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Question of the Week / QotW - 21.06.14 - Why is a crocodile's skin so bumpy?

« on: 14/06/2021 10:27:47 »

Our latest question comes from one of our younger listeners, five-year-old Johan...

Why is a crocodile's skin bumpy and not smooth?

Can anyone chip in?

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Question of the Week / QotW - 21.05.17 - Why doesn't overcooking unhealthy food make it healthy?

« on: 17/05/2021 18:05:19 »

For this week's question, listener Kelvin asks:

We are told not to overcook our vegetables because this kills the nutrients. Now if that's the case, why don't we just overcook the food we enjoy and not run the risk of putting on weight?

Any thoughts?

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Question of the Week / QotW - 21.04.26 - What do flies do in winter?

« on: 26/04/2021 09:22:38 »

Listener Jeffrey wants to know:

We’ve had a cold and snowy winter, and I’ve had to shovel my driveway every few days. We had a fly in our house, and I was curious if it survived the cold somehow, or recently hatched?

What happens to flies during winter?

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Question of the Week / QotW - 21.04.19 - How do zip files work?

« on: 19/04/2021 12:05:08 »

This week's question comes from listener Ellie:

How do zip files work on my computer?

Can anyone unzip this one?

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Question of the Week / QotW - 21.03.22 - How have species evolved to get different chromosome numbers?

« on: 22/03/2021 13:54:12 »

This week's question comes from listener Mattie:

If humans have too many or too few chromosomes it can cause them to be infertile. So how did different creatures get different numbers of them? For example, humans have 46 chromosomes, but mice have 40.

Can anyone assist?

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Physiology & Medicine / Why do we get bruises?

« on: 10/02/2021 16:56:00 »

Abigail asks:

Why do we get bruises? Why is it that some areas of my body are more prone to getting bruised than other areas?

Furthermore, why is it that some people bruise more easily than others?

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Cells, Microbes & Viruses / How do DNA and RNA chains evolve?

« on: 09/02/2021 18:46:46 »

We received the following from listener Andrew:

I have been thinking about the origins of life in the context of random processes at the molecular biology level. The main problem seems to be the building of RNA or DNA chains of considerable length. The coronavirus has 30k bases.

With 2 to the power 2 possible bases, the coronavirus has 2 to the power 60k possible configurations - which is about ten to the power 18k. It would be expecting a lot from random processes if this level of complexity were to be achieved in one trial rather than being built up gradually by the assembly of components which were themselves built by random processes.

How might a random process build an RNA or DNA chain?

It seems to me that enzymes would play a significant role in this. Specifically there would need to be an enzyme whose purpose would be to add a base to an existing chain, thus extending it by one base unit. The choice of base unit would either be random or be determined by the enzyme itself if there was one particular base per enzyme, with four distinct enzymes.

So my question is, do these enzymes actually exist?

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COVID-19 / Should world vaccine distribution prioritise countries with dangerous variants?

« on: 02/02/2021 15:28:21 »

Listener Mark raises the question:

The WHO stated over the last few days that the COVID vaccines should be rolled out equitably. But surely this is not scientifically valid for the world - surely the way to distribute it at a world level is first to distribute it to countries where a worrisome variant appears in large numbers, i.e. the UK, Brazil, South Africa? This will benefit the whole world by stopping more infectious variants spreading to the rest of the world, and also preventing these particular variants mutating much further away from the original.

Obviously the whole population including all children should be vaccinated as far as possible in these countries before spare vaccines are given to other countries. This will be the most effective distribution of vaccines as far on a global level surely. Then to countries that are being hardest hit with the highest number of deaths per 100,000.

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Question of the Week / QotW - 21.02.01 - When are we going to run out of music?

« on: 01/02/2021 14:22:02 »

This week's question comes from listener Dennis:

Assuming there are a finite number of musical notes - chords, notes, octaves - at what point, how many years, would we use all combinations of musical themes such that no more music could be created?

Any back-of-the-envelope calculations?

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Physics, Astronomy & Cosmology / The universe is 13.8b years old, yet we've seen a galaxy 13.4b light years away?

« on: 01/02/2021 14:18:44 »

Tony asks:

The current estimate of the age of the universe is about 13.8 billion years, yet the furthest object known is 13.4 billion light years away from us. That only leaves 0.4 billion years difference. How is this explained?

Also if nothing can exceed the speed of light, surely that implies that the universe is expanding at the speed of light? Or is there an idea that its speed slows the further it travels, which would give us different values of distance based on red shift?

