In the respiratory system certain structures allow air to pass from the trachea to the lungs. They are lined with thin muscles and coated with epithelial cells. These structures are called
O bronchial tubes.
O alveoli.
O bronchioles.
O lobules.

Agene pool: a) is the collection of all the alleles found in a single species b) is the collection of all the alleles found in a single population c) is the collection of all the chromosomes found in a single population d) is the collection of genes in a species that allow the individuals to swim

Which of the following is a common response to cell signaling?

Which worm has eyespots that are used to detect light? a fluke b marine worm c planarian d tapeworm