Gas exchange in humans

9.Which of the following is NOT a feature that helps alveoli maximise diffusion?

10.A student observes a diagram of an alveolus and its surrounding capillary. Which of the following correctly describes the direction of diffusion for oxygen and carbon dioxide?

11.The diagram shows an alveolus and a surrounding capillary. Which labelled part is the site where oxygen and carbon dioxide are exchanged?

12.The diagram shows a cross-section of an alveolus. Which structure is labelled X?

13.The diagram shows a cross-section of an alveolus and a surrounding capillary. Which labelled part is the site where oxygen and carbon dioxide are exchanged?

14.The diagram shows the internal structure of a leaf. Which labelled part is the site of gas exchange?

15.A student measures the oxygen concentration in the air entering the alveoli and in the blood leaving the alveoli. Which of the following best describes the expected result?

16.The table shows the percentage of gases in inhaled and exhaled air. Which row is correct?

17.A patient has a lung disease that reduces the surface area of the alveoli. Which of the following would be a direct consequence?

18.During exercise, the breathing rate increases. Which of the following explains why this is necessary?

19.A scientist measures the rate of diffusion of oxygen across an alveolus. Which of the following changes would increase the rate of diffusion?

20.Which of the following correctly describes the direction of diffusion of carbon dioxide at the alveoli?

21.In an experiment, a model lung is made using a balloon inside a jar. When the rubber sheet at the bottom is pulled down, the balloon inflates. Which part of the real respiratory system does the rubber sheet represent?

22.A person breathes in and out. Which of the following shows the correct order of structures that air passes through during inhalation?

23.In an experiment to model gas exchange, a student sets up a jar with a balloon inside to represent a lung. The balloon is attached to a glass tube that goes through the lid. The bottom of the jar is covered with a rubber sheet. When the student pulls the rubber sheet downward, the balloon inflates. Which part of the model represents the diaphragm?

24.A student investigates the effect of exercise on breathing rate. She counts the number of breaths per minute at rest, then after 1 minute of running on the spot, and again after 2 minutes of rest. Which of the following is the most likely explanation for the change in breathing rate after exercise?

25.A student sets up an experiment using a beaker of water and a glass tube to model diffusion. She places a drop of red food coloring at the bottom of the beaker and observes that the color spreads throughout the water over time. Which of the following changes would increase the rate of diffusion of the food coloring?

26.Which of the following is the correct order of structures that air passes through during exhalation?

27.A scientist uses a spirometer to measure the volume of air a person inhales and exhales. The person breathes normally for 2 minutes, then breathes as deeply as possible. Which of the following can be calculated from these measurements?

28.A student builds a model of the respiratory system using a plastic bottle, a balloon, and a rubber sheet. Which part of the model corresponds to the alveoli?

29.A student investigates the effect of surface area on the rate of diffusion. She uses two cubes of agar jelly containing a pH indicator: one cube with side length 1 cm and another with side length 2 cm. She places both cubes in a beaker of acid and times how long it takes for the indicator to change color completely. Which cube will change color first, and why?

30.Which of the following statements about diffusion is correct?

31.A student uses a respirometer to measure the rate of oxygen consumption in germinating seeds. The apparatus includes a sealed container with the seeds, a manometer, and a chemical that absorbs carbon dioxide. Which of the following best explains why the carbon dioxide absorbent is necessary?

32.In an experiment, a model lung is made using a balloon inside a jar. When the rubber sheet at the bottom is pulled down, the balloon inflates. Which part of the model represents the diaphragm?

33.A student investigates the effect of surface area on the rate of diffusion. She uses two cubes of agar jelly containing a pH indicator: one cube with side length 1 cm and one with side length 2 cm. She places each in a beaker of acid and measures the time for the colour to change. Which cube will change colour faster and why?

34.A student uses a respirometer to measure the rate of oxygen consumption in germinating seeds. The apparatus includes a sealed container with the seeds, a manometer, and a substance to absorb carbon dioxide. Which of the following would cause the coloured liquid in the manometer to move towards the seeds?

35.A student sets up a model lung using a plastic bottle, a Y-shaped tube, two balloons (one inside the bottle to represent a lung, one attached to the bottom to represent the diaphragm), and a rubber sheet. When the rubber sheet is pulled down, the balloon inside inflates. Which part of the model corresponds to the alveoli?

36.A student uses a respirometer to measure the rate of oxygen consumption in germinating seeds. The apparatus includes a sealed container with the seeds, a manometer, and a syringe. Which of the following would cause the coloured liquid in the manometer to move towards the seeds?

37.In an experiment to investigate the effect of surface area on the rate of diffusion, a student prepares two agar cubes of different sizes, each containing a pH indicator that changes colour when carbon dioxide diffuses in. The cubes are placed in a solution of carbon dioxide. Which of the following would be the most appropriate way to measure the rate of diffusion?

38.A scientist uses a spirometer to measure lung volumes. The trace shows tidal volume and vital capacity. Which of the following best defines vital capacity?

39.A student investigates the effect of exercise on breathing rate and depth. She records the number of breaths per minute and the volume of each breath at rest and after exercise. Which of the following combinations of changes would most likely be observed after exercise?

40.Which of the following is a waste product of respiration that is removed from the body through the lungs?

41.Carbon dioxide is a waste product of respiration.

42.Diffusion is the movement of particles from a low concentration to a higher concentration.

43.Alveoli give the lungs a small surface area.

44.There are small blood vessels called capillaries wrapped around each alveolus.

45.Blood capillaries have thick walls to protect them.

46.Gas exchange is necessary for providing oxygen to the body's cells.

47.What is the name of the tiny air sacs in the lungs where gas exchange takes place?

48.Match each structure to its correct description.

49.Arrange the following structures in the correct order for the passage of air from the mouth to the alveoli during inhalation.

50.Which of the following are adaptations of alveoli that maximise the rate of gas exchange? (Select all that apply)

51.Describe three ways the alveoli maximise diffusion in the lungs.

52.When you exhale, describe the route that carbon dioxide takes to be expelled from the body.

53.Compare the concentration of oxygen and carbon dioxide in the blood before and after it passes through the alveoli.

54.Complete the sentences about gas exchange.

55.The rate of diffusion of oxygen across an alveolus is 0.5 mg/min. If the surface area of the alveoli is doubled, what will be the new rate of diffusion in mg/min? (Assume all other factors remain constant)

56.The rate of diffusion of oxygen across an alveolus is 0.5 mg/min. If the surface area of the alveoli is doubled, what will be the new rate of diffusion in mg/min? (Assume all other factors remain constant)