The aliens in this episode insist on making their own android bodies, because any the Federation could supply would be comparatively crude. They are then seen building android bodies using bulky electronic parts like resistors and transformers.

Also, on a ship of 400-odd crew, how is it possible that Captain Kirk does not have any knowledge of an attractive female astrobiologist, and so greets her in the transporter room with complete lack of recognition? The answer: it's not.

Transcript

1
Head Nurse's log, Stardate 4768.3. It began as a day like any other, Enterprise responding to a mysterious signal from omnipotent godlike aliens.
2
Sargon invited the captain, Dr McCoy, Mr Spock, and Dr Ann Mulhall to beam down. The captain pretended not to know Ann, probably to keep their off-duty liaisons discreet.
McCoy: 112 miles of solid rock?!
3
Sargon was, as Spock stated:
Spock: Pure energy; matter without form.
So is that energy or matter? I don't know.
4
Sargon's people destroyed themselves half a million years ago. Only the minds of Sargon, his wife Thalassa, and the male Henoch survived, trapped in glowing spheres.
Caption: It's Dr Pulaski! {pointing at Ann Mulhall}
5
They proposed switching minds with the captain, Ann, and Spock, to build android bodies to inhabit. I expect Harry Mudd's planet or the machine that duplicated my Roger could have done the job, but they insisted on making their own.
6
Sargon took the captain's body, placing his mind in the sphere. Thalassa occupied Ann. Henoch took over Spock; he complimented my appearance when he woke, which was... nice.
Spock: Hubba hubba!
7
I helped Henoch prepare a metabolic reduction drug to prevent their minds overloading the borrowed bodies. He told me something about Sargon's... but I can't seem to recall what...
Caption: Real drug {pointing at one hypo}
Caption: Placebo! {pointing at the other}
8
Sargon collapsed and the captain's body died, with the captain's mind still in the sphere. We revived the body mechanically, but couldn't transfer the mind.
9
Sargon had transcended matter entirely. He and Thalassa returned the captain and Ann's minds, but Henoch had fled and all the spheres had to be destroyed - including the one with Spock's mind!
10
We had to kill Henoch, in Spock's body. Dr McCoy had me get a hypo of poison. We confronted Henoch on the bridge. I didn't want to inject Spock's body, but something made me...
11
Henoch fled Spock's dying body, into oblivion. Sargon said deception was necessary to trick Henoch into believing Spock was dying - the hypo was harmless. Spock awoke, his mind returned!
12
Sargon had temporarily placed Spock's mind into me. Our consciousness had been shared! It was beautiful!
I only hope some day in the future Spock's body and mind are separated once more...