1. Copyright © by Holt, Rinehart and Winston. All rights reserved. Section 1 Mendel and His Peas Gregor Mendel: Who was he? Born 1822 in Austria Monk and a scientist/teacher He researched in the monastery garden. He discovered the principles of heredity Chapter C3 + ½ each = 2 pts

2. Copyright © by Holt, Rinehart and Winston. All rights reserved. Characteristics Mendel studied only one characteristic at a time. Characteristics- seed shape plant height flower color Section 1 Mendel and His Peas Chapter C3 + 1 each = 2 pts

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. Mix and Match Mendel wanted to find out what would happen if he bred or crossed two plants that had different traits of a single characteristic. Section 1 Mendel and His Peas Chapter C3 + 1 each = 1 pt

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. Pea Plant Experiments: What were his results? One trait was always present in the first generation and the other trait seemed to disappear. the trait that appeared =dominant trait. The trait that seemed to disappear = recessive trait. Section 1 Mendel and His Peas Chapter C3 Mendel’s 1 st Experiments + 1 each = 3 pts

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. In second-generation, the recessive trait reappeared. MOST plants had the dominant trait. Section 1 Mendel and His Peas Chapter C3 Mendel’s 2 nd Experiments + 1 each = 2 pts

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. The ratio between dominant & recessive traits The ratio was always about 3:1 (dominant : recessive) Section 1 Mendel and His Peas Chapter C3 + 1 pt

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. What conclusions did he make? His results could only be explained if : each plant had two sets of instructions for each characteristic. each parent donated one set of instructions Section 1 Mendel and His Peas Chapter C3 + 1 each = 2 pts

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. 30 Years after Mendel’s death: his work became widely recognized his ideas were rediscovered his work opened the door to modern genetics Section 1 Mendel and His Peas Chapter C3 + 1 each = 3 pts

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. Biology The area of science that studies living organisms. –“bio” = life/ living –“ology” = the study of

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. Genetics The area of science that studies heredity.

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. Heredity – p. 56 The passing of traits from parents to offspring.

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. Characteristic – p. 58 A feature that has different forms in a population. example: hair color

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. Traits – p. 58 The different forms of the feature example: brown or red hair

14. Characteristics vs. Traits Characteristics Traits Hair Color Red or Blonde Brown Black

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. Dominant Trait-- p. 59 The trait observed in the first generation when parents that have different traits are bred.

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. Recessive Trait –p. 59 A trait that reappears in the second generation after disappearing in the first generation when parents with different traits are bred.