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1 | |
How many genes are believed to constitute the human genome? |
| | A) | one million |
| | B) | ten million |
| | C) | 100,000 |
| | D) | 70,000 |
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2 | |
During which meiotic division is the number of chromosomes halved? |
| | A) | during meiosis I |
| | B) | during meiosis II |
| | C) | prior to meiosis I, during the S phase |
| | D) | after meiosis II |
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3 | |
Choose the recessive human trait from the list that follows. |
| | A) | widow's peak |
| | B) | cheek dimples |
| | C) | hairless forearms |
| | D) | freckles |
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4 | |
During which phase of meiosis does the phenomenon called crossing-over occur? |
| | A) | prophase I |
| | B) | metaphase I |
| | C) | telophase I |
| | D) | prophase II |
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5 | |
Homologous chromosomes are separated during _______________. |
| | A) | prophase I |
| | B) | metaphase I |
| | C) | anaphase I |
| | D) | telophase I |
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6 | |
Which of these does not contribute to genetic variability? |
| | A) | meiosis |
| | B) | crossing-over |
| | C) | having children with a close relative |
| | D) | having children with someone who is not a relative |
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7 | |
Several variant forms of a gene for a given trait are called ______________. |
| | A) | autosomes |
| | B) | alleles |
| | C) | sex chromosomes |
| | D) | histones |
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8 | |
A person who can pass either a widow's peak or continuous hairline to the next generation is said to be _______________ for the hairline trait. |
| | A) | homozygous |
| | B) | heterozygous |
| | C) | incompletely dominant |
| | D) | recessive |
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9 | |
If a trait, such as hemophilia, occurs more often in males than in females, it is because the gene for the trait is most likely carried on ________________. |
| | A) | the X chromosome |
| | B) | the Y chromosome |
| | C) | a mutant allele |
| | D) | an autosome |
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10 | |
If Chris, who carries the gene for cystic fibrosis but does not have the disease, fathers a child with Rhonda, who also carries the cystic fibrosis gene but does not have the disease, what is the likelihood that their first-born will have cystic fibrosis? |
| | A) | 75% chance |
| | B) | 50% chance |
| | C) | 25% chance |
| | D) | 0% chance |
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11 | |
What is an example of a codominant trait in humans? |
| | A) | sickle cell disease |
| | B) | Huntington disease |
| | C) | ABO blood groups |
| | D) | Tay-Sachs disease |
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12 | |
Traits that are controlled by one or more genes and influenced by the environment are said to be _________________. |
| | A) | incompletely dominant |
| | B) | multifactorial |
| | C) | polygenic |
| | D) | incompletely penetrant |
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13 | |
The fact that a woman cannot generally grow a beard is because beard growth is a(n) ________________ trait. |
| | A) | completely penetrant |
| | B) | pleiotropic |
| | C) | sex-limited |
| | D) | sex-influenced |
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14 | |
Individuals with Turner syndrome have which genetic abnormality? |
| | A) | two X and one Y chromosomes |
| | B) | three copies of chromosome 13 |
| | C) | three copies of chromosome 18 |
| | D) | one X chromosome; no Y chromosome |
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15 | |
The normal chromosome number is referred to as _____________. |
| | A) | euploid |
| | B) | aneuploid |
| | C) | polyploid |
| | D) | tetraploid |
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16 | |
The last pair of 23 chromosomes is referred to as the _____. |
| | A) | karyotype |
| | B) | autosomes |
| | C) | nondisjunction chromosomes |
| | D) | sex chromosomes |
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17 | |
In Down's syndrome, there is an extra chromosome number _____. |
| | A) | 19 |
| | B) | 20 |
| | C) | 21 |
| | D) | 22 |
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18 | |
Which of the following is most common? |
| | A) | Patau syndrome |
| | B) | Edward syndrome |
| | C) | Klinefelter syndrome |
| | D) | Turner syndrome |
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19 | |
What is the most common chromosomal disorder in this group? |
| | A) | Patau's syndrome |
| | B) | Edward's syndrome |
| | C) | trisomy 13 |
| | D) | trisomy 21 |
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20 | |
Which chromosomes indicate a normal male fetus? |
| | A) | XX |
| | B) | XXY |
| | C) | XY |
| | D) | XYY |
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21 | |
What is the Turner's syndrome chromosome pattern? |
| | A) | XXY |
| | B) | XYY |
| | C) | XO |
| | D) | XXO |
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22 | |
Which of the following fetuses will not survive? |
| | A) | XXY |
| | B) | XYY |
| | C) | XXXY |
| | D) | YY |
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23 | |
Which chromosome pattern indicates a male with poor sexual development? |
| | A) | XYY |
| | B) | XXY |
| | C) | XY |
| | D) | XO |
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24 | |
What type of inheritance is present in a person who has blue eyes and received a blue-eyed gene from each parent? |
| | A) | autosomal dominant |
| | B) | sex-linked |
| | C) | recessive |
| | D) | genetic |
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2002 McGraw-Hill Higher Education