To take "a" bite out of something often refers to literally biting and removing a piece of it.
When I wasn't looking she took a bite out of my hamburger.
One can figuratively take "a" bite out of something too, though this is less common.
McGruff the crime dog wants you to help him take a bite out of crime.
In this case, McGruff wants to reduce the number of crimes that are committed. In both cases we are reducing the quantity of something by taking a bite out of it.
To take "the" bite of something is almost always figurative. Jellyfish stings can feel like something is biting you, so you can "take the bite out" of them in various ways, including a mix of seawater and baking soda, which makes them less painful.
You can use "take the bite out" in many different contexts, with anything that feels like a sharp, biting pain -- physical, emotional, whatever.
In really cold weather like this you have to wear a warm hat to take the bite out of the freezing wind.
Actually it doesn't even have to be painful, just any strong sensation like an unpleasant odor or taste.
This curry is pretty spicy, but if you eat it with some of the yogurt sauce that'll take the bite out of it.
If we were to take "the" bite out of crime, we would be mitigating the negative effects of crime without necessarily reducing the number of crimes committed.
Synonyms for "take the bite out of"
Consider the sentence in two parts:
1. Reports are now coming in.
2. There is trouble at yet another jail.
Or look at it in a conversation:
"We're now getting a lot of reports."
"Oh, really? What do they say?"
"There's trouble at yet another jail."
In the sentence, of is used to indicate the reports' subject matter. Several different words could be used to express the same thing:
Reports are now coming in of trouble at yet another jail.
Reports are now coming in about trouble at yet another jail.
Reports are now coming in concerning trouble at yet another jail.
Reports are now coming in in relation to trouble at yet another jail.
Reports are now coming in on the topic of trouble at yet another jail.
Reports are now coming in that say there is trouble at yet another jail.
Syntactically, reports are not the same thing as trouble. It's like a bowl of ice cream. The bowl contains ice cream, but the bowl isn't the ice cream. You can't just remove of (without replacing it with something else) and have the phrase make sense.
Best Answer
To "take (something) out on someone" is an idiomatic expression that means "to be angry at someone for something that isn't their fault." For example, suppose I had a bad day at work and I come home and yell at my kids. Then someone could say that I am "taking it out on my children."
("Taking it out on someone" is, of course, unfair, but that's a different discussion)
"It" is a simple pronoun that means "your frustration with whatever is making you upset". It has no specific meaning but like any pronoun relates to something else previously stated, or implied by context.