1) Some events that occur during protein synthesis
1) mRNA binds to a ribosome.
2) Transcription completes.
3) mRNA leaves the nucleus.
4) tRNA attaches to the start codon.
5) Ribosome reads the mRNA codons.
6) Stop codon marks the end of translation.
7) Amino acid attached to tRNAs bind to other amino acids, forming a protein chain.
List in sequence, the events numbered above that occur during protein synthesis.
Answer, Answer, Answer , Answer, Answer, Answer, and Answer
2) SEE IMAGE 1 ATTACHED
3) Forms of RNA Involved in Translation
1) Brings the appropriate amino acids to the ribosome.
2) Brings the genetic information from the nucleus to the cytoplasm.
3) Found in the ribosome.
Match the RNA to their roles in gene expression.
DescriptIon: Answer Answer Answer
RNA: mRNA rRNA tRNA
4) Indicate where each of the following processes occurs.
Translation Answer
Transcription Answer
DNA replication Answer
POSSIBLE ANSWERS: NUCLEUS, CYTOPLASM, MITOCHONDRIA
5) Like mRNA, tRNA has a ribose sugar, U instead of T, and is single stranded. Unlike mRNA, which remains a long single strand of nucleotides, tRNA folds so that some areas pair up. The resulting structure has an anticodon on one end and a site for an amino acid to attach on the other end. There is base complementarity (A pairs with U and G pairs with C) between an mRNA codon and tRNA anticodon.
If the amino acid lysine attaches to a tRNA, which of the following anticodons could be at the opposite end of the tRNA molecule?
a. AGA and AGU
b. AAA and AAG
c. UUU and UUC
d. UCU and UCA
6) A small section of bacterial mRNA has the following nucleotide sequence:
UAC AGA ACA CUG
The tRNA anticodons for the mRNA sequence shown above is
a. UUG UCU UCU GAC
b. TAC AGA ACA CTG
c. ATG TCT TGT GAC
d. AUG UCU UGU GAC
7) A small section of bacterial enzyme has the amino acid sequence threonine, valine, glycine, and methionine.
The tRNA anticodons for the amino acid sequence shown above is
a. UGA CAG CCA ACU
b. UGC CAA CCU UAC
c. ACC GUG GGC AUG
d. UGU CAU CCC UAG
8) A small section of bacterial DNA antisense strand has the following nucleotide sequence:
AAT CGG TCC TCG
The tRNA anticodons for the gene sequence shown above is
a. UUA GCC AGG AGC
b. AAU CGG ACC ACG
c. AAU CGG UCC UCG
d. TTA GCC AGG AGC
9) An enzyme such as ligase is a protein molecule. When high temperature is applied to ligase, the protein molecule changes its shape and is no longer able to perform its function. The enzyme is said to be denatured.
Consider the central dogma of molecular biology. If ligase was denatured in a cell, how would it affect its cell cycle?
a. The cell would not be able to transcribe DNA.
b. The cell would not be able to obtain amino acids.
c. The cell would not be able to produce protein molecules.
d. The cell would not be able to replicate.
10) Use the following information to answer the next two questions.
Permethrin is an insecticide that is used to treat mosquito nets to make them more effective in preventing the spread of malaria. A study found that some mosquitoes have become resistant to permethrin. The research included the following steps.
1) A sample of mosquitoes was treated with the insecticide.
2) The majority of the mosquito population died, but a small percentage survived.
3) From the survivors, a line of resistant mosquitoes was bred.
4) The DNA of the non–resistant strain was compared with DNA from the resistant strain.
What is most likely the purpose of this research?
a. To investigate the mosquito’s bodies
b. To test the insecticides
c. To breed resistant mosquitoes
d. To identify the resistant gene
11) Before analyzing the DNA, the researchers conducted an experiment to make sure they had produced a strain of resistant mosquitoes. This experiment included the following steps.
1) A sample of wild–caught mosquitoes and a sample of the resistant strain of mosquitoes were treated with permethrin.
2) The percentage of mosquitoes surviving in each sample was calculated.
The responding variable in this experiment was the
a. total mosquito sample
b. number of mosquitoes that survived
c. exposure of mosquitoes to permethrin
d. resistant mosquito sample
12) Some Sources of Mutation
Prolonged skin exposure to UV rays
Mother is a carrier of a sex–linked trait
Homologous chromosomes fail to separate during meiosis
DNA polymerase adds incorrect nucleotide during interphase of mitosis
Identify whether the sources of mutations listed above are somatic cell mutation or germ line mutation.
Somatic cell mutation
Germ line mutation
Types of Mutation: Answer Answer Answer Answer
Sources of Mutation: a b c d
13) Which of the following situations does not describes a chromosomal mutation?
a. The sister chromatids of Chromosome 18 do not separate during anaphase II.
b. A section of Chromosome 17 is duplicated leading to problems in the peripheral nervous system.
c. A portion of Chromosome 4 is deleted during interphase of meiosis.
d. A cytosine nucleotide is substituted for thymine nucleotide in a gene.