1. A species of insect has either long or short wings
A species of insect has either long or short wings. Scientists suspect there is a dominant-recessive relationship between these two traits. A scientist crosses two insects with short wings and sees that most of the offspring resulting from the cross have short wings, but some have long wings. –Explain how to tell which trait is dominant. 9 8 10 20
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2. You can tell the trait for short wings is dominant because most of the offspring have short wings. Some of these are pure dominant and some are a combination of the traits. Both combinations would have short wings.

3. A species of insect has either long or short wings
A species of insect has either long or short wings. Scientists suspect there is a dominant-recessive relationship between these two traits. A scientist crosses two insects with short wings and sees that most of the offspring resulting from the cross have short wings, but some have long wings. –Explain whether each of the following are pure for the trait or whether they have a combination of traits: –The two parent insects –The offspring with long wings –The offspring with short wings 9 8 10 20
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4. The offspring with long wings would have to be pure, because they show the recessive trait. The parents must have a combination of the traits because they show the dominant trait, but have offspring that show the recessive trait.

5. Species that reproduce sexually have an advantage over those that reproduce asexually when external conditions change. This is how organisms have become adapted to their environment over time. – Describe the difference between sexual and asexual reproduction in terms of the genetic makeup of the offspring. 9 8 10 20
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6. Sexual reproduction uses genetic material from two parents to produce offspring with unique sets of traits. Asexual reproduction produces offspring with the same combination of traits as the parent.

7. Explain why a species that reproduces sexually might be more likely to survive a sudden environmental change than a species that reproduces asexually. 9 8 10 20
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8. In a changing environment, a sexually reproducing species is likely to have a diverse set of individuals in its population. Although some individuals may not survive, others may have a combination of traits that helps them to survive

9. Offspring inherit genetic traits from their parents
Offspring inherit genetic traits from their parents. These traits are passed on to the offspring in the genetic material from each parent. Many genes that cause these traits have dominant and recessive forms. – Under what conditions does an individual express a dominant trait from its parents? – Under what conditions does an individual express a recessive trait from its parents? 9 8 10 20
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10. An individual will express a dominant trait if it inherits a dominant gene from at least one of its parents. It will express the recessive trait only if it inherits the recessive form of the gene from both of its parents.