Anchor Text - Capitalizations? On-Site SEO - Bold and Italic?

I had a couple of questions that I've done admittedly just a little research on. People didn't seem like they could converge on an opinion, so I ask here.

Say perhaps I'm trying to use "apples" as my anchor text. That's the phrase I've done my research on, etc. If I use "Apples" as my anchor text, does the difference in capitalization matter? I did some google searches related to the real phrase I'm talking about and saw little variation in the results. What I did notice was that when I search "apples" in plural, Google returns me results that also include "apple" in the singular.

So that leads to another question... Will using anchor text for long tail keywords also include juice for the main keyword. For example, I want "apples" but I use the anchor text "apples are tasty." Does the long tail one lend power to both the long and short?

Also, what are your opinions on Bold and Italic as forms of on-page SEO for your keywords? Some say it doesn't matter at all, some say its so insignificant it doesn't matter, and others think its well worth the time. What are your opinions?

Thanks for your time.