During a gas exchange investigation, measurements were recorded from four animals that were observed as they breathed normally over a period of 5 minutes. Note that the efficiency of gas exchange was the same in all four animals and that tidal volume refers to the volume of air that moves into the lungs with each normal breath.
Which animal had the highest oxygen intake during five minutes of normal breathing?
Four patients, all male and in the age range 60-65, visited their family doctor complaining of breathing difficulties. The doctor asked each man a series of questions about his symptoms and lifestyle.
Based upon the men's lifestyles and their lists of symptoms, which patient is at the highest risk of lung cancer?
Patient
Smoker / how many cigarettes?
Coughing?
Fatigue?
Appetite?
Other
A.
Yes - 20 per day since age 18
Yes - sometimes with blood
Every day
Poor
Worked with asbestos in his 20s
B.
Yes - 5 per day since age 18
Yes - frequent
No
High
BMI = 39
C.
No
Yes - especially at night
Occasionally
Normal
Dry, flaky skin
D.
40 years at 20 per day but quit smoking completely 5 years ago
Anti-smoking groups have conducted a long-running campaign to link smoking to lung cancer in a causal relationship. This relationship was finally proved in the British Doctors Study that ran from 1951-2001.
Which is not a factor that contributed to this causal link being proven?
High response rates from patients were seen in the study.
Epidemiological data was gathered over a long period of time.
Many confounding variables were taken into account and then eliminated.
Many experiments were carried out to increase the experimental data available.
Increased nerve impulse transmission occurs in parts of the brain.
Heart rate increases.
The risk of changes to genes involved in controlling the cell cycle increases.
Which row of the table contains the smoking-related causes of effects 1-4? Note that 'tar' in this context is a term used for the combination of insoluble and viscous chemicals found in tobacco smoke.
1.
2.
3.
4.
A.
Increased activity of phagocytes
Increased activity of phagocytes
Nicotine in tobacco binds to acetylcholine receptors
Stimulation of the glands that secrete epinephrine/adrenaline
B.
Stimulation of the glands that secrete epinephrine/adrenaline
Inhalation of tar
Stimulation of the glands that secrete epinephrine/adrenaline
Increased activity of phagocytes
C.
Increased activity of phagocytes
Nicotine in tobacco binds to acetylcholine receptors
Stimulation of the glands that secrete epinephrine/adrenaline
Inhalation of tar
D.
Inhalation of tar
Inhalation of tar
Nicotine in tobacco binds to acetylcholine receptors
Stimulation of the glands that secrete epinephrine/adrenaline