Ribosomes are essential organelles because they:Group of answer choicesLink ubiquitin to proteinsModify newly synthesised proteinsHave a catalytic function in protein synthesisAminoacylate the tRNA

Ribosomes are essential organelles because they have a catalytic function in protein synthesis.

Here's a step-by-step explanation:

1. Ribosomes are cell structures responsible for protein synthesis. They are found in both prokaryotic and eukaryotic cells.

2. The process of protein synthesis involves translating the genetic code (DNA) into proteins. This process is also known as gene expression.

3. The ribosome reads the sequence of the messenger RNA (mRNA) and, using the genetic code, translates the sequence into an amino acid sequence. This is the primary step in protein synthesis.

4. The ribosome then facilitates the bonding between the amino acids to form a polypeptide chain. This chain will fold into a functional protein.

5. Therefore, the ribosome's role in catalyzing the reaction that forms the peptide bonds between amino acids is crucial for protein synthesis.

So, the correct answer is: Ribosomes have a catalytic function in protein synthesis.