Download Indicate whether the statement is true or false. If false

Final Review
Modified True/False
Indicate whether the statement is true or false. If false, change the identified
word or phrase to make the statement true.
____
1. A trait is a specific characteristic that varies from one individual to another. _________________________
____
2. An organism with a dominant allele for a particular form of a trait will sometimes exhibit that trait.
_________________________
____
3. Mitosis results in two cells, whereas meiosis results in one cell. _________________________
____
4. The replication of a DNA molecule results in four copies of the same gene. _________________________
____
5. If a nucleic acid contains uracil, it is DNA. _________________________
____
6. A codon consists of four nucleotides. _________________________
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7. The anticodon AGA is complementary to the mRNA codon TCT. ___________________
____
8. People have used selective breeding to produce many different dog breeds. _________________________
____
9. In a human karyotype, 44 of the chromosomes are autosomes. _________________________
____ 10. In a human karyotype, 23 chromosome pairs are similar in size and shape. _________________________
____ 11. A dominant X-linked trait would be more common in males than in females. _________________________
____ 12. If a cat has both orange and black spots, it is homozygous for the alleles on the X chromosome that code for
spot color. _________________________
____ 13. In natural selection, human breeders, rather than the environment, select the variations of traits to be passed to
offspring. ______________________________
____ 14. According to Darwin, the word selection would indicate organisms’ ability to survive and reproduce in their
particular environments. _________________________
____ 15. The fact that species today look different from their ancestors can be described as descent with modification.
_________________________
____ 16. According to Charles Darwin, members of a species must share limited resources.
_________________________
____ 17. A polygenic trait is controlled by one gene. _________________________
____ 18. In a population of snakes with a range of body lengths, if the longest individuals have the highest fitness,
disruptive selection is likely to occur. _________________________
____ 19. In small populations, an allele can become more or less common simply by chance.
_________________________
____ 20. In a lysogenic infection, host cells can make copies of virus DNA for many generations.
_________________________
____ 21. A disinfectant is a chemical solution that kills bacteria. _________________________
____ 22. An antibiotic is a preparation of weakened or killed virus or viral proteins. _________________________
Completion
Complete each statement.
23. The different forms of a gene are called ____________________.
24. In regards to plant height, the possible genotypes of a pea plant are TT, ____________________, or tt.
25. When two heterozygous tall pea plants are crossed, the expected genotype ratio of the offspring is
_________________________.
Figure 12–1
26. The structure labeled X in Figure 12–1 is a(an) ____________________.
Figure 12–3
27. In Figure 12–3, A, B, and C are three types of ____________________.
28. The order of nitrogenous bases in DNA determines the order of ____________________ in proteins.
29. The tRNA bases called the ____________________ are complementary to three consecutive nucleotides on
one mRNA molecule.
30. Humans use selective breeding to pass desired _________________________ on to the next generation of
organisms.
31. To produce a fruit that has some characteristics of an orange and some of a grapefruit, you would use the
selective breeding technique of _________________________.
32. Genetic defects caused by excessive inbreeding can be eliminated through the process of
_________________________.
33. Scientists use radiation and chemicals to induce ____________________.
34. Darwin proposed that natural selection took place as individuals best suited to the ____________________
survived and reproduced.
35. Crossing-over can occur during the meiotic divisions that produce cells called ____________________.
36. For new species to evolve, populations must be ____________________ isolated from each other.
Figure 19–2
37. The organism labeled A in Figure 19–2 is an example of a(an) ____________________.
38. The process of converting nitrogen to a form plants can use is called _________________________.
39. By breaking down the nutrients from dead organisms in an ecosystem, bacteria act as
____________________.
40. Although viruses come in many different shapes, the core of every virus contains ____________________.