1.1. Complete the following sentence.

Choose the answer from the box.

The thorax is separated from the abdomen by the __________________

1.2. Which structure connects a bronchus to an alveolus?

1.3. Figure 1 shows the human lungs and associated structures.

Name airways X and Y.

Figure 1 

1.4. Figure 2 shows a number of features and functions relating to the alveolus.

Figure 2

Draw one line from each feature to the correct function.