A: Turner's syndrome generally does not occur in males.
R: Foetus with 44 + YO complement generally dies.
Because the absence of X chromosome
A: Sickel cell anaemia occurs due to the point mutation.
R: mRNA produced from Hb(s) gene has GAG instead of GUG.
GUG → Valine GAG →Glutamine
A: Holandric traits are passed from one generation to the next generation.
R: These traits appear more frequently in one sex than in other.
Hoalandric genes are Y linked.
A: Dominance is not an autonomous feature of a gene.
R: It depends as much on the gene product and the production of a particular phenotype from this product.
A: The possibility of a female becoming haemophilic is extremely rare.
R: Mother of such a female has to be carrier and father should be haemophilic.
It is X linked recessive
A: Pseudoalleles are actually closely linked genes.
R: These can be identified easily as both affect different characters, providing separate phenotypes.
These genes occupy different location on a chromosome, but they regulate the same feature.
A: The heterozygotic female for haemophilia may transmit the disease to sons.
R: Such traits show criss-cross inheritance.
A: Non-allosomic genic determination of sex is found in bacteria.
R: Sex is dependent on some environmental factors in prokaryotes.
Sex is regulated by F-plasmid or fertility genes.
A: Crossing over is the exchange of genetic material between non-homologous chromosomes.
R: It produces new linkages.
Exchange of genetic material between homologous chromosome.
A: Mendel gave postulates like "principles of segregation and principles of independent assortment" after studying seven pairs of contrasting traits in garden pea.
R: He was lucky in selecting seven characters in pea that was located on seven different chromosomes.
A: Test cross is the tool for knowing linkage between genes.
R: Monohybrid test cross gives two phenotypes and two genotypes.
A: A recessive mutant pleiotropic gene causes myotonic dystrophy.
R: Gene mutation leads to more synthesis of fibrillin proteins.
A: In snapdragon, F1 plants do not have red or white flowers.
R: It is the intermediate inheritance with neither of the two alleles of a gene being dominant over each other.
Because of incomplete dominance, the allele cannot give its expression completely in figuration.
A: en block inheritance of all genes located on the same chromosome may occur in some organisms.
R: Dihybrid test cross will have only two phenotypes.
A: Morgan's cross III was conducted in Drosophila to locate genes on chromosomes for white eye colour.
R: The cross was done between a red-eyed hybrid female and white-eyed male.
It was a reciprocal cross so white x red eye.
A: Antlers in male deer are sex influenced traits.
R: These are controlled by autosomal genes which are influenced by the sex of bearer.
Antler of deer is the sex-limited feature.
A: One drum stick per nucleus is present in the neutrophil of a normal female.
R: It is absent in the neutrophil of male.
A: Blood group phenotype is controlled by the presence or absence of antigens present on the surface coating of RBC.
R: These antigens are of three types and found in the oligosaccharides rich head regions of a glycophorin.
A: Polyploids with the odd number of chromosomes are propagated vegetatively.
R: Seed formation is absent due to meiotic abnormality.
A: XO type of sex determination is found in a large number of insects.
R: Some of the sperms bear the X-chromosome, whereas some do not.
XX – XO – Type is found in some insects.