Normal colour vision (trichromacy) refers to vision that uses all three types of light cones. People with defected trichromatic vision will be colour blind to some extent and these conditions are called anomalous trichromacy. Three types anomalous trichromacy ( one type of cone perceives light slightly) :
1. Protanomaly – phenotype: reduced sensitivity to red light
2. Deuteranomaly - phenotype: reduced sensitivity to green light
3. Tritanomaly – phenotype: reduced sensitivity to blue
People can also have color blindess as the result of mutation, when loss of function of one cone occurs. This condition is called dichromacy. If there is complete color blindness or monochromacy, the person can’t distinguish any color from grey.
Color blindness is an inherited genetic disorder resulted from mutations on the X chromosome.
B. The levels of classification increased. Previously there were only 2 domains of life, Bacteria and Eukarya, but an additional domain and Kingdom were added when the distinction of Archaea was observed.
The correct answer is option D, Temporal isolation
Temporal isolation is the mechanism which prevents the mating of closely related species living in the same ecosystem. Basically the reproductive barriers prevent these species from interbreeding. Temporal isolation is a prezygotic barrier that causes “time isolation” between the breeding period of two closely related species. The difference in time could be “difference in time of day”, “ difference in season of mating”, “difference in months” and in some cases “ difference in years”.
1. What would happen if a person fell into a black hole?
2. Why it takes more genes to make a tomato than a human.
3. How the placebo effect works.
