Which one of the following is an example of polygenic inheritance?
Flower colour in Mirabilis jalapa
Production of male honey bee
Pod shape in garden pea
Pod shape in garden pea
Sertoli cells are regulated by the pituitary hormone known as
FSH
GH
Prolactin
Prolactin
In Mendel's experiments with garden pea, round seed shape (RR) was dominant over wrinkled seeds (rr), yellow cotyledon (YY) was dominant over green cotyledon (yy). What are the expected phenotypes in the F2 generation of the cross RRYY x rryy?
Only round seeds with green cotyledons
Only wrinkled seeds with yellow cotyledons
Only wrinkled seeds with green cotyledons
Only wrinkled seeds with green cotyledons
One gene – one enzyme hypothesis was postulated by
R. Franklin
Hershey and Chase
A. Garrod
A. Garrod
Test cross involves
crossing between two genotypes with recessive trait
crossing between two F1 hybrids
crossing the F1 hybrid with a double recessive genotype
crossing the F1 hybrid with a double recessive genotype
Antiparallel strands of a DNA molecule means that
one strand turns anti-clockwise
the phosphate groups of two DNA strands, at their ends, share the same position
the phosphate groups at thestart of two DNA strands are in opposite position (pole)
the phosphate groups at thestart of two DNA strands are in opposite position (pole)
Mast cells secrete
hippurin
myoglobin
histamine
histamine
C.
histamine
Histamine is a protein, acting as a vasodilator (widening of blood vessels) in inflammatory and allergic reactions and also increases the permeability of small vessels. It is secreted from the mast cells which widely occur in the aerolar connective tissue.
Two other active substances secreted by mast cells are Heparin, a proteoglycan, which prevents coagulation of blood vessels and serotonin, a protein, which acts as vasoconstrictor to stop bleeding and to increase blood pressure.
If a colourblind woman marries a normal visioned man, their sons will be
all normal visioned
one-half colourblind and one-half normal
three-fourths colourbling and one-fourth normal
three-fourths colourbling and one-fourth normal
Restriction endonuclease
cuts the DNA molecule randomly
cuts the DNA molecule at specific sites
restricts the synthesis of DNA inside the nucleus
restricts the synthesis of DNA inside the nucleus