H2O is a substance that that is classified as a compound. It is the chemical formula of water. A compound is two or more elements that have been chemically combined. In this question, water has two elements which are hydrogen (H) and oxygen (O). Two hydrogen atoms combine with one oxygen atom to form a compound. The answer will thus be B.
Lung volume varies from larger to smaller. People with smaller lung volumes have slightly smaller lung capacity with the partial pressure of oxygen being lower as well; while people with larger lung volumes have increased capacity of processing air. In terms of air movement, larger lung volume can contain and established more control of air getting inside and outside the lungs compared to smaller lung volume.
The answer is [ D ] According to me
Answer: The part of DNA that the teacher was modelling would be the backbone of DNA.
Explanation:
The DNA is made of double helical structure which is twisted. In the structure of DNA two strands are coiled among each other.
The DNA consists of the nitrogenous bases, phosphate groups and deoxy-ribose sugar.
The backbone of DNA is made up of sugar( alternating )and phosphate group.The nitrogenous bases such as adenine, cytosine ,guanine and thymine are joined to the deoxy-ribose sugar.
This backbone part was part that the teacher was making as a model by using two coiled springs.
