biology unit test

Which describes something that occurs during translation?

A DNA template is used to create an mRNA strand. A tRNA template is used to create a DNA strand. A tRNA template is used to create an mRNA strand. An mRNA template is used to create an amino acid chain.

What must occur for protein translation to begin?

A water molecule must be added to the protein chain. A peptide bond must form between subunits of mRNA. The amino acid Cys must be picked up by tRNA. The codon AUG must be identified.

James is working with the lac operon of Escherichia coli (E. coli). He places the bacteria on a plate of growth media. Based on the current understanding of this operon, which hypothesis would be useful for James to test?

Addition of allolactose (inducer) to the bacterial growth media should increase the speed at which the bacteria metabolize the sugar lactose. Removal of the RNA polymerase molecule should increase the amount of bacterial growth on the plate. Decreasing the amount of allolactose (inducer) in the bacterial growth media should increase the rate of bacterial growth. Increasing the rate at which RNA polymerase acts will inhibit bacterial growth.

A DNA strand has the sequence GTTCCAGAG. Which is the complementary strand of RNA?

CAAGGTCTC AGGTTCACA CAAGGUCUC TGGAACTCA

What was Friedrich Miescher's contribution to the discovery of the genetic code?

He created the first photograph of the structure of DNA. He discovered how the DNA bases pair together. He created the first accurate model of DNA's structure. He extracted and observed DNA from white blood cells.

Which best matches a type of genetic material with its description?

Nucleotides form a helical structure that is called a gene. Genes combine to form structures called nucleotides. Chromosomes create genes. DNA is located in the nucleus.

Which best summarizes the process of protein synthesis?

RNA instructs DNA to make proteins. DNA unzips, resulting in the formation of two protein molecules. RNA moves the DNA code to the ribosomes for protein synthesis. DNA makes proteins in the nucleus.

Which is an arrangement of genes consisting of an operator, a promoter, and a repressor?

RNA polymerase anticodon codon operon

Maria is concerned because she has been exposed to a small amount of radiation during an X-ray. What is her doctor most likely to tell her?

Radiations from X-rays is not a mutagen. Mutagens have no effect on the body unless you have inherited them. Small amounts of a mutagen often do not have an effect on health. Severe mutations are usually caused by small amounts of a mutagen.

Who first identified DNA?

Rosalind Franklin Erwin Chargaff Friedrich Miescher James Watson

Which best describes genetic mutations?

Some inherited genetic mutations can be good for the offspring. Different genetic mutations cause few forms of cancer. Somatic mutations can be inherited from parents or acquired during life. Genetic mutations that cause diseases are always passed on to offspring.

A forensic scientist is trying to find out the number of adenine bases in the DNA sample that he obtained from a crime scene. What can he assume about the number of adenine?

The number of adenine bases will be equal to the number of guanine bases. The number of adenine bases will be equal to the total of all the other bases. The number of adenine bases will be equal to the number of thymine bases. The number of adenine bases will be half of the number of cytosine bases.

The study of Escherichia coli (E. coli) led researchers to new experimental designs for studying operons. Which experimental design did the scientists use?

Used a microscope to observe cell division to determine the structure of operons. Tested the response of E. coli to a variety of chemicals to determine the number of operons that are present. Inserted the operons from one organism into another to determine the mechanism of operon expression. Read the genome sequence to determine the quantity and organization of operons.

Which of the following correctly organizes these genetic terms in order from smallest to largest?

chromosome, gene, nucleotide, DNA molecule nucleotide, gene, DNA molecule, chromosome DNA molecule, nucleotide, gene, chromosome DNA molecule, nucleotide, chromosome, gene

Rosalind Franklin is famous for which contribution to the study of DNA?

creation of an accurate model of DNA structure creation of an X-ray diffraction image of DNA structure identification of a pattern in ratios of DNA bases identification of DNA in bandages that contained pus

Which of the following could be a nucleotide of RNA?

deoxyribose + phosphate group + thymine deoxyribose + phosphate group + uracil ribose + phosphate group + thymine ribose + phosphate group + uracil

How many genes make up the human genome?

four: adenine, thymine, guanine, and cytosine 23 pairs of genes 20,000-25,000 genes 3 billion genes

Which of these is the primary site of protein synthesis?

mitochondria cytoplasm nucleus ribosomes

The diagram shows a nucleic acid in the shape of a double helix. Which sugar is present in the nucleic acid that is represented in the diagram?

phosphate uracil deoxyribose ribose

Many different types of mutations can occur within the body. Cystic fibrosis is a genetic disorder that is caused by different mutations within the CFTR gene. One mutation in the CFTR gene that leads to cystic fibrosis causes translation to end earlier in the gene sequence. Which type of mutation causes this translation error that leads to cystic fibrosis?

silent missense nonsense deletion

Many different types of mutations can occur within the body. Sickle cell anemia is a disease that occurs when a mutation in a base pair of the hemoglobin beta gene causes a single replacement of the amino acid glutamic acid by the amino acid valine. As a result of this mutation, the individual's blood cells take on a sickle shape under certain conditions and form clusters that can block blood vessels and cause organ damage. Which type of mutation causes sickle cell anemia?

silent missense insertion frameshift

Which is a frameshift mutation?

substitution nonsense silent deletion

What is the role of RNA?

to provide the original blueprint for protein production to move information from the ribosomes to the nucleus for protein synthesis to break down proteins into amino acid monomers to move information from the nucleus to the ribosomes for protein synthesis

The diagram shows one step in the process of protein synthesis. Which step is shown?

transpiration translocation transcription translation

What can a person do to limit exposure to X-rays?

wear sunblock avoid cigarette smoke wear a protective vest avoid chemicals