Question

complete the following paragraph to describe the role of ribosomes in protein synthesis.
ribosomes are the sites of _________ in both prokaryotic and eukaryotic cells.
they are comprised of _______ subunits that are each composed of protein and _______.
in eukaryotic cells, they occur in the _______ singly or in groups called _______.
ribosomes receive _______ that was transcribed in the nucleus and recruit _______ to form a polypeptide chain.
sometimes, when the protein being synthesized begins with a _______, the ribosome binds to the _______ where the protein is further folded and modified.
options: rrna, signal peptide, polyribosomes, cytoplasm, amino acids, mrna, protein synthesis, two, endoplasmic reticulum

Explanation:

1st blank:

Ribosomes are the sites of protein synthesis (as ribosomes are known to be the location where proteins are made in cells).

2nd and 3rd blanks:

They are comprised of two subunits (ribosomes have a large and a small subunit, so two subunits in total) that are each composed of protein and rRNA (ribosomal RNA is a key component of ribosomal structure along with proteins).

4th and 5th blanks:

In eukaryotic cells, they occur in the cytoplasm (free ribosomes are in the cytoplasm) singly or in groups called polynibosomes (groups of ribosomes translating the same mRNA are called polyribosomes).

6th and 7th blanks:

Ribosomes receive mRNA (messenger RNA carries the genetic code from DNA in the nucleus to the ribosome) that was transcribed in the nucleus and recruit amino acids (amino acids are the building blocks of proteins, and ribosomes assemble them into polypeptide chains).

8th and 9th blanks:

Sometimes, when the protein being synthesized begins with a signal peptide (a signal peptide is a sequence that directs the ribosome - nascent chain complex to the endoplasmic reticulum), the ribosome binds to the endoplasmic reticulum (the endoplasmic reticulum is where proteins with signal peptides are further processed, folded, and modified).

Filled Paragraph:

Ribosomes are the sites of $\boldsymbol{\text{protein synthesis}}$ in both prokaryotic and eukaryotic cells.

They are comprised of $\boldsymbol{\text{two}}$ subunits that are each composed of protein and $\boldsymbol{\text{rRNA}}$.

In eukaryotic cells, they occur in the $\boldsymbol{\text{cytoplasm}}$ singly or in groups called $\boldsymbol{\text{polynibosomes}}$.

Ribosomes receive $\boldsymbol{\text{mRNA}}$ that was transcribed in the nucleus and recruit $\boldsymbol{\text{amino acids}}$ to form a polypeptide chain.

Sometimes, when the protein being synthesized begins with a $\boldsymbol{\text{signal peptide}}$, the ribosome binds to the $\boldsymbol{\text{endoplasmic reticulum}}$ where the protein is further folded and modified.

Answer:

1st blank:

Ribosomes are the sites of protein synthesis (as ribosomes are known to be the location where proteins are made in cells).

2nd and 3rd blanks:

They are comprised of two subunits (ribosomes have a large and a small subunit, so two subunits in total) that are each composed of protein and rRNA (ribosomal RNA is a key component of ribosomal structure along with proteins).

4th and 5th blanks:

In eukaryotic cells, they occur in the cytoplasm (free ribosomes are in the cytoplasm) singly or in groups called polynibosomes (groups of ribosomes translating the same mRNA are called polyribosomes).

6th and 7th blanks:

Ribosomes receive mRNA (messenger RNA carries the genetic code from DNA in the nucleus to the ribosome) that was transcribed in the nucleus and recruit amino acids (amino acids are the building blocks of proteins, and ribosomes assemble them into polypeptide chains).

8th and 9th blanks:

Sometimes, when the protein being synthesized begins with a signal peptide (a signal peptide is a sequence that directs the ribosome - nascent chain complex to the endoplasmic reticulum), the ribosome binds to the endoplasmic reticulum (the endoplasmic reticulum is where proteins with signal peptides are further processed, folded, and modified).

Filled Paragraph:

Ribosomes are the sites of $\boldsymbol{\text{protein synthesis}}$ in both prokaryotic and eukaryotic cells.

They are comprised of $\boldsymbol{\text{two}}$ subunits that are each composed of protein and $\boldsymbol{\text{rRNA}}$.

In eukaryotic cells, they occur in the $\boldsymbol{\text{cytoplasm}}$ singly or in groups called $\boldsymbol{\text{polynibosomes}}$.

Ribosomes receive $\boldsymbol{\text{mRNA}}$ that was transcribed in the nucleus and recruit $\boldsymbol{\text{amino acids}}$ to form a polypeptide chain.

Sometimes, when the protein being synthesized begins with a $\boldsymbol{\text{signal peptide}}$, the ribosome binds to the $\boldsymbol{\text{endoplasmic reticulum}}$ where the protein is further folded and modified.