Genes and alