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#Question id: 16125

You are studying regulation of the yeast enzyme glutamine synthetase (GS), which is encoded by the GLN1 gene. You have isolated two mutants, designated gln2– and gln3–, that give decreased GS activity. Mating of either gln2– or gln3– haploids to wild type produces heterozygous diploids that show normal amounts of GS expression. When you cross either a gln2– or gln3– haploid to a gln1– strain the resulting diploids show normal expression of GS.              
From these experiments,  Classify  the  gln2– and gln3– mutations in terms of their basic genetic properties explaining the rationale behind your conclusions. Based on these properties make a proposal for the types of regulatory functions affected by the gln2– and gln3– mutations.

#Unit 13. Methods in Biology
  1. Both are uninducible, as they give decreased glutamine synthetase (GS) activity
    Both are recessive, as mating them with wild type produces normal GS activity
  2. Both are inducible, as they give decreased glutamine synthetase (GS) activity
    Both are dominant, as mating them with wildtype produces normal GS activity.
  3. gln3– are inducible while gln2–are uninducible, as they give decreased glutamine synthetase (GS) activity  
    only gln2– are recessive, as mating them with wildtype produces normal GS activity.
  4. gln3– are uninducible while gln2–are inducible, as they give decreased glutamine synthetase (GS) activity  
    only gln3– are recessive, as mating them with wildtype produces normal GS activity.

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TLS Online TPP Program

#Question id: 7273

#Unit 5. Developmental Biology

Hox9 and Hox10 paralogues specify the stylopod, Hox11 paralogues specify the zeugopod, and Hox12 and Hox13 paralogues specify the autopod. This scenario has been confirmed by numerous experiments.

Which of the following experiment correctly describe this scenario?
TLS Online TPP Program

#Question id: 7274

#Unit 5. Developmental Biology

The following experiment is designed to study the role of several hormones in the regulation of metamorphosis in frogs.

Group #

Treatment

Days to Metamorphosis

1

Saline

30

2

Prolactin

> 100

3

TSH

15

4

Thyroxine

10

5

Corticosterone

30

6

Thyroxine + Corticosterone

5

7

Prolactin + TSH

30

8

Thyroid gland removed

> 100

 If the thyroid gland were removed from the tadpoles in Group 3, metamorphosis would
TLS Online TPP Program

#Question id: 7275

#Unit 5. Developmental Biology

The following experiment is designed to study the role of several hormones in the regulation of metamorphosis in frogs.

Group #

Treatment

Days to Metamorphosis

1

Saline

30

2

Prolactin

> 100

3

TSH

15

4

Thyroxine

10

5

Corticosterone

30

6

Thyroxine + Corticosterone

5

7

Prolactin + TSH

30

8

Thyroid gland removed

> 100

 

If the thyroid gland were removed from the tadpoles in Group 4, metamorphosis would
TLS Online TPP Program

#Question id: 7276

#Unit 5. Developmental Biology

The cells that make up a tetrapod limb arise from three developing tissues:

The ____a______ will provide skeletal precursors to the limb.

The _____b____ will provide muscle precursors to the limb.

The _____c____ will provide the skin of the limb.

Which of the following option is correct?
TLS Online TPP Program

#Question id: 7277

#Unit 5. Developmental Biology

According to this model, Which of the following statements are correct?
TLS Online TPP Program

#Question id: 7278

#Unit 5. Developmental Biology

The following demonstrates the blastocoel formation in the mammals. Which of the following statement is correct?