recombination question

A question that I'm sure someone here can answer for me:

In my basic understanding of genetic recombination, two chromosomes
recombine with crossings at essentially random locations in the DNA
sequence. Most of the crossing points, if selected randomly, occur in
long stretches of DNA that do not code for anything in particular, and
may well be junk for all we know. But the tiny bands along the
chromosome that contain genes are not vanishingly small and in fact
sometimes a crossing point must occur within a gene. When that happens,
if the two chromosomes have different alleles at that point in the DNA
sequence, the resulting gene will be a mash-up of the original two,
which I would guess is very unlikely to work.

My questions are:

does what I described actually happen or does something prevent
crossover within certain segments - and that's why genes have such
longevity?
If it does happen, what are the usual consequences? Does the individual
usually die?
How likely is it that a random crossover point in the DNA sequence falls
within a gene, rather than in the stuff between genes along the
chromosome?
How many crossover points do there tend to be per chromosome, roughly,
in human recombination?

as you can see I have only a very elementary understanding of this, I'm
a musician whose wife is taking elementary biology and I was just
looking at her textbook trying to understand this! Thanks for any
answers.

.

Relevant Pages

  • Re: Genomic Instability?
    ... is only one source of genetic variation. ... But even that is only part of the story since each chromosome ... As to the production of novel genes by recombination, ...
    (sci.bio.evolution)
  • Re: Mutations
    ... "Types of mutations: ... no effect and sometimes they alter the expression of some genes. ... This is known as tandem duplication. ... Duplicating only one chromosome is ...
    (talk.origins)
  • Chromosome transplant in mice could provide clue to Downs syndrome illnesses
    ... Chromosome transplant in mice could provide clue to Down's syndrome ... Scientists have successfully transplanted human chromosomes into mice, ... a string of about 250 genes. ...
    (alt.support.mult-sclerosis)
  • Re: What was a king anyhow? (was Re: Granada - king or Emir ?)
    ... as SRY and TDFY that are required to be male, ... differences in the Y chromosome. ... I am in no sense an expert, but the number of genes on the Y ... vs female with a Y). ...
    (soc.genealogy.medieval)
  • Re: Mutations
    ... "Types of mutations: ... no effect and sometimes they alter the expression of some genes. ... This is known as tandem duplication. ... Duplicating only one chromosome is ...
    (talk.origins)