Question

synthesis & viral hijacking practice
statements to sort into the empty boxes:

• considered non-living
• much smaller than cells
• can be treated with antibiotics
• contains genetic material (dna or rna) inside a protein coat.

1. how do viruses primarily disrupt cellular processes to cause disease?

a) they release toxins that destroy the cell membrane immediately.
b) they block gene expression and prevent the host cell from replicating its own dna.
c) they hijack the host cells machinery to build more viral products.
d) they consume the cells mitochondria to produce energy for themselves.

part 4: protein synthesis & gene expression
word bank: ribosome, transcription, translation, nucleus, mrna, amino acids

protein synthesis occurs in two main stages. first, during ________ the dna code is copied into a strand of ______. this happens inside the ________ because dna cannot leave.
the mrna then travels to the ________ where the second stage, ______ occurs. here, trna molecules bring specific ________ to build the polypeptide chain based on the codons.

use the codon chart in the next section to find the amino acid sequence.

1. if an mrna sequence is ucu-ugu - cga, what is the resulting amino acid sequence? (find each triplet on the chart)

a) ser - cys - arg
b) thy - asn - glu
c) cys - phe - leu
d) ser - trp - asp

1. a dna segment is mutated from atc-ggc to att-ggc. what type of mutation is this? (hint: only one letter changed!)

a) deletion (a letter was removed)
b) insertion (a letter was added)
c) substitution (one letter was swapped for another)
d) translocation (a section moved to a new place)

Explanation:

Step1: Solve virus disruption question

Viruses take over host cell machinery to replicate.

Step2: Fill protein synthesis blanks

Match terms to protein synthesis stages:

1. First stage: transcription (DNA to mRNA)
2. Copied into mRNA
3. Occurs in nucleus (DNA cannot leave)
4. mRNA goes to ribosome
5. Second stage: translation
6. tRNA brings amino acids

Step3: Solve mRNA to amino acids

Use codon chart:

• UCU = Ser, UGU = Cys, CGA = Arg

Step4: Identify DNA mutation type

Single nucleotide (C→T) swapped; this is substitution.

Answer:

Virus Disruption Question:

c) They hijack the host cell's machinery to build more viral products.

Protein Synthesis Fill-in-the-Blanks:

Protein synthesis occurs in two main stages. First, during transcription, the DNA code is copied into a strand of mRNA. This happens inside the nucleus because DNA cannot leave.
The mRNA then travels to the ribosome, where the second stage, translation, occurs. Here, tRNA molecules bring specific amino acids to build the polypeptide chain based on the codons.

Amino Acid Sequence Question:

a) Ser - Cys - Arg

Mutation Type Question:

c) Substitution (one letter was swapped for another)