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#Question id: 5141

Which of the following statement not describe the concept of morphogenetic gradient?

#Unit 5. Developmental Biology

  1. Three genes involved in determining the proximal-distal axis of the drosophila’s leg. In the third instar leg disc, the center of the disc secretes the highest concentration of two paracrine factors Wingless and Decapentaplegic. High concentrations of these paracrine factors induce expression of the Distal-less gene. Moderate concentrations induce the expression of the dachshund gene, and lower concentrations induce the expression of the homothorax gene.

  2. Once inside the oocyte, bicoid mRNA attaches to dynein proteins that are maintained at the microtubule organizing center (the slower growing “minus end”) at the anterior of the oocyte. About 90% of the bicoid mRNA is localized to the anterior 20% of the embryo, with its concentration peaking at 7% egg length.

  3. In the anterior region, Bicoid protein prevents translation of the caudal message to specify head and thorax structures, while in the posterior region, nanos protein prevents translation of the hunchback message to specify abdomen.

  4. In the frog Xenopus laevis the specification of different mesodermal cell types by activin. At high concentrations, activin induced expression of the goosecoid gene to specify dorsal most structures, at slightly lower concentrations of activin the same tissue activated the Xbra gene and was specified to become muscle. At still lower concentrations, these genes were not activated, and the “default” gene expression instructed the cells to become blood vessels and heart.

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#Question id: 3374

#Unit 11. Evolution and Behavior

Consider an autosomal locus with two alleles A1 and A2 at frequencies of 0.6 and 0.4 respectively. Each generation, A1 mutates to A2 at a rate of μ = 1 x 10-2 while A2 mutates to A1 at a rate of υ = 1 x 10-1) Assume that the population is infinitely large and no other evolutionary force is acting. The overall change in allelic frequency will be
TLS Online TPP Program

#Question id: 3375

#Unit 11. Evolution and Behavior


Evolutionary force

Caused

A

Mutation

i

Increase genetic variation within population 

B

Genetic Drift

ii

Decrease genetic variation within population 

C

Migration 

iii

Decrease genetic variation between  population 

iv

Increase genetic variation between population 

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

#Question id: 3376

#Unit 11. Evolution and Behavior

The frequencies of two allele’s p and q for a gene locus in a population at Hardy-Weinberg equilibrium are 0.6 and 0.4, respectively. After a few generations of inbreeding, the heterozygote frequency was found to be 0.10, The inbreeding coefficient in this case is
TLS Online TPP Program

#Question id: 3377

#Unit 11. Evolution and Behavior

To call a behavior altruistic, an evolutionary biologist will have to demonstrate that

A) These behavior is decrease the individual fitness of the donor and increases the individual fitness of the recipient

B) These behavior is increases the individual fitness of both the donor and the recipient

C) Overall increase the inclusive fitness of the population

D) These behavior depend on genetic relation

Which of the following above statement is correct?
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#Question id: 3378

#Unit 11. Evolution and Behavior

Following certain conditions is present in a population?

A- Large Population

B- Each locus follows complete dominance

C- No reproductive advantage

D- No migration

E- No linkage between genes

Which of the following above condition allowed to validity of Hardy- Weinberg Prediction?
TLS Online TPP Program

#Question id: 3379

#Unit 11. Evolution and Behavior

polymorphism is define existence of two or more form of same species within same population at the same time and place .polymorphism either balanced or transient depending upon type of natural selection  which of the following reason for balanced genetic polymorphism

a. each morph has selective advantage at equal intensity

b. non of the morph has selective advantage over other

c. heterzygote superiority