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#Question id: 16140


Many mouse genes are “tissue-specific,” that is, they are present throughout the body but are expressed in only one of the animal’s many tissue types. (Other mouse genes are expressed throughout the body, or in multiple tissues.) Geneticists can study the regulation of a mouse gene by fusing the gene’s promoter region to the LacZ coding sequence and injecting the construct to create a transgenic mouse. Fusion of the mouse amylase promoter to LacZ yielded a Pamylase-LacZ construct.
You are surprised to observe that mice homozygous for the transgene insertion display a serious heart defect. (Heterozygotes have normal hearts.) which one is a  possible explanation?
a) LacZ overexpression (with two copies of the transgene) causes the defect.
b) the insertion disrupted a gene that is haploinsufficient.
c) the insertion disrupted a gene that is haplosufficient.
d) LacZ expression inhibition (with two copies of the transgene) causes the defect.
Which of the following statements is correct  predict about the  heart defect?

#Unit 13. Methods in Biology
  1. A and C
  2. C and D
  3. A and B
  4. B and D
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TLS Online TPP Program

#Question id: 3273

#Unit 11. Evolution and Behavior

The number of forward mutations is equal to the number of reverse mutations then

a) Population is in equilibrium for forward and reverse mutation rates

b) The population is being in Hardy–Weinberg equilibrium

c) No further change in allelic frequency

TLS Online TPP Program

#Question id: 3274

#Unit 11. Evolution and Behavior

The common edible frog of Europe is a hybrid between two species, Rana lessonae and Rana ridibunda. The hybrids were first described in 1758 and have a wide distribution, from France across central Europe to Russia. Both male and female hybrids exist, but when they mate among themselves, they are rarely successful in producing offspring. What can you infer from this information?

TLS Online TPP Program

#Question id: 3275

#Unit 11. Evolution and Behavior

When imbalances occur in the sex ratio of sexual species that have two sexes (that is, other than a 50:50 ratio), the members of the minority sex often receive a greater proportion of care and resources from parents than do the offspring of the majority sex. This is most clearly an example of ________.

TLS Online TPP Program

#Question id: 3276

#Unit 11. Evolution and Behavior

Which of these conditions are always true of populations evolving due to natural selection?

Condition 1: The population must vary in traits that are heritable.

Condition 2: Some heritable traits must increase reproductive success.

Condition 3: Individuals pass on most traits that they acquire during their lifetime.

TLS Online TPP Program

#Question id: 3277

#Unit 11. Evolution and Behavior

Which of the following describes the most likely order of events in allopatric speciation?

TLS Online TPP Program

#Question id: 3278

#Unit 11. Evolution and Behavior

What does the biological species concept use as the primary criterion for determining species boundaries?