Edexcel AS Biology 4

Welcome to your Edexcel AS Biology 4

Tiny vessels that link arteries and veins.

Select the incorrect statement regarding COPD.

What is the first step of expiration?

What is the respiratory organ of an earthworm?

An advantage of gas exchange in water over the gas exchange in air.

Select the correct sentence regarding smoking.

The specific site of gas exchange in humans.

Which is not a function performed by the stomach?

A fluid secreted by the alveoli.

Number of openings in the right auricle.

The mammalian circulatory system is a ___________.

Select the incorrect statement regarding arteries.

When breathing, air is filtered, warmed and moistened in this organ.

Lungs are encased in thin membranes called ________.

What is the advantage of a thin wall in a respiratory surface?

Which of the following is not a function of surfactant?

Which of the following is not a component of gastric juice?

Which of the following aids in stretching and recoiling of alveolar walls?

Which of the following is not a characteristic of a double circulation?

Which of the following is not a reason for the evolvement of respiratory surfaces with high AV ratios?