Biology Chapter 11
1. Offspring that result from crosses between true-breeding parents with different traits are called
2. Gregor Mendel removed the male parts from the flowers of some plants in order to make
___________ crosses between plants.
3. The chemical factors that determine traits are _______________.
4. Gregor Mendel concluded that traits are _________________ through the passing of factors from
parents to offspring.
5. When Gregor Mendel crossed a tall plant with a short plant, the F1, plants inherited an allele for
_____________ from the tall parent and an allele for ___________ from the short parent.
6. When Gregor Mendel crossed true-breeding tall plants with true-breeding short plants, all the
offspring were tall because the allele for tall plants is ________________.
7. A tall plant is crossed with a short plant. If the tall F1 pea plants are allowed to self-pollinate, some
of the offspring will be ______________, and some will be ________________.
8. In the P generation, a tall plant was crossed with a short plant. Short plants reappeared in the F2
generation because the allele for shortness and the allele for tallness _____________ when the F1
plants produced gametes.
9. In the P generation, a tall plant was crossed with a short plant. If alleles did not segregate during
gamete formation, all of the F2 plants would be _________________.
10. When you flip a coin, what is the probability that it will come up tails is ______________.
11. The principles of probability can be used to predict the _______________ of the offspring
produced by genetic crosses.
12. In the P generation, a tall plant is crossed with a short plant. The probability that an F2 plant will be
tall is _______________________.
13. In the Punnett square shown in Figure 11-1, all are expected to be ___________________.
14. If you made a Punnett square showing Gregor Mendel’s cross between true-breeding tall plants
and true-breeding short plants, the square would show that the offspring had a genotype that was
______________________ from both parents.
RY Ry rY ry
RY RRYY RRYy RrYY RrYy R – round
r – wrinkled
Ry RRYy RRyy RrYy Rryy
RrYy Seed Color
Y – yellow
rY RrYY RrYy rrYY rrYy y – green
ry RrYy Rryy rrYy rryy
15. The Punnett square in Figure 11-2 shows that the gene for pea shape and the gene for pea color
16. How many different allele combinations would be found in the gametes produced by a pea plant
whose genotype was RrYY? _______________________
17. If a pea plant that is heterozygous for round, yellow peas (RrYy) is crossed with a pea plant that is
homozygous for round peas but heterozygous for yellow peas (RRYy), how many different
phenotypes are their offspring expected to show? __________________________
18. A cross of a red cow (RR) with a white bull (WW) produces all roan offspring (RRWW). This type of
inheritance is known as _______________________.
19. Variation in human skin color is a result of ___________________ ____________________.
20. Gregor Mendel’s principles of genetics apply to __________ ______________________.
21. A man and a woman who are both heterozygous for normal skin pigmentation (Aa) produce an
albino offspring (aa). Mendel’s principles that explain why the offspring is albino are
__________________ and _________________.
22. The number of chromosomes in a gamete is represented by the symbol ___________________.
23. If an organism’s diploid number is 12, its haploid number is _____________________.
24. Gametes have one ____________________ for each gene.
25. Gametes are produced by the process of _______________________________.
26. Figure 11-3 shows ___________ __________.
27. Chromosomes form tetrads during ______________________ of meiosis I.
28. What happens between meiosis I and meiosis II that reduces the number of chromosomes?
Replication (does /does not) occur.
29. Unlike mitosis, meiosis results in the formation of ________________ ______________.
30. Unlike mitosis, meiosis results in the formation of four genetically _________________ cells.
31. Crossing-over rarely occurs in mitosis, unlike meiosis because _________________ rarely form
32. ___________________ assort independently.
33. Gene maps are based on the ___________________ of crossing over between genes.
34. If two genes are on the same chromosome and rarely assort independently, the genes are probably
located _____________________ to each other.
35. The farther apart two genes are located on a chromosome; the less likely they are to be