Answer:
DNA is the chemical name for the molecule that carries genetic instructions in all living things. The DNA molecule consists of two strands that wind around one another to form a shape known as a double helix.
Explanation:
A sound wave is a wave of compression and rarefaction, by which sound is propagated in an elastic medium such as air.
The correct option is D. There are four different nitrogenous bases in DNA molecules; these bases are joined together by different forces including hydrogen bonds. In DNA molecules, there are two hydrogen bonds between adenine and thymine while there are three hydrogen bonds between cytosine and guanine. Thus, the hydrogen bonds between cytosine and guanine is the stronger.
Answer:
BTB respond to the presence of carbondioxide by changing color.
Explanation:
Bromthymol blue is a chemical indicator dye that changes it color to yellow in the presence of an acid. It respond in the presence of carbondioxide and form carbonic acid, therefore lowering the pH. It becomes blue if the pH is greater than 7.6, it is green if the pH is between 6-7.6 and yellow if the pH is less than 6.
