is made.
Without ribosomes, a cell could not produce the enzymes, structural components, or signaling molecules it needs to function. Thus, ribosomes are essential to life. In fact, because of their importance, nearly all living cells—animal, plant, bacterial—contain ribosomes, though their structure may differ slightly between cell types.
In summary, ribosomes are the primary organelles responsible for protein synthesis in animal cells, acting as the site where the genetic code is translated into functional proteins.