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Wikipedia:Reference desk/Archives/Science/2021 October 16

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October 16

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Are eggs created in the body of birds by stem cells?

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What is the main type of cell in birds which makes the "genesis" of eggs?

Thanks, 49.230.20.227 (talk) 00:36, 16 October 2021 (UTC)[reply]

In birds, as in mammals, oogenesis proceeds from oocytes, specialized cells in the ovaries. The unfertilized egg (or fertilized but before embryogenesis has begun) itself is one cell.  --Lambiam 08:53, 16 October 2021 (UTC)[reply]

SI unit in Electro chemistry

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If EMF and Voltage are not same, but why using same SI unit for both?

Volt is the SI unit of both the EMF and the voltage. Rizosome (talk) 05:58, 16 October 2021 (UTC)[reply]

Voltage is the unit for Electromotive force. ←Baseball Bugs What's up, Doc? carrots07:04, 16 October 2021 (UTC)[reply]
In both cases the quantity can be defined as the amount of work on a test charge moving in an electric field, so they have the same dimension (specifically, M L2 T −3 I −1 ). As you can read in our article Electromotive force, it can be measured in two-terminal devices as the voltage between the terminals, so naturally the same unit is used.  --Lambiam 07:37, 16 October 2021 (UTC)[reply]

Anti-Stokes %.

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What are some examples of things that have a highest % of anti-Stokes? Like most emissions is like 95% Stokes, 5% anti-Stokes. What phenomenon have some of the highest percentage of anti-Stokes? 67.165.185.178 (talk) 12:16, 16 October 2021 (UTC).[reply]

Are you talking about Stokes shift? ←Baseball Bugs What's up, Doc? carrots13:05, 16 October 2021 (UTC)[reply]

Plant identification

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Hi, I have described these as "cycads". Can anyone just check and confirm this, or even provide a species or more specific type name? ITookSomePhotos (talk) 16:27, 16 October 2021 (UTC)[reply]

Aren’t these just small palm trees? Here they are described specifically as date palm trees.  --Lambiam 21:29, 16 October 2021 (UTC)[reply]
(edit conflict) I think jubaea chilensis or Chilean wine palm is a likely candidate. This article has a picture of a similar one growing happily on a traffic roundabout in London. Ventnor Botanic Gardens on the Isle of Wight has avenues of the things, according to this article, whose collection of Arecaceae have been given National Plant Collection status and says that warmer weather since the 1970s has made the island a good home for palms, most types of which normally struggle with the British weather. The most common palm seen here in southern England is the hardy Cordyline australis or cabbage palm from New Zealand, but these ain't they. Alansplodge (talk) 21:39, 16 October 2021 (UTC)[reply]

Silly me. I'll rename it. ITookSomePhotos (talk) 07:50, 17 October 2021 (UTC)[reply]