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#Question id: 7102

How is the Spemann organizer distinguished from the other mesodermal cells during induction by the cells of the vegetal region?

#Unit 5. Developmental Biology
  1. The cells of the Spemann organizer become different as they pass over the dorsal lip of the blastopore during gastrulation.
  2. Beta-catenin, which has become localized to the nucleus in the Nieuwkoop center as a result of cortical rotation, turns on high levels of the TGF- signalling molecule, Nodal, and this relatively high level distinguishes the adjacent cells of the Spemann organizer from the rest of the mesoderm.
  3. The Spemann organizer is formed from cells of the Nieuwkoop center, which have migrated upward in the embryo.
  4. BMP-4 signalling from ventral mesodermal cells toward the dorsal region specify the dorsal-most cells as organizer.
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TLS Online TPP Program

#Question id: 29108

#Unit 8. Inheritance Biology

If 3 genes are unlinked which is X, Y and Z, the probability of progeny being X+ X-Y+Y- Z- Z- from a cross between  X+X+Y+Y-Z+Z- and X-X-Y+Y+Z-Z- parents will be____
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#Question id: 29109

#Unit 8. Inheritance Biology

If the probability of being blood types are;
Blood type A = 1/4
Blood type B = 3/4
Blood type O = 1/2
what is the probability of being either blood-type A  or blood-type B ?
TLS Online TPP Program

#Question id: 29110

#Unit 8. Inheritance Biology

When two parents heterozygous for albinism mate (Aa X Aa), the probability
of their having a child with albinism (aa) is 1/4 and the probability of having a child with normal pigmentation (AA or Aa) is 3/4 . What is the probability of this couple having 5 children, two with albinism and three with normal pigmentation?
TLS Online TPP Program

#Question id: 29111

#Unit 8. Inheritance Biology

A plant with purple flowers is crossed with a plant with white flowers, and the F1 are self-fertilized to produce 105 F2 progeny with purple flowers and 45 with white flowers.
A scientist hypothesized that there are two genes with identical functions that control the dominant trait. The scientist also proposed that the two genes are not linked. The scientist carried out a chi-square test to test the hypothesis. Which one of the following options is the correct chi-square value obtained by the scientist?
TLS Online TPP Program

#Question id: 29112

#Unit 8. Inheritance Biology

An example of multiple alleles is at a locus that determines the feather pattern of mallard ducks. One allele, M, produces the wild-type mallard pattern, MR, produces restricted, and a third allele, md, produces dusky. In this allelic series, dominancy shows MR >M > md
If a cross between  MR md X M md, What proportion of progeny will be restricted?
TLS Online TPP Program

#Question id: 29114

#Unit 8. Inheritance Biology

Given below, is the result of a complementation test for six independent mutants (1 to 6)