This happens early in embryonic development in females, where one of the two X-Chromosomes is randomly (and permanently) inactivated, as you said, in cells other than egg cells.
This phenomonon is actually called X-Inactivation.
X-Inactivation make sure that females, just like males, have a single functional copy of the X Chromosome in each and every one of their cells in their body.
Glad I could help, byee now
A. Computers were discovered in 1822
---- *Well, since there is really no specific ecosystem that was asked about in the question, I will just list some common and basic abiotic factors found throughout most ecosystems (maybe you can match this with the ecosystem you are talking about).
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Abiotic factors: nonliving parts of an ecosystem
Some abiotic factors include: ROCKS, SOIL, AIR, SUN, WATER, ETC.
Answer:
• An acid is an electrolyte that hydrolyses in water to release hydrogen ions.

• pH level of an acid;
- Strong acid → 0 - 3.8
- Weak Acid → 4.0 - 6.7