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Biology, Study Guide
Introduction to Genetics, Ch. 11
Section 11:1
1. What is genetics and why do you think Garden Peas are a good
choice of organism for studying genetics?
2. Define the following:
 True breading –

Trait –

P generation –

F1 generation –

Hybrid
3. What type of F1 offspring is produced when true-breeding
plants are allowed to reproduce?
Name _________________________ Period _____
Class Notes:
4. Use figure 11-3 in the textbook to explain the F1 results of
Mendels’ crosses with the 7 contrasting traits.
5. What were Mendel’s first conclusions from the above
experiment?
What are traits called today?
What are alleles?
6. What was Mendel’s 2nd conclusion?
7. Explain the difference between dominant alleles and recessive
alleles.
8. Describe the result of the experiment in which Mendel allowed
the F1 hybrid plants to self-pollinate. What occurred in the F2
generation?
9. What is segregation and what happens to alleles during
segregation?
Class Notes:
Section 11:2
10. Define probability.
11. If you flip a coin 5 times, what is the probability that the
results will all be tails?
12. How is flipping a coin relevant to genetics?
13. What is the purpose of using Punnett squares?
14. What is the difference between homozygous and heterozygous
organisms?
15. What is the difference between phenotype and genotype?
Class Notes:
16. Draw Punnett squares to determine the genotype and
phenotype ratios for offspring of the following crosses.
#1.
TT x tt (T = tall, t = short)
Results:
F1 genotype ratioF1 phenotype ratio #2.
TT x Tt
Results:
F1 genotype ratio F1 phenotype ratio #3.
Ss x ss (S = smooth pod, s = wrinkled pod)
Results:
F1 genotype ratio F1 phenotype ratio –
Leave this section for class notes to answer the question “What
is a test cross?”
Class Notes:
Section 11:3
17. What was Mendel trying to determine when he did the twofactor cross experiment.
18. Use Figure 11-10 on p. 271 to describe Mendel’s result when
crossed plants that were heterozygous dominant for round
yellow peas.
You may need some of the space below for class notes.
19. State the Principle of Independent Assortment:
20. Summarize Mendel’s Principles:
Class Notes:
21. Describe the following exceptions to Mendel’s Principles and
give an example of each:
 Incomplete Dominance -

Codominance –

Multiple Alleles –

Polygenic Traits –
22. Do Mendel’s principles apply only to plants? Explain by
giving an example.
Class Notes:
Section 11:4
23. Read the first two paragraphs of Section 11:4. What must
happen to each set of two genes (alleles) when gametes form?
24. Explain the meaning of the term homologous chromosomes.
25. Contrast the terms diploid and haploid.
26. Define the term Meiosis in your own words.
27. Describe what occurs during each of the following stages of
Meiosis I and Meiosis II.
Meiosis I
a. Interphase I (prior to Meiosis I) –
b. Prophase I –
Tetrad –
Crossing Over –
Class Notes:
c. Anaphase I –
d. Telophase I and Cytokinesis –
Note: The result of Meiosis I is _____ new daughter cells. The
two new cells have sets of chromosomes and alleles that are
____________________ from each other and from the parent
cell.
Why?
Meiosis II
Note: Neither daughter cell goes through chromosome
replication before Meiosis II.
e. Prophase II –
f. Metaphase II –
g. Anaphase II –
h. Telophase II and Cytokinesis –
Note: Each of the _______ daughter cells contain the
_____________ number of chromosomes.
Class Notes:
28. How many male gametes are produced by meiosis? How
many female gametes?
29. Contrast Mitosis and Meiosis.
Section 11:5
30. When studying Fruit Flies, Morgan discovered that many
genes were inherited together. He discovered the Principle of
Linkage. Explain this principle.
31. Does the principle of linkage go against Mendel’s Principle of
Independent Assortment? Explain.
32. Explain how crossing over can unlink linked genes.
33. What did Sturtevant reason about the distance between genes
and crossing over?
34. What is a gene map?
Class Notes: