The darkest part of a shadow where no light falls at all is called the penumbra region.

Umbra is the darkest part of a shadow.

The light falling on the mirror is called ____ ray.

The part of decidua where placenta is formed is called

State which of the following statements are true and which are false : A diameter of a circle divides the circular region into two parts, each part is called a semicircular region.

The region around a magnet where its influence is felt is called magnetic field.

A source of light of wavelength 5000Å is placed as shown in figure. Considering interference of direct and reflected rays, determine the position of the region where the fringes will be visible and calculate the number of fringes. .

Human skin colour is believed to be controlled by at least three seprate genes. (a) What do you call this type of inheritance? (b) Suppose the genes are designated as A, B and C and darkness is dominant over fairness, what shall be the genotypes of the darkest, fairest and intermediate skin colour? (c) What will be the total number of allele combinations in the gametes of a person heterozygous for all the three genes?

What is the region of a shadow that receives some light from the source and gets partially illuminate called?

Draw a vertical section of the human eye and label any six of those parts only through which the light rays pass and fall on the retina.

Name the following : That part of the chloroplast where the light reaction of photosynthesis takes place.