Although some species differences exist, the process of primary neurulation is relatively similar in all vertebrates. Primary neurulation can be divided into four distinct but spatially and temporally overlapping stages:

A. Bending of the neural plate

B. Closure of the neural tubeC. Elongation and folding of the neural plate D. Convergence of the neural folds

C. Elongation and folding of the neural plate

D. Convergence of the neural folds

What is the correct sequence?

#Question id: 4895

#Unit 8. Inheritance Biology

What is the difference between a linkage map and a physical map?

a) Genetic maps are based on recombination frequencies, but physical maps are based on restriction digestion.

b) Physical DNA map describes the absolute position of genes on a chromosome while genetic map so variable

c) Genetic maps are important to identify the origin of diseases, whether they are inherited or arise due to a random mutation.

#Question id: 4896

#Unit 8. Inheritance Biology

A cross between individuals with genotypes AaBbX aabb produces the following progeny:

AaBb -  21, aaBb- 83, Aabb-   77,  aa bb -19

Which of the following statements is true?

a) Map unit between gene A and B

b) Configuration

c) parents genotype of AaBb

#Question id: 4897

#Unit 8. Inheritance Biology

When two independent pure lines AAbb and aaBB of pea with white flowers are crossed, the F1 progeny has purple flowers. Gene A and B link at 20 map unit. The following conclusions were made

A. When an heterozygous individual of the genotype AaBb is test crossed, progenies with purple and white in a ratio of 1:3

B. When an heterozygous individual of the genotype AaBb is test crossed, progenies with purple and white in a ratio of 1:9

C. This is an example of complementary gene action

D. The F2 progeny obtained on selfing shows both pruple and white flower in a ratio of 9:7                                            

Which of the following conclusions are correct?

#Question id: 4898

#Unit 8. Inheritance Biology

A three point test cross was carried out in Drosophila melanogaster involving three adjacent genes A, B and C. arranged in the same order. The distance between A to B is 15 map unit (mu) and that between B to C is 30 map. The coefficient of coincidence = 0.67. What is the percentage of double recombinants in the progeny obtained from the testcross?

#Question id: 4899

#Unit 8. Inheritance Biology

In Neurospora a cross between the genotypes 'A' and 'a' results in an ascus with ascospores of genotypes as shown below: 

 Statements A to D are events that could have occurred during meiosis.

A) Class I is results of no crossing over between the centromere and gene.

B) Class II is results of single crossing over between the centromere and gene

C) Class I shows segregation of alleles 'A' and 'a' in meiosis II

D) Class II shows segregation of alleles 'A' and 'a' in meiosis II

#Question id: 12693

#Unit 8. Inheritance Biology