2. Mendel is known as the _________________________ 1. Who is Gregor Mendel? An Austrian monk who disproved the idea of “blended inheritance” more than 150 years ago. “Father of Genetics” 2. Mendel is known as the _________________________
3. Why did Mendel study pea plants? 1. They reproduce quickly. Many plants = lots of data 2. Easily observable traits, such as flower color and pea shape 3. Mendel could easily control plant reproduction
4. Explain what happened during Mendel’s first generation crosses (p Purple x Purple = White x White = Purple x White (both true-breeding) = All purple All white All purple
5. When Mendel bred a true-breeding purple and a true-breeding white plant he got all purple offspring. Is this what you would have expected? Why or why not? Most people would probably expect to have half purple and half white flowers. Most would not expect to have no white flowers at all!
Purple and white offspring! 6. Explain what happened during Mendel’s second generation crosses (See page 393) a. Purple hybrid x Purple hybrid = Purple and white offspring!
7. By studying pea plants Mendel was able to determine that some traits are _____________ while others are blocked or _________________. dominant recessive
Define: 8. Heredity - 9. Genetics - The passing of traits from parents to offspring The study of how traits are passed from parents to offspring
A genetic factor that blocks another genetic factor 10. Dominant Trait – 11. Recessive Trait - A genetic factor that blocks another genetic factor A genetic factor that is blocked by the presence of a dominant factor
children are not a perfect mixture of their parents’ traits! Do an organism’s characteristics and traits mix (like colors of paint) to resemble both their parents? Explain. Usually No, children are not a perfect mixture of their parents’ traits!
______________ is the passing of traits from parents to offspring, while _______________ is the study of how traits are passed from parents to offspring. Heredity Genetics
Mendel’s Experimental Methods Pollination in pea plants can occur through both _______-pollination and ________-pollination self cross
What is cross-pollination? When pollen from one plant reaches the pistil of a flower on a different plant.
What is self-pollination? When pollen from a flower pollinates the same flower or another flower in the same plant.
Which type of pollination? Cross-pollination Self-pollination
List the 4 main steps of Mendel’s cross-pollination technique (page 391) 1. Mendel removed the stamens from the purple flower. 2. He transferred pollen from the stamens of the white flower to the pistil of the purple flower. 3. The pollinated pistil of the purple flower grew into a pea pod. Then Mendel planted the peas. 4. The peas grew into plants.
Add to notes: not in packet True-breeding – has genes for the same trait B= brown, b= blue (example: BB, bb) Hybrid – has different genes for the same trait (example: Bb)
When a true-breeding plant self-pollinates, it always produces offspring with traits that __________________ (page 391) match the parent
Hybrid plants came from true-breeding parent plants with different ________________________ (page 393) forms of the same trait
Look at page 394. What traits are dominant?? When Mendel crossed two hybrids for a trait, the trait that had disappeared then reappeared in a ratio of _____. 3:1 Look at page 394. What traits are dominant??
Mendel’s Conclusions (page 395) 2 Mendel concluded that ______ genetic factors control an inherited trait. When organisms reproduce each reproductive cell contributes _____ factor for each trait. 1
3. Mendel hypothesized that in hybrid crosses the purple factor in pea plants is the only factor seen or expressed because it blocks the white factor. This means that the purple trait is ______________ , while the white trait is ________________. 4. A recessive trait is only observed when __________________________ are present. dominant recessive two recessive genetic factors
5. In a second generation of pea plant hybrids, about ______ percent of the plants had purple flowers. This means that plants had at least _______ dominant factor. Twenty-five percent of the second generation plants had _________ flowers, which means these plants had ______ recessive factors. 75 one white two
Read page 397 and answer the following questions. Other than a monk and scientist, Mendel was also a ______________________. What year was human DNA completely mapped? ________________ What two scientists discovered the structure of DNA molecules? ______________________ Gardener and Beekeeper 2003 Francis Crick and James Watson
Inherited Traits Inventory What are YOUR visible traits??
Do you have detached earlobes?? What is your phenotype??? Do you have detached earlobes??
I have a hitchhiker’s thumb
Can you roll your tongue??
Do you have dimples?
Are you right-handed?
Do you have freckles?
Do you have naturally curly hair?
Do you have a cleft chin?
Do you have allergies?
Do you have a widow’s peak?
Do you cross your left thumb over your right thumb?
Can you see the colors red and green?
I have brown eyes
I have mid-digital hair
My second toe is longer than my big toe
Can you taste P.T.C.?
Answer follow-up questions on back!! Interview 5 Family Member (in person or over the phone) and get signatures!! Answer follow-up questions on back!! DUE: Next Monday!!