Respiratory System 6, Alveoli and respiratory membranes

Alveoli and the respiratory membranes, MCQs

Which of the following is not part of the conducting system of the respiratory system?
a. Alveoli.
b. Terminal Bronchioles
c. Nose
d. Pharynx

Cells lining the alveoli are;
a. thrombocytes
b. lymphocytes
c. pneumocytes.
d. hepatocytes

Gaseous exchange occurs in the
a. Trachea
b. Terminal bronchioles
d. Alveoli.
e. Bronchi

Which of the following correctly describes the passage of oxygen from the
alveoli into the blood?
a. Oxygen is transported across the respiratory membranes by active transport
mechanisms.
b. Oxygen diffuses up a diffusional gradient to enter the blood.
c. Oxygen diffuses from areas of low concentrations in the alveoli to areas of higher
concentration in the blood.
d. Oxygen diffuses from areas of high concentrations in the alveoli to areas of lower
concentration in the blood.

Surfactant is produced by
a. Red blood cells
b. Ciliated endothelial cells
c. Type I alveolar cells
d. Type II alveolar cells.

Atelectasis is reduced in the smaller airways as a result of;
a. increased pressure in the pulmonary veins
b. increased pressure in the pulmonary artery during right ventricular systole
c. surfactant increasing surface tension
d. surfactant decreasing surface tension.

[thebooboobus]

Thank you for your videos! I started to think I wasn't smart enough to venture into a carer in medicine. I was close to leaving uni but your videos have helped me out alot! It has all started to come together.

[Rene-uzeb]

10:43 note that most (75-80%) of the recoil actually comes from the remaining surface tension, not the membrane.

Great info, surprised to learn about all the negative effects of smoke on the lungs, given that we evolved around smoke/cooking. Not only damaging alveoli via the exploding macrophages: smoke reduces surfectant production, and also reduces the actual effectiveness of the remaining surfectant.

Acute influence of cigarette smoke on secretion of pulmonary surfactant in rat alveolar type II cells in culture, 1996

The effect of smoke inhalation on pulmonary surfactant. 1980

Otoh, more recent research seems to be more ambivalent about the surfectant degrading quality of smoke. In particular, sulphur dioxide released from wood or tobacco burning is known to reduce water surface tension. So it probably has a similar effect on the lungs, at least that part of the smoke. Which would explain part of the addictiveness: on the one hand smoking reduces surfectant production, making it harder to breathe because of excessive force against inhalation, but then a hit of SO2 from a smoke would reduce that tension again. Makes sense to me from my dabbling in smoking, just guessing though.

[amank]

You’re such a great teacher, your knowledge is treasure thanks gor sharing it❤️

[sambhatol]

Very very nice teaching techniques....not everybody is good at....
There are lots of medicos who are related to teaching but not all are good at even explaining simple things....
Very much apreciating...

[leasantos]

So much amaze on how you simplify the explanation. You are gifted. Thank you Dr. God bless you

[MediSparkEdu]

Simply amazing... a knack for making things understandable and a joy to learn.

[sebastianberrittella]

What an amazing explanation!! thank you so much Dr!!

[shashimoghe]

Thanks dr john Campbell sir for explaining this difficult topic in such easy manner good wishes 17/05/2021

[patina]

Thank you for the video! Is fantastic!

[noemihernandez]

Thank you DR! The videos are amazing and so helpful !

[meshackifeanyi]

Ur lectures are wonderful sir thank u so much

[brownsil]

Thanks very much Dr, your teachings are clearly understandable. I will be glad if you can lecture us on stroke and renal colic. 🙏

[mokie]

This great explanation makes me love the amazing human body even more

[dr.yuvarajanpalanisamy]

THANK YOU SIR . nice microscopic explanation . i have still doubt how the rbc carries O2 and transfers, likewise Co2 which .between the respiratory membrane how the exchange occurs .and you said by diffusion gradient o 2 and co 2 is transferred.but not clear to me .for example the atmospheric o2 is higher than o2 in water why diffusion is not occurring.and in Pneumocytes its occurs easily

[CM-uoqs]

Dr John, love your content! Can you please explain how an airborne virus (such as coronavirus) can pass into the blood stream through the alveoli?

[Zainabz]

This is very helpful, i can't thank you enough 💚💚

[rashkamohamed]

Thank u very much i learn alot from you thank u again

[heidireeble]

One gets almost dizzy thinking of all the body 'does' on a daily basis and what a super machine it really is...

[javillerena]

Thanks again Dr Campbell! ...I have a question
O2 and CO2 exist is a relatively small percentage. Why don't we have a gaseous exchange with other elements, such as Nitrogen?....which is about 78% of the air we breathe. Is there any kind of filter inside the alveoli?

[clavo]

RE: Respiratory membrane physical expansion as relief for CoVid-19: As a former asthma sufferer; I had an experience with smoking pot that surprised me, because generally smoke and asthma don't mix well. The vascular diluting effect of something in pot (the reason your eyes get bloodshot) actually helped me breath better (I think) during an asthma attack. I was about 18 at the time, some 45 years ago! Maybe someone can extrapolate a relief for CoVid-19 lung debilitation effect from this information. e.g. can oxygenation be improved via dilation of the lungs alveoli; or, can the vascular dilution effect of some chemical in pot smoke affect the respiratory membrane so as to improve the gas exchange when CoVid-19 has attacked the lungs?