shagieIsMe
shagieIsMe t1_iy0i7n6 wrote
Reply to comment by mike_pants in Cats are in stock by vladgrinch
/r/bodegacats
shagieIsMe t1_iuj9xgy wrote
Reply to comment by Enocli in How do white blood cells know in which direction there is a bacteria? by Enocli
The classic "The Inner Life of a Cell" ( https://vimeo.com/90405549 and narrated - https://youtu.be/QplXd76lAYQ ) is about that process that changes a WBC from "rolling along" to stoping and then changing form and all the molecular mechanisms that activate to do this.
Kurzgesagt also has a video on the immune system and bacterial infection. https://youtu.be/lXfEK8G8CUI
shagieIsMe t1_jbhx2su wrote
Reply to comment by Vitztlampaehecatl in Is there a fertile creature with an odd number of chromosomes? by TheBloxyBloxGuy
Not soon... but eventually.
https://www.sciencealert.com/the-y-chromosome-is-slowly-vanishing-a-new-sex-gene-could-be-the-future-of-men
> The sex of human and other mammal babies is decided by a male-determining gene on the Y chromosome. But the human Y chromosome is degenerating and may disappear in a few million years, leading to our extinction unless we evolve a new sex gene.
> The good news is two branches of rodents have already lost their Y chromosome and have lived to tell the tale.
> A new paper in Proceedings of the National Academy of Science shows how the spiny rat has evolved a new male-determining gene.
(the paper is Turnover of mammal sex chromosomes in the Sry-deficient Amami spiny rat is due to male-specific upregulation of Sox9 - https://www.pnas.org/doi/10.1073/pnas.2211574119 )
Chasing links and searches:
NYT A Gene Mystery: How Are Rats With No Y Chromosome Born Male?
> ...
> Both female and male Amami spiny rats have only one X chromosome, an arrangement only known to occur in a handful of rodents among mammals. Arata Honda, associate professor at the University of Miyazaki and the lead author of the paper, said in an email that he was partly motivated to study Amami spiny rats in the hope that learning about them might reduce their risk of extinction.
> No one knows how or why, but at some point the rats lost their Y chromosome and, along with it, an important gene called SRY that’s considered the “master switch” of male anatomical development in most mammals.
And this also lead's to the OP's question: https://en.wikipedia.org/wiki/Ryukyu_spiny_rat
> The Ryukyu spiny rat (Tokudaia osimensis) is a species of rodent in the family Muridae. Endemic to Amami Ōshima island in the Amami Islands of the Ryukyu archipelago of Japan, its natural habitat is subtropical moist broadleaf forest. The karyotype has an odd diploid number, 2n = 25. Like its relative T. tokunoshimensis, it has lost its Y chromosome and SRY gene.
http://www.departments.bucknell.edu/biology/resources/msw3/browse.asp?id=13001850
> The unique chromosomal complement of this species (2n = 25, with no X in the female or visible Y in the male) first documented by Honda et al. (1977) and corroborated by Kimiyuki et al. (1989)