What is a gene ?

2. What is a gene? Section of a DNA molecule that contains the information to code for a specific protein

3. An individual who has two different alleles for a trait _Hybrid or hetereozygous_________.

4. If an allele for a specific trait is not completely dominant over the other allele it is called? Incomplete dominance

5. A striped fruit fly is crossed with a non-striped fly. N = non-striped is dominant n = striped is recessive What is the genotype of the striped parent? nn

6. A striped fruit fly is crossed with a non-striped fly. All 100 offspring are non-striped. N = non-striped is dominant n = striped is recessive What is the genotype of the non-striped parent? NN

7. What is an allele? Different forms of a gene

8. An individual who has two identical alleles for a gene is ___purebred_______ .

9. What does it mean if an allele is dominant? It is the one whose trait always shows up in the organism when the allele is present

10. Why do some of the offspring of 2 hybrid individuals show the recessive form of the trait? The hybrid parents each had one recessive gene hidden

11. The ‘B’ gene controls the color of a dog’s coat. The ‘R’ gene controls the texture. Which traits would occur in the following offspring? bbRR White fur & rough texture

12. What types of cells are produced by meiosis? Sex cells

13. During meiosis, the chromosome pairs separate into two different cells. The sex cells that form later have only _____as many chromosomes as the other cells in the organism . ½ (half)

14. Each skunk body cell has 50 chromosomes. How many chromosomes will each skunk sex cell have? 25

15. State 1 advantage for sexual reproduction and 1 advantage for asexual reproduction. Sexual reproduction can producce new combinations of DNA Asexual reproduction one parent can quickly provide many identical offspring

16. Consider the following statement: “Organisms that reproduce asexually are at a higher risk of extinction than organisms that reproduce sexually. Do you agree or disagree? Explain your answer. Organisms from asexual reproduction have no genetic variation and may not survive changes in environment

17. In a heterozygous individual, the ______dominant____ allele determines the phenotype.

18. For a particular plant, leaf texture is ether fuzzy or smooth. A purebred fuzzy plant is crossed with a purebred smooth plant. All offspring are smooth. Which one is dominant? How do you know?___smooth ____.

19. Mendel crossed 2 pea plants: one with green pods and one with yellow pods. The F1 generation all had green pods. What color pods will the F2 generation have? Most F2 will be green but some will be yellow

20. A child has a genetic disease caused by a single gene. Neither parent has the disease. The allele that causes the genetic disease is ____recessive______.

21. Suppose a white kitten with a tiger pattern and an orange kitten with a tiger pattern are both in the mother’s litter. Can you describe what you think the kitten’s father looks like? Explain. Father may have white fur or orange fur or both

22. A daughter inherits a. more genes from her mother b. more genes from her father c. one copy of each gene from her mother and one copy from her father C

23. A man who is heterozygous for the albino allele is married to a woman who is homozygous for normal skin color (Aa x AA). What fraction of their children would you expect to be albino? 0/4

24. In horses, the allele for black coat (B) is dominant over the allele for a brown coat (b). A cross between a black horse and a brown horse produces a brown coat. Is the black horse hybrid or purebred? hybrid

25. In guinea pigs, the allele for smooth coat (S) is dominant over the allele for a rough coat (s). Explain how you could find out whether a guinea pig with a smooth coat is hybrid or purebred.Cross smooth coat pig with rough coat pig all rough=hybrid, all smooth=purebred

26. What is the probability that a cross between a hybrid pea plant with round seeds and one with wrinkled seeds will produce offspring with wrinkled seeds?__1/2 or 50%_.