Question

1. label the diagram.

a:
b:
c:
d: nucleotide bases
e:
f: protein
g:
h:

1. describe how the nucleus and ribosomes work together during protein synthesis. include at least 3 molecules.

1. explain how a change in dna can result in different traits in an organism.

1. sort this list into the appropriate categories listed in the chart below.

word list: mrna, ribosome, dna, nucleus, gene, nucleotide bases, proteins, cell membrane, protein synthesis

molecules\tcellular structures\tprocesses
\t\t
\t\t

Explanation:

Question 8 (Diagram Labeling)

Step1: Identify Structure A

Looking at the diagram, A is part of the DNA - related structure in the nucleus. DNA is made of nucleotide bases and has a double - helix structure. So A is likely DNA (since it's the double - helix part in the nucleus).

Step2: Identify Structure B

B is a strand coming out of the DNA transcription process. In protein synthesis, DNA is transcribed into mRNA. So B should be mRNA (messenger RNA), as it carries the genetic code from DNA to the ribosome.

Step3: Identify Structure C

C is associated with the DNA and the transcription process. RNA polymerase is the enzyme that synthesizes mRNA from DNA. So C is RNA Polymerase (the enzyme for transcription).

Step4: Identify Structure E

E has a structure that can carry amino acids and match with mRNA. tRNA (transfer RNA) is responsible for bringing amino acids to the ribosome. So E is tRNA (Transfer RNA).

Step5: Identify Structure G

G is the site where translation (protein synthesis) occurs, with mRNA and tRNA interacting. Ribosomes are the organelles where translation happens. So G is Ribosome.

Step6: Identify Structure H

H is the outer boundary of the cell (or the cell membrane? Wait, no, in the context of protein synthesis, but looking at the diagram, H is the cell membrane? Wait, no, the diagram shows a cell, and H is the cell membrane? Wait, no, maybe the nuclear membrane? Wait, no, the main cell membrane. Wait, but in the context of the cell, H is the Cell Membrane (the outer layer of the cell). But wait, in the protein synthesis context, maybe it's the cell membrane, but actually, looking at the diagram, H is the Cell Membrane (the boundary of the cell).

1. First, in the nucleus, DNA (a molecule) contains the genetic code. The process of transcription occurs where RNA polymerase (enzyme) uses DNA as a template to make mRNA (messenger RNA). This mRNA carries the genetic information from the nucleus to the ribosomes in the cytoplasm.
2. Then, ribosomes (which can be free in the cytoplasm or attached to the rough ER) are the sites of translation. tRNA (transfer RNA) molecules bring amino acids (the building blocks of proteins) to the ribosome. The ribosome reads the mRNA codons (three - nucleotide sequences) and matches them with tRNA anticodons.
3. The ribosome then links the amino acids together to form a polypeptide chain, which will fold into a protein. So the nucleus (where DNA is transcribed into mRNA) and ribosomes (where mRNA is translated into protein) work together: DNA in the nucleus is transcribed to mRNA by RNA polymerase. mRNA exits the nucleus and goes to the ribosome. tRNA brings amino acids to the ribosome, and the ribosome uses the mRNA code to assemble amino acids into proteins. The three molecules involved are DNA, mRNA, and tRNA (or also amino acids, ribosomes are organelles but molecules like DNA, mRNA, tRNA, amino acids are involved).

1. DNA contains genes, which are segments of DNA that code for proteins. A change in DNA (a mutation) can be a change in the nucleotide base sequence (e.g., substitution, insertion, deletion of nucleotide bases).
2. This change in the DNA sequence can lead to a change in the mRNA sequence (since mRNA is transcribed from DNA).
3. The change in mRNA sequence can then lead to a change in the amino acid sequence of the protein (because the ribosome reads the mRNA codons to assemble amino acids).
4. Proteins are responsible for the traits of an organism (e.g., enzymes, structural proteins, hormones). A change in the protein's structure or function (due to a change in amino acid sequence) can result in a different trait. For example, a mutation in the gene for hemoglobin can cause sickle - cell anemia, changing the trait of blood cell shape and function.

Answer:

A: DNA
B: mRNA (Messenger RNA)
C: RNA Polymerase
E: tRNA (Transfer RNA)
G: Ribosome
H: Cell Membrane

Question 9 (Nucleus and Ribosomes in Protein Synthesis)