Answer the following:
Disease in which the skin becomes pale, hairs are while and eyes are usually pink due to absence of melanin pigment in the retina and sclera.

Name the following Genetic disorder in which skin becomes pale, hairs are white and eyes are usually pink.

Answer the following in one sentence : Which disease is caused due to deficiency of iodine ?

Name the following Brown pigment that gives colour to our eyes, skin and hair.

Paragraph based questions : Read the following paragraph and answer, the questions based on it. The presence or absence of organs is the first criterion for classification of plants. The presence or absence of separate conducting tissues for conduction of water and food is the next consideration for classification. Do the plants bear seeds? If they do then, whether the seeds are enclosed in a fruit or not is also an important criterion for classification. Finally, plants are grouped depending upon the number of cotyledons in the seeds. In 1883, Eichler, a botanist, classified the Kingdom Plantae into two sub-kingdoms. As a result, two sub-kingdoms, cryptogams and phanerogams were considered for plant classification. Which criteria are taken into account while classifying the lower groups of the plants?

In the modern periodic table, the elements are arranged in the increasing order of their atomic number. This arrangement is based on the modern periodic law, which states that the properties of elements are a periodic function of their atomic numbers. In the modern periodic table, each column is called a group and each row is called a period. Elements within the same group show similarity and gradation in properties. This is due to the same number of electroms in the outermost shell . Based on the above paragraph, answer the following question: What is the trend in the variation of valency while going down a group?

Lichen is usually cited as an example of symbiosis in plants where an algal and a fungal species live together for their mutual benefit. Which of the following will happen if algal and fungal partners are separated from each other? Both will survive and grow normally and independent from each other. both will die. Algal component will survive while the fungal component will die. Fungal component will survive while the algal partner will die. Based on your answer how do you justify this association as symbiosis.