Blood Composition and Clotting

What is the approximate percentage of oxygen in the air that animals breathe?

21%

What is the driving force for the diffusion of a gas?

The partial pressure of the gas

As altitude increases, what happens to the atmospheric pressure?

It decreases

What is the partial pressure of oxygen in air at sea level?

160 mmHg Signup and view all the answers

Which of the following factors does not influence the solubility of a gas in water?

Color of the water Signup and view all the answers

What is the sum of the pressures exerted by each gas in the mixture of air?

Atmospheric pressure Signup and view all the answers

What is the approximate percentage of plasma in the total volume of blood?

50% Signup and view all the answers

Which type of blood cell is responsible for transporting oxygen in the body?

Erythrocytes Signup and view all the answers

What is the function of platelets in the blood clotting process?

To form a platelet plug and facilitate the formation of a fibrin-based clot Signup and view all the answers

What is unique about the erythrocytes of mammals compared to those of other vertebrates?

They lose their nuclei upon maturation Signup and view all the answers

What is the function of leukocytes in the body?

To protect and defend the body against infection Signup and view all the answers

Which of the following components of blood is responsible for carrying nutrients, ions, and waste products?

Plasma Signup and view all the answers

What is the mathematical relationship between blood pressure, blood flow, and resistance?

Blood flow is directly proportional to the difference in pressure and inversely proportional to the resistance Signup and view all the answers

What is the effect of increasing the radius of arterioles on blood flow?

It increases blood flow by decreasing resistance Signup and view all the answers

What is the net effect of vasodilation on blood pressure?

It decreases blood pressure by decreasing resistance Signup and view all the answers

What is the relationship between cardiac output and blood pressure?

Cardiac output is directly proportional to blood pressure Signup and view all the answers

What are the two parameters that determine cardiac output?

Heart rate and stroke volume Signup and view all the answers

What is the effect of increased total peripheral resistance on blood pressure?

It increases blood pressure by increasing resistance to blood flow Signup and view all the answers

What is the primary function of ventilation in animals?

To bring oxygenated water or air into contact with the gas-exchange organ Signup and view all the answers

Which type of gas-exchange organ is characterized by a large surface area and thin, delicate structure?

Body surface Signup and view all the answers

What is the benefit of countercurrent exchange in gill ventilation?

To maximize oxygen diffusion into the blood Signup and view all the answers

Which type of animal has external gills?

Invertebrates Signup and view all the answers

What is the role of the circulatory system in tracheal systems?

To play no role in gas exchange Signup and view all the answers

What is the relationship between pressure and volume according to Boyle's law?

Inversely proportional Signup and view all the answers

How do air-breathing vertebrates ventilate their lungs?

By negative pressure filling Signup and view all the answers

What is the function of spiracles in insects?

To facilitate gas exchange Signup and view all the answers

Which type of gas-exchange organ is found in amphibians?

Body surface Signup and view all the answers

What is the purpose of the lamellae in gill filaments?

To facilitate gas exchange Signup and view all the answers

What is the function of the upper respiratory structures in the mammalian respiratory system?

To warm, humidify, and filter the air Signup and view all the answers

What is the purpose of the pleural sac in the mammalian respiratory system?

To protect the lung tissue and facilitate movement of the lungs Signup and view all the answers

During inhalation, what happens to the volume and pressure of the lungs?

Volume increases, pressure decreases Signup and view all the answers

What is the primary function of surfactant in the mammalian respiratory system?

To decrease surface tension in the alveolar walls Signup and view all the answers

What is the average tidal volume for humans at rest?

0.5 L (500 mL) Signup and view all the answers

What is the difference between tidal ventilation and the unidirectional flow-through system of fishes?

Tidal ventilation is less efficient than the unidirectional flow-through system Signup and view all the answers

What is the purpose of the bronchioles in the mammalian respiratory system?

To regulate air flow through smooth muscle contraction Signup and view all the answers

What is the site of gas exchange in the mammalian respiratory system?

Alveoli Signup and view all the answers

What type of cells form the thin alveolar walls in the mammalian respiratory system?

Type I cells Signup and view all the answers

What is the direction of air flow during exhalation in tidal ventilation?

The same route as inhalation Signup and view all the answers