Mendel and His Peas – Chapter 3, Section 1 – Pp 56-61
1. Who was Gregor Mendel?
a. Born 1822
i. Heinzendorf, Austria
b. Farm
i. Learned about flowers and fruit trees
c. Monastery
i. Age 21
d. Scientific experiments
i. Discovered principles of heredity
1. Monastery Garden
2. Compare and contrast self-pollination and cross-pollination
Self-Pollination
Cross-Pollination
Both male and female
Either male or female
Can fertilize itself
Needs pollen from a different plant
Doesn’t require help
Needs animals or wind
3. What is the difference between a characteristic and a trait?
Characteristic – A feature that has different forms in a population.
i.e. – Hair color
Trait – These different forms are traits. i.e. – Red hair or brown hair
4. Use pictures to summarize what Mendel did in his first experiment
5. Describe what Mendel found from his second set of experiments.
During his second set of experiments, Mendel allowed the firstgeneration plants, which resulted from his first set of experiments,
to self-pollinate. The recessive trait reappeared in the second
generation.
6. What is a ratio? What is the ratio of boys to girls in this class?
a. Ratio – A relationship between two numbers that can be expressed as
a fraction.
b. Ratio of boys to girls in this class –
17
16
Boys
Girls
15
14
Kids in Class - Period 2
17
16
15
Boys
14
Girls
13
12
Kids in Class - Period 3
18
17
Boys
16
Girls
15
14
Kids in Class - Period 4
7. Look at Table 1 on p. 60, which shows Mendel’s results. What do you notice
about the ratios of dominant to recessive traits?
All the ratios are about the same and call all be rounded to 3:1
8. In cats, there are two types of ears: normal and curly. A curly-eared cat
mated with a normal-eared cat, and all of the kittens had curly ears. Are
curly ears a dominant or recessive trait? Please explain.
Curly ears would have to be dominant. Just like in Mendel’s first
experiment, the first generation showed only one trait, in this case,
curly ears. A second generation has the potential to express normal
ears.