When the first kid starts crying because of the pain of the needle piercing through his/her body, all kids down the line start to cry and eventually, every kid on the line is crying even before they see the needle because they associate it with an illness

does this describe classical conditioning?

Explanation:

I'm not sure how to answer this so here's the phobia of needles: Trypanophobia

it´s related to his charming character.

beauty is not everything, although we can joke that girls only care about the physical or material aspect, the truth is that a real woman looks at more important things, besides intelligence and personality, there are other attitudes that make irresistible to men who are 'unattractive'.

for example develop your sense of humor.

explanation:

allergens: overstimulate the nerve system

neurotics: attack nerve cells

mutagens: damage or otherwise alter dna sequence

generators: cause defects during growth and development  

carcinogens: cause unchecked cell growth

i hope you get the idea according to me these are the effects that happened.