| A | B |
|---|
| How many chromosomes are shown in a normal human karyotype? | 46 |
| In humans, a male has _____ | one X and one Y chromosome |
| Human females produce egg cells that have ____ | one X chromosome |
| In a pedigree, a circle represents ____ | a female |
| A pedigree can be used to _____ | determine whether a trait is inherited. |
| A _____ can be used to show how a trait is passed from one generation to the next. | pedigree |
| Using a pedigree you can determine whether _____ | an allele is dominant or recessive |
| PKU is an autosomal recessive disorder, so a person who has PKU _____ | inherited the allele for the trait from both parents |
| Most sex-linked traits are located on _____ | the X chromosome only |
| Colorblindness is more common in males than in females because _____ | the allele for colorblindness is recessive and located on the X chromosome |
| Because the X chromosome contains genes that are vital for normal development, no baby has been born _____ | without X chromosomes |
| ____ is the combination of sex chromosomes that represents a female. | XX |
