chapter 13 biology
What can you conclude about DNA replication from this diagram?
The two original strands are replicated in opposite directions.
Prokaryotic cells
These cells have a circular DNA molecule. DNA replication proceeds from a single starting point
Frederic Griffith discovered transformation in his experiments on mice and Pneumococcus bacteria. He injected the mice with combinations of harmless, R-strain bacteria and disease-causing S-strain bacteria. Which combination of bacteria killed the mice and showed that transformation occurred?
heat-killed S-strain and live R-strain
know that
hydrogen bonds = dotted lines covalent bonds = solid lines
A nucleotide of DNA may contain adenine, guanine, cytosine, or thymine. What is each of these components?
nitrogenous base
From left to right, what are the three components of the nucleotide shown in this model?
nitrogenous base, 5-carbon sugar, phosphate group ( 5 sides is 5 carbon sugar and circle phosphate group)
A strand of DNA is a polymer of___________ joined by covalent bonds between the__________ of one monomer and the___________ of the next monomer.
nucleotides deoxyribose phosphate group
what was the purpose of marketing the bacteriophages with phosphorus-32 and sulfur-35
to track the movements of DNA and protiens
Scientists wanted to learn more about Griffith's experiment. They extracted a mixture of various molecules from the heat-killed bacteria. They found that__________ no longer occurred when they treated the mixture with enzymes that destroyed_____________ . This experiment supports the hypothesis that_________ is the genetic material.
transformation DNA DNA
when does transformation occur?
when a cell receives foreign DNA that is expressed as a new characteristic
The statements below are steps of DNA replication. Rearrange the statements so they are in order with the first step at the top.
1 During S phase the two strands of the double helix are separated by enzymes. 2 Two DNA strands are synthesized that are complementary to each original strand. 3 DNA polymerase proofreads each DNA strand. 4 The two copies of DNA with a complete set of genes separate from each other in anaphase of mitosis.
What is needed for DNA replication? Select all that apply.
1 enzymes to break the hydrogen bonds of the DNA molecule 2 free nucleotides 3 polymerase to join nucleotides onto the template DNA strand
Eukaryotic cells
DNA and histones form nucleosomes. DNA replication may begin from many starting points. Telomeres are found at the tips of chromosomes. DNA is found in the nucleus, packaged into chromosomes
The principal enzyme involved in DNA replication is called_____________. The enzyme joins_________ to synthesize a new___________ strand of DNA . DNA replication is called ________ because each new DNA molecule is made up of one original and one new strand.
DNA polymerase nucleotide complementary semi conservative
Which of the four DNA strands match the strand in the diagram by base pairing? CCACTGA
GGTGACT
Which of these statements are supported by the data? Select all that apply.
In any one species, the amount of adenine closely approximates that of thymine. In any one species, the amount of guanine closely approximates that of cytosine. The amounts of A, T, G, and C in DNA varies from species to species.
Which statements describe a bacteriophage? Select all that apply.
It is a type of virus that infects bacteria. It is a virus consisting of a protein coat and a DNA core.
What are three tasks that DNA must be able to perform in all organisms? Select three answer choices.
It must store genetic information. It must instruct cells to produce needed molecules. It must copy itself.
Bacteriophage marked with phosphorus-32
Radioactivity is found inside the infected bacterium. Results confirm that DNA is the genetic material of the bacteriophage. Bacteriophage contains radioactive isotope that is used to mark DNA
Bacteriophage marked with sulfur-35
Results confirm that protein is not the genetic material of the bacteriophage. No radioactivity is found inside the infected bacterium. Bacteriophage contains radioactive isotope that is used to mark protein.
Rosalind Franklin's photographs of the X-ray diffraction pattern of DNA provided important clues about the structure of the DNA molecule.What was revealed by the photograph that enabled Watson and Crick to build their model of the DNA molecule? Select all that apply.
The DNA strands are twisted around each other. There are two strands in the DNA molecule. The nitrogenous bases are near the center of the DNA molecule.
know that
both use polymerase