B3.1 Gas Exchange

What is the primary function of gas exchange in organisms?

• To facilitate digestion

• To regulate body temperature

• To obtain nutrients

• To obtain oxygen and remove carbon dioxide

How does the surface area-to-volume ratio change as organisms increase in size?

• It increases

• It decreases

• It remains constant

• It fluctuates

Which of the following adaptations helps larger organisms with gas exchange?

• Thick skin

• Increased metabolic rate

• Specialized respiratory systems

• Reduced body size

What property of gas exchange surfaces allows gases to pass through easily?

• Color

• Permeability

• Thickness

• Density

What role do dense networks of blood vessels play in gas exchange?

• They reduce oxygen levels

• They maintain concentration gradients

• They increase blood pressure

• They facilitate digestion

What is the function of surfactant in mammalian lungs?

• To transport carbon dioxide

• To absorb oxygen

• To reduce surface tension

• To increase surface tension

Which muscle contracts to increase the volume of the thoracic cavity during inhalation?

• Diaphragm

• Abdominal muscles

• Pectoral muscles

• Intercostal muscles

What is tidal volume?

• The maximum air exhaled after a full inhalation

• The volume of air remaining in the lungs after exhalation

• The volume of air inhaled or exhaled during a normal breath

• The additional air that can be inhaled with effort

What is the primary function of stomata in leaves?

• To regulate gas exchange

• To absorb water

• To provide structural support

• To store nutrients

Which factor(s) influence the rate of transpiration in plants?

• Wind

• Humidity

• Temperature

• Soil type