Confusion about Aneuploidy/Polyploidy

[Justanotherhuman]

Hey there!
I didn't do 1/2 biology and the whole Aneuploidy/Polyploidy thing is seriously not sitting well in my head. So this question was in the 2010 bio exam, check it out!

So overall, there is the half looking chromosomes and like in 22 and 21 and then theres the full chromosomes like in 1. What is that implying? Initially I was thinking of 2 of the half chromosomes as 1 full chromosomes. Is that the right way to think?

The answer is trisomy, I drew "trisomy" out, and I don't see the correlation at all. What are the 1/2 chromosomes doing there (AHHHHHHHHHHH freaking out inside)
Do you have any recommendation as to how I can better understand this section of the study design. I have done no unit 2 work at all. I'm guessing I need to do more work on mitosis/meosis and karyotypes?
Any explanation would be amazing
Thankyou

[Justanotherhuman]

I cannot attach the 2 images (files are too large) check them here:
https://drive.google.com/drive/u/0/folders/12-xhBFmoiEZEAdiQI1kFv0aHXRsN05f8

[PhoenixxFire]

A lot of this isn't in the study design anymore. Only aneuploidy and polyploidy are (not mitosis/meiosis).

The relevant study design dot point

•    the qualitative treatment of the causes of changing allele frequencies in a population’s gene pool including
types of mutations (point, frameshift, block) as a source of new alleles, chromosomal abnormalities (aneuploidy
and polyploidy), environmental selection pressures on phenotypes as the mechanism for natural selection,
gene flow, and genetic drift (bottleneck and founder effects) and the biological consequences of such changes
in terms of increased or reduced genetic diversity

Aneuploidy occurs when an individuals has an unusual number of chromosomes (normally one more or one less). Trisomy means they have 3 copies of one chromosome (in this question, they have 3 copies of chromosome 15).
Polyploidy occurs when an individual has an unusual number of sets of chromosomes - for example if there were 3 copies of every chromosome then that would be polyploidy.

*You don't need to know the terminology below here*
21 & 22 aren't half chromosomes, chromosomes tend to get smaller as their number gets larger. Chromosomes can have their centers joined in different places, chromosome 1 is metacentric (joined in the middle, which is why it looks like an X), chromosomes 21 & 22 are telocentric (joined at the end, which is why they look like half an X).