Maybe the decrease in plants they eat
Otherwise known as deforestation
The inside surface area is shaped in a crescent. It consists of a spiral valve which is made up of the small intestine. Although the dogfish shark has a relatively short small intestine compared to other animals, therefore, the spiral valve allows for a more compact form of the small intestine.
Hence, this structure provides maximum surface area over a relatively short distance in order to make the absorption of nutrients efficient achieved from the food, the sharks had from eating different sea animals.
Answer:
From smallest to largest:
Capillaries, alveoli, bronchi. bronchioles, trachea, pharynx, nasal cavity.
Some signs of a chemical change are a change in color and the formation of bubbles. The five conditions of chemical change: color chage, formation of a precipitate, formation of a gas, odor change, temperature change.