Chapter 7. Animation Activity: Determining Gene Order by Three-Point Cross

After you've completed the activity, click the button below to answer questions about what you've learned.

Animation Assessment

Question

J7Nf6wIAprluCcHb3ffL3V96NgBljCCfmbx8a8k36gLR+0o9YIosnBnzoGXbvfyqG0MQmeCYmH47sLvnvRt2i38ZCl3jeYu+nK99cm6bB0KyVJMqLLbLjtH0WGSwawZW+oHhbRLdkNGDTwCmRx1KzdoFat0CQrSb5C6SRj+vInaYth/h2ucBqzL7D+6/s6cTsh0YWmhyR8pfum1un2tlBzk1TgSvQDWaH/yKjOydREUtuTq703+gjWL1YjEhrLBIZDHDtx6kXD8VvCEl
2
Correct.In the absence of recombination the wild-type female parent can only pass on one of her two homologous chromosomes to each gamete. Since she is heterozygous for all three mutations, her homologous chromosomes are not identical. Therefore she can produce two different types of gametes.
You have one more chance to answer the question correctly. Try again.
Incorrect. In the absence of recombination the wild-type female parent can only pass on one of her two homologous chromosomes to each gamete. Since she is heterozygous for all three mutations, her homologous chromosomes are not identical. Therefore she can produce two different types of gametes.

Question

wq2Q0Sgq0P2hAJCs9BYBioQNYu0PIJD3xySOOTIoX/v/Ic1z7i+Zp4rki1KBTXTCyAZ7d4TgV5PJbLSu61wQFs7PzsYZnrapQLhQKMKSU4ayYYtdQY/516YryB6xf7QxpyNIz1OtCtSr2Uk2UUZ8e97chCbPuo0xIQLuXDFK3l7zPC/K+imFeT7ruuL+ao/vKka9utIsdMYfZQw2Rou3vRRbQqao2792MYRHWs0s5vCwwJL0yvU5erLoADiVTfcl
2
Correct. In the wild-type, triple-heterozygous female parent, there are eight different types of gametes possible. Two of these are non-recombinant (no crossing over) and the other six are recombinant (produced by cross over between scarlet and spineless, cross over between spineless and ebony, and double cross over).
You have one more chance to answer the question correctly. Try again.
Incorrect. In the wild-type, triple-heterozygous female parent, there are eight different types of gametes possible. Two of these are non-recombinant (no crossing over) and the other six are recombinant (produced by cross over between scarlet and spineless, cross over between spineless and ebony, and double cross over).

Question

uLGZhLAOAnYh0EhAOWrWIQtGdpkErXtAFyK9l8vle/I/gbRWsCyJhCaeGtHfw8Xy2MJaJi4pq/pasttdwFt9L0FHdkpD5e0fn+I9Sm50tXmkiYGEAmZFrD3mJl8CKs++zkeGmwHmszupQ1P5R7j8/6CXWLqF0TKh3SI4ztF2+1sUxG90OjZoVUnxirTHQjVC
2
Correct. The triple-mutant male parent is homozygous for all three mutations. Since scarlet, spineless and ebony mutations are all on chromosome 3 and both homologous chromosomes contain all three mutations, only one type of gamete can be formed.
You have one more chance to answer the question correctly. Try again.
Incorrect. The triple-mutant male parent is homozygous for all three mutations. Since scarlet, spineless and ebony mutations are all on chromosome 3 and both homologous chromosomes contain all three mutations, only one type of gamete can be formed.

Question

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
2
Correct.The most common progeny in a three-point test cross represent those arising from non-recombinant gametes in the triple-heterozygote parent. If the scarlet and spineless mutations are coupled, these two mutations will segregate together on a non-recombinant gamete and the ebony mutation will segregate separately on the other non-recombinant gamete since ebony is in repulsion.
You have one more chance to answer the question correctly. Try again.
Incorrect. The most common progeny in a three-point test cross represent those arising from non-recombinant gametes in the triple-heterozygote parent. If the scarlet and spineless mutations are coupled, these two mutations will segregate together on a non-recombinant gamete and the ebony mutation will segregate separately on the other non-recombinant gamete since ebony is in repulsion.

Question

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
2
Correct. The least common progeny in a three-point test cross represent those arising from the double cross over gametes in the triple-heterozygote parent. In the original animation, spineless locus is between the scarlet and ebony locus. Therefore, if the scarlet and spineless mutations are coupled and the ebony mutation is repulsed, the double cross over gametes are those containing only the ebony and spineless mutations and those containing only the scarlet mutation.
You have one more chance to answer the question correctly. Try again.
Incorrect. The least common progeny in a three-point test cross represent those arising from the double cross over gametes in the triple-heterozygote parent. In the original animation, spineless locus is between the scarlet and ebony locus. Therefore, if the scarlet and spineless mutations are coupled and the ebony mutation is repulsed, the double cross over gametes are those containing only the ebony and spineless mutations and those containing only the scarlet mutation.

Question

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
2
Correct. In a three-point test cross, the triple-heterozygote can always theoretically produce eight different kinds of gametes (2 non-recombinant or parental types and six recombinant types) which should result in eight phenotypic classes. The double cross over recombinants are always the least frequent type of gamete produced. Therefore, if only six types of progeny are represented in the offspring, the missing two phenotypes can be assumed to be those that would have resulted from double cross over gametes.
You have one more chance to answer the question correctly. Try again.
Incorrect. In a three-point test cross, the triple-heterozygote can always theoretically produce eight different kinds of gametes (2 non-recombinant or parental types and six recombinant types) which should result in eight phenotypic classes. The double cross over recombinants are always the least frequent type of gamete produced. Therefore, if only six types of progeny are represented in the offspring, the missing two phenotypes can be assumed to be those that would have resulted from double cross over gametes.

Question

dUmDbVMHOuW3tgZO89Nn/9Jxy+rnOu0Q45wYMLQCFM8VVW58jHuo8dTrSPmwZnEdlFbr8tgqIq2YgO0fbeeX9uTM6KU6dvgnT2oOukUDKGo/DNxZB/hHt/AvC4y1hWoouc5FyQa5NNIKG4Vq2jCL76aRjE8c0IpmPQ6XoXcaja6E812/iWQOKQfjBHkJOVxEs/v5G3EEwaHinlSXBBdrIY0tv+AmxQ3fmDmESztJS+ejLdbYiP2Nx9Kw/4fCXZib7V7MJ6eh/imKQ6hT09Ec+QzZqajEePbwN8WyR8MdTNcyu1b9Rfsa4BdS8g/pyjT4v8ygC6VXXFHvrh5K41iolfqBUcaFEQocYpGiLB/DMj47x02abRGUWE/nvIgmeAvktuk1V7LqaZc572aBZPydHnOwncB2zhAwWd3UtoQQjL6mmbH85cbkF7bJ6lNjMKEFsCgYfExgMqTFFJM01zCPJKu7CdrX4DfYwLGd8szEwfvGaQ5sMMdsccUcp56e3XOm6CPDcO7rArhORnaltUPIHMj8c/tLApHAgEGOsGXcPMz1xkOigF6XXdkya7gf8msWBq+iAONEltSVYjyyYu0XXJIo/5MecTEG5tuThjt/oYcVvJOGF3fdX3yyNcf1MS4XYn8L0yXsBbGEscX3rmUqhdfP0xhNSFzFBDZ0aTcFL3mKDNRaD+2/E41+QYkBDW8ZwpuXUMmKfBuDGtyzsDNlTxGyhfbxj2UApe8diy3TjcfdzI19384Wqg/7/NaIe04z4hltrrLAIS7zzrxXU2KzAT/WLwCTturAvBNc+7Zb4E2Yf6keRUiWq0lT3MR70gPEA5lSmtiiM22frbeG1u9K/eTq/xv1xkhrJBfzo9gq6Hz+SN1jW/ElA34KiPWnmKv3YFfIe7O0AYMyDRvY5Woir3HI9j0IDVGjedAu4bQ67lFqpOS7+G0FqfhGF86u3VqYVAE5LpDVfV3lt+T2OtTfH66TnvXQnGIla0RnV96oX0/G6Rd9f9os/C0dFoPGFQch84FWlw1RsplSbelkzMIf47e19scPgkVMdHjRzQ==
2
Correct. If the triple-heterozygous, wild-type female were the result of a mating between two true breeding parental stocks, with one parent being scarlet and ebony and the other parent being spineless, scarlet and ebony would be coupled and spineless in repulsion in the wild-type female. This means that the double cross over gametes would be wild-type gametes and triple-mutant gametes. Since the double cross over gametes are the least frequent type of gametes in a three-point test cross, the wild-type and triple-mutant phenotypes will be the least frequent types of progeny.
You have one more chance to answer the question correctly. Try again.
Incorrect. If the triple-heterozygous, wild-type female were the result of a mating between two true breeding parental stocks, with one parent being scarlet and ebony and the other parent being spineless, scarlet and ebony would be coupled and spineless in repulsion in the wild-type female. This means that the double cross over gametes would be wild-type gametes and triple-mutant gametes. Since the double cross over gametes are the least frequent type of gametes in a three-point test cross, the wild-type and triple-mutant phenotypes will be the least frequent types of progeny.