screen317 t1_je93z3b wrote on March 30, 2023 at 9:16 AM

Reply to comment by PandeiroMan in Why are there multiple species of various life forms, but humans only have one? Are there other complex single-species organisms? by CyberOGa3

What evidence

screen317 t1_je93pgl wrote on March 30, 2023 at 9:12 AM

Reply to comment by bigfatfurrytexan in How did eye lense evolve? by TheSonOfKayra

> and evolution was rather rapid fire by comparison to today

Important to note that we are in the middle of a mass extinction period.

screen317 t1_jbsngi7 wrote on March 11, 2023 at 11:57 AM

Reply to comment by Jale89 in I just learned that the known shortest DNA in an “organism” is about 1700 base pairs in a certain virus. Is there a minimum amount of “code” required for an organism (or virus) to function in any capacity? by mcbergstedt

> OP, the virus mentioned doesn't really represent an organism because it requires the mechanisms of a cell to replicate

There are a slew of obligate parasitic eukarotes that this definition disqualifies as an organism.

screen317 t1_jb924xl wrote on March 7, 2023 at 10:02 AM

Reply to comment by Supraspinator in Where are birds Hematopoietic stem cells? by Mikedc1

The real bursa equivalent is the spleen, where transitional B cell development occurs after central tolerance.

screen317 t1_j9epak8 wrote on February 21, 2023 at 11:20 AM

Reply to comment by GreenHandbag2 in How and why does asphyxiation induce euphoria? by Ausoge

Evolution works at the population level to ensure genes get passed down to the next generation. The deadly genetic causes of asphyxiations as children have already been selected out.

As a general note, evolution has no goals and doesn't guarantee "better" over time.

screen317 t1_j9e0puw wrote on February 21, 2023 at 5:54 AM

Reply to Why does a stem cell recipient not inherit the immune system of the donor? by Kevin4938

Immune memory is not stored in bone marrow stem and progenitor cells. These are the only cells that expand to reconstitute the recipient's immune system.

You don't transplant memory cells that live in secondary lymphoid organs like the spleen and lymph nodes.

screen317 t1_j5j4x7n wrote on January 23, 2023 at 11:02 AM

Reply to comment by Perfect-Height-8837 in How do we know how old viruses are? by Darth_Fatass

There are tons of cellular obligate parasites that render the discussion moot

screen317 t1_j0e4rhx wrote on December 15, 2022 at 11:52 PM

Reply to comment by shadowyams in Will my kids inherit the genetic mutations that I aquire during my lifetime? by RedditScoutBoy

Bone marrow cells can however travel all the way across the body to other bones though, pretty cool!

screen317 t1_ir8ri2z wrote on October 6, 2022 at 4:25 AM

Reply to comment by longshot_MD in Can t-cells turn into cancer? Are they any more or less likely to do so than any other cell? by iBluefoot

> Abnormal T-cell malignancies, therefore, most commonly present as a hematologic malignancy which is to say the problem is in one of the early stage cells in the bone marrow

This is not accurate. ETPs (T cell precursors) don't have their Rag genes active and wont be susceptible to T-ALL. So, there aren't really any BM-derived T cell malignancies. It's primarily Pre-T ALL that originates in the thymus, since those are the cells actively rearranging DNA.