Which of the following pairs is $wrongly$ matched?
Starch synthesis in pea : Multiple alleles
T .H. Morgan : Linkage
$XO$ type sex determination : Grasshopper
$ABO$ blood grouping : Co-dominance
Choose correct answer :
$(i)$ Queen Elizabeth shows a number of haemophilic descendents.
$(ii)$ Variation in blood group prevalences due to incomplete dominance.
$(iii)$ Drosophila has three pairs of autosomal chromosomes.
$(iv)$ In birds, female is heterozygous.
Which of the following characteristics represent ‘Inheritance of blood groups’ in humans?
$(a)$ Dominance
$(b)$ Co-dominance
$(c)$ Multiple allele
$(d)$ Incomplete dominance
$(e)$ Polygenic inheritance
What is the correct sequence of the following events
$1.$Formation of the chromosome theory of heredity
$2.$Experiments which proved that $DNA$ is the hereditary material
$3.$Mendel's laws of inheritance-discovery
Code :
Match the terms in column $I$ with their description in column $II$ and choose the correct option.
Column $-I$ | Column $-II$ |
$(A)$ Dominance | $(i)$ Many genesgovern a single character |
$(B)$ Codominance | $(ii)$ In a heterozygousorganism only one allele expresses itself |
$(C)$ Pleiotropy | $(iii)$ In a heterozygousorganism both alleles express themselves fully |
$(D)$ Polygenic | $(iv)$ A single gene inheritanceinfluences many characters |
Pick out the correct statements.
$(1)$ Haemophilia is a sexlinked recessive disease.
$(2)$ Down’s syndrome is due to aneuploidy.
$(3)$ Phenylketonuria is an autosomal recessive gene disorder.
$(4)$ Sickle cell anaemia is an $X$-linked recessive gene disorder.