Weather, Climate and Adaptations of Animals of Climate — Science STD 7 — Question

What are Milk teeth and permanent teeth?

After we work hard or perform physical activity, we feel hungry. Explain why?

Manya is blindfolded. She is given two unknown solutions to test and determine whether they are acidic or basic. Which indicator should Manya use to test the solutions and why?

Name the end products of anaerobic respiration in yeast.

How water and minerals are transported to leaves from roots?

How does an elephant living in tropical rain forest adapt itself?

A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
(i) What changes do you expect?
(ii) Are these changes chemical in nature?
(iii) Write a word equation for the chemical change, if any.

The process of digestion is a chemical change. Explain.

Consider the following statements
(i) Both acids and bases change colour of all indicators.
(ii) If an indicator gives a colour change with an acid, it does not give a change with a base.
(iii) If an indicator changes colour with a base, it does not change colour with an acid.
(iv) Change of colour with an acid and a base depends on the type of the indicator.
Which of the above statements is/are correct?
(a) Only (iv)
(b) (i) and (iv)
(c) (ii) (iii) and (iv)
(d) All of the above

Write a short note on elements.