Term
| DNA is not completely stable; the spontaneous loss of amino groups from adenine, for example, results in hypoxanthine, an unnatural base, opposite thymine. What combination of molecules could the cell use to repair this base mis-match? |
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Definition
| nuclease, DNA polymerase, DNA ligase |
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Term
| Mutagens can cause mutations by |
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Definition
a. Chemically altering DNA nucleotides
b. Disrupting DNA replication
c. Altering the genetic code of the organism
d. All of the above
answer: e. "a" and "b" only |
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Term
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Definition
| a form of damaged DNA caused by UV-irradiation |
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Term
| Oncogenes can be caused by: |
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Definition
a. Missense mutations
b. Gene amplification
c. Chromosomal translocation
d. Retroviral insertion
answer: e. All of the above |
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Term
| Which of the following is no longer necessary to get human cells that have turned malignant to reproduce in cell culture? |
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Definition
a. Nutrients
b. Anchorage to a substratum
c. Elbow room (i.e., not too dense a layer)
answer: d. "b" and "c" only |
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Term
| The Ames test is used to: |
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Definition
| a. determine the mutagenicity of various chemicals |
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Term
| Point mutations that do not alter the amino acid sequence of the resulting gene product are called ___ mutations. |
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Definition
|
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Term
| A mutation in which of the following regions is least likely to affect gene function? |
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Definition
|
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Term
| Which of the following is necessary to get human cells to reproduce in cell culture? |
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Definition
a. Nutrients
b. Growth factors
c. Anchorage to a substratum
d. Early developmental state (not too differentiated)
e. Elbow room (i.e., not too dense a layer)
answer: f. All of the above |
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Term
| When cells in cell culture form a complete single layer, they stop dividing. This is called |
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Definition
| density-dependent inhibition |
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Term
| A sequence in the mRNA is CUA instead of CGA. CUA codes for Leucine, whereas CGA codes for Arginine. This is the result of a mutation in the DNA that is |
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Definition
|
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Term
| Scientists have discovered a gene (BRCA1), mutations in which confer an 85% lifetime risk of breast cancer. Without the protein product of the normal BRCA1 gene, normal breast cells may turn cancerous, that is |
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Definition
| cancer cells do not exhibit density-dependent inhibition |
|
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Term
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Definition
| Mutations that result in AA substitutions that allow continued function of the protein product |
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Term
| DNA is not completely stable; the spontaneous loss of amino groups from adenine, for example, results in hypoxanthine, an unnatural base, opposite thymine. What combination of molecules could the cell use to repair this base mis-match? |
|
Definition
| nuclease, DNA polymerase, DNA ligase |
|
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Term
|
Definition
| escaped from cell cycle controls |
|
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Term
| Bacterial reproduction requires |
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Definition
a. an overall doubling of the cell constituents
b. replication of the bacterial DNA
c. separation of two DNA loops into the daughter cells
answer: d. all of the others |
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Term
| Which checkpoint determines whether the cell has synthesized its entire DNA? |
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Definition
|
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Term
| Non-dividing cells are said to be in |
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Definition
|
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Term
| During the cell cycle, increases in the enzymatic activity of protein kinases are due to: |
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Definition
| activation of inactive kinase by binding to cyclin |
|
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Term
| The mechanics of cytokinesis in animal cells involves |
|
Definition
| . a contracting ring of microfilaments |
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Term
| Human sperm and ova contain ___ ___ chromosomes. ("Doublet" refers to the appearance of a pair of sister chromatids.) |
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Definition
|
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Term
| Where does meiosis occur in human beings? |
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Definition
|
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Term
| A karyotype is performed on one of Molly's white blood cells. It shows a pair of #1 chromosomes, a pair of #2's, a pair of #3's, and so forth, but has only one chromosome #23. She would be characterized as a: |
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Definition
|
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Term
| It would take about ___ rounds of cell division for one cell to multiply to ___ cells, that is, the number in the human body. |
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Definition
|
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Term
| Cytotechnologists take photomicrographs of chromosomes, which have bands on the chromosomes. These bands |
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Definition
| are produced by staining the chromosomes |
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Term
| Presumably, karyotypes of Joe Biden and Sarah Palin would differ in the following way: |
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Definition
| Sarah's would contain two X chromosomes, but Joe's would contain an X and a Y. |
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Term
| Scientists have decoded the dog genome - a boxer named Tasha. Tasha's high degree of inbreeding simplified the task of decoding her 2.4 billion-letter genetic code by reducing the differences between her 39 chromosome pairs. The fact that she is a female, however, left the team without a picture of the canine Y chromosome. Apparently dogs have a haploid number of: |
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Definition
|
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Term
| A new, "baby" cell goes through the cell cycle in the following order: |
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Definition
|
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Term
| Checkpoints during the cell cycle are important because they |
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Definition
| ensure the integrity of the cell's DNA. |
|
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Term
| During what phase of mitosis do chromatids segregate? |
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Definition
|
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Term
| Cytokinesis in plants is characterized by: |
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Definition
| Golgi-derived vesicles coalesce at the middle of the cell, forming a cell plate whose contents form a new cell wall |
|
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Term
| Sexual reproduction requires: |
|
Definition
a. meiosis
b. gamete formation
c. fertilization
answer: d. all of the others |
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Term
| Sexually produced offspring do not look exactly like their parents. That is because of |
|
Definition
a. Independent assortment of chromosomes
b. Crossing over during formation of chiasmata
c. Random fertilization
answer: d. All of the others
e. None of the others |
|
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Term
| More common than completely polyploid animals are mosaic polyploids, animals that are diploid except for patches of polyploid cells. How might a mosaic tetraploid arise? |
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Definition
| By a nondisjunction during mitotic anaphase |
|
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Term
It would take about ___ rounds of cell division for one cell to multiply to ___ cells, that is, the number in the human body.
Choose one answer. |
|
Definition
|
|
Term
| Cytotechnologists take photomicrographs of chromosomes, which have bands on the chromosomes. These bands |
|
Definition
| are produced by staining the chromosomes |
|
|
Term
In San Francisco in 1977, Jennifer Chang (13) was hospitalized from eating poisonous mushrooms, resulting in serious liver damage. During her hospital stay, doctors grafted part of a donor liver onto her damaged one to help her liver cells regenerate. This therapy relies on the ability of resting liver cells to return to the mitotic cell cycle at the point they had left it, that is,
Choose one answer. |
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Definition
|
|
Term
| During the cell cycle, increases in the enzymatic activity of protein kinases are due to: |
|
Definition
| activation of inactive kinase by binding to cyclin |
|
|
Term
| A contracting ring of microfilaments is responsible for cytokinesis in |
|
Definition
|
|
Term
| The mechanics of cytokinesis in animal cells involves: |
|
Definition
| a contracting ring of microfilaments |
|
|
Term
An early event in mitosis is the migration of two ___ around the periphery of the nucleus to establish the poles of the subsequent mitotic process.
Choose one answer. |
|
Definition
|
|
Term
| Sexually produced offspring do not look exactly like their parents. That is because of |
|
Definition
a. Independent assortment of chromosomes
b. Crossing over during formation of chiasmata
c. Random fertilization
answer: d. All of the others |
|
|
Term
|
Definition
| the four closely associated chromatids during synapsis |
|
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Term
| How many genetically diverse gametes could be formed by meiosis in an organism whose somatic (body) cells are discovered to have eight chromosomes? (Ignore recombination.) |
|
Definition
|
|
Term
| A karyotype is performed on one of Molly's white blood cells. It shows a pair of #1 chromosomes, a pair of #2's, a pair of #3's, and so forth, but has only one chromosome #23. She would be characterized as a: |
|
Definition
|
|
Term
| Aneuploidies are more common in |
|
Definition
| Spontaneously aborted fetuses than in live births. |
|
|
Term
|
Definition
| . the distribution of DNA molecules must be regulated to insure that each daughter cell gets one |
|
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Term
| A species called widget is investigated. When a karyotype analysis is done, researchers see 30 "doublet" chromosomes ( =====) with a connection point near the center of the doublet. Widget sperm and ova would contain ___ chromosomes. |
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Definition
|
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Term
| Of the periods below, which is the longest? |
|
Definition
answer: a. G1
b. S
c. G2
d. Mitosis |
|
|
Term
| Of the periods below, which is the shortest? |
|
Definition
a. G1
b. S
c. G2
answer: d. Mitosis |
|
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Term
|
Definition
| M phase contains mitosis and cytokinesis |
|
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Term
| During anaphase the chromatids move toward the poles by a process that involves: |
|
Definition
| . the chromatids walking poleward along the kinetochore microtubules |
|
|
Term
| The spindle is formed by the aggregation of many |
|
Definition
|
|
Term
| The spindle fibers are disassembled into tubulin during |
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Definition
|
|
Term
| Which comes first in meiosis? |
|
Definition
| Separation of homologous chromosomes |
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Term
| Down syndrome is an example of: |
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Definition
|
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Term
| Iowa is full of corn. A karyotype of Iowa corn shows that it has ten different kinds of chromosomes, but that corn is tetraploid. Thus, a cell from the roots of a corn plant would have ___ chromosomes. |
|
Definition
|
|
Term
| The mechanics of cytokinesis in animal cells involves: |
|
Definition
| contracting ring of microfilaments |
|
|
Term
|
Definition
| the four closely associated chromatids during synapsis |
|
|
Term
| Aneuploidies are more common in |
|
Definition
| Spontaneously aborted fetuses than in live births |
|
|
Term
| point mutations that do not alte the amino acid sequence oftheresulting gene product are called____ nutations. |
|
Definition
|
|
Term
| oncogenes can be caused by: |
|
Definition
a. gene amplification
b. chromosomal translocation
c. retroviral insertion
answer: d. all of the other four answers
e. missense mutations |
|
|
Term
| In ten generations, a single cell can reproduce to become |
|
Definition
|
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Term
|
Definition
|
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