What is the primary site of gas exchange in the respiratory system of mammals?

• Bronchi

• Trachea

• Alveoli

• Diaphragm

Which of the following best describes the function of alveoli in mammalian lungs?

• Transport oxygen to the body

• Warm and humidify the air

• Increase the surface area for gas exchange

• Produce mucus to trap particles

How does the countercurrent exchange system in fish gills enhance gas exchange?

• By allowing water and blood to flow in the same direction

• By allowing water and blood to flow in opposite directions

• By decreasing the surface area for gas exchange

• By increasing the temperature of the water

What is the main advantage of having a countercurrent exchange system in fish gills?

• It conserves body heat

• It maximises oxygen uptake

• It allows fish to breathe air

• It reduces the amount of water needed for gas exchange

Which of the following structures in fish are primarily responsible for gas exchange?

• Scales

• Fins

• Gills

• Swim bladder

During ventilation in fish, what is the sequence of water flow?

• Mouth → Gills → Operculum

• Operculum → Gills → Mouth

• Gills → Mouth → Operculum

• Mouth → Operculum → Gills

What is the role of the diaphragm in the respiratory system of mammals?

• It filters the air entering the lungs

• It aids in the exchange of gases in the alveoli

• It helps to inflate and deflate the lungs

• It transports oxygen to the bloodstream

Which of the following adaptations in fish gills increases the efficiency of gas exchange?

• The presence of a single large gill filament

• The reduction of blood flow to the gills

• The thinness of the gill lamellae

• The thickening of the gill arches

In fish, what is the purpose of the operculum?

• To aid in the digestion of food

• To protect the gills from debris and predators

• To pump water over the gills

• To extract oxygen from water before it reaches the gills

What is the function of gill rakers in fish?

• To aid in the digestion of food

• To filter out debris and unwanted particles from the water

• To extract oxygen from water before it reaches the gills

• To pump water over the gills