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Physiology & Medicine / Could electrical interference disrupt your body without making contact?

« on: 28/01/2021 16:27:34 »

Brian asks:

An electromagnetic pulse can disable electrical devices. Without making physical contact (like a taser or lightning), are there similar ways the electrical system in a person can be disrupted by some form of external interference? For example, could some type of device scramble electrical activity in a person’s brain or nervous system?

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COVID-19 / At what temperature are hospital linens & towels washed?

« on: 27/01/2021 16:46:53 »

Here's a question from listener Joan:

At what temperature are hospital linens & towels washed?

Some years ago, as I recall, there was advice given that it was unnecessary for hospitals & the general public to wash all linens & towels at 60 degrees minimum. The suggestion was for 30 or 40 degrees which I understand was taken on board - it would save money & the planet(?)

My concern, in this present circumstance with COVID-19, is that hospitals especially may still be washing at the lower temperatures, which in my opinion does not kill all bacteria etc. I am not a medical or scientific person but I have observed the increase in sepsis & now "go into hospital for something else & catch COVID".

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COVID-19 / My daughter thinks the vaccine is poison. How can I convince her otherwise?

« on: 26/01/2021 17:58:27 »

Viv asks:

I have a 48 year old daughter with two children. She is absolute adamant that when her turn comes, she will not have the vaccine. She will not “inject her body with poison”. We have both had ours with no reaction at all and feel very grateful and look forward to our second one.

What do you suggest I say to my daughter to persuade her to have it? It really worries me from both her own point of view and the children’s.

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COVID-19 / Is a methatrexate injection for arthritis a problem for the COVID vaccine?

« on: 25/01/2021 17:03:11 »

Carol asks:

I have a 17.5mg methatrexate injection weekly for rheumatoid arthritis. I cannot find any advice on whether I should leave it off before my COVID vaccine or to continue, and also if it's okay to have it at all?

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COVID-19 / Will our future generations build an immunity to the coronavirus?

« on: 20/01/2021 18:09:16 »

Jonathan asks:

Will our future generations build an immunity to the coronavirus, or will it be subject to particular mutations like the flu virus?

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COVID-19 / Would prior anaphylactic reactions make it unsafe to get the vaccine?

« on: 19/01/2021 17:31:43 »

Darren asks:

I have had two anaphylactic reactions: one to tuna fish 25 years ago, and another with a wasp sting 12 years ago, hence I carry a couple of EpiPens around with me. Could I still get the COVID vaccine?

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Physics, Astronomy & Cosmology / Why do glass windows & mirrors squeak when you clean them?

« on: 15/01/2021 17:21:56 »

Margaret asks:

Why do glass windows & mirrors squeak when you clean them?

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COVID-19 / I am 78 and care full time for my wife. Am I in the UK vaccine priority group?

« on: 14/01/2021 17:42:07 »

Listener Colin sent us the following:

My wife needs end-of-life care. I have a care agency that visits five times a day, but I’m her main carer as her husband. I am 78, my wife is 79, and if I was taken ill with coronavirus my wife would end up in care.

I note on the government website that I should be in the priority group for the first vaccination. Could you tell me if this is correct?

Can anyone interpret the guidelines better than me, especially how they're defining "health and social care workers at high risk"? https://www.nhs.uk/conditions/coronavirus-covid-19/coronavirus-vaccination/coronavirus-vaccine/

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Physics, Astronomy & Cosmology / As I fill my bird bath, why does the hose nozzle get sucked towards the bottom?

« on: 13/01/2021 17:40:09 »

George sent us the following observation from the bird bath on his balcony:

As I fill up the bird bath with the garden hose and I push the hose nozzle closer to the bottom (to prevent spray), I notice that the hose suddenly gets drawn downwards when almost at the bottom.

My only thought was that the liquid "forces" created a negative pressure to "pull" the nozzle to the bottom... much like the differing air pressures on an aircraft wing.

Can anyone explain this phenomenon?

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COVID-19 / Would an extended dosage interval work for the Oxford vaccine?

« on: 12/01/2021 18:19:50 »

John asks:

I am 70 and expecting to get COVID-19 vaccine, probably the Oxford/AstraZeneca one. However, the government is extending the dosage interval for the Pfizer vaccine. I understand their reasoning, but I am concerned that this can't be extrapolated to the Oxford vaccine, as a dosage error improved its efficacy significantly. Do you know if it's being proposed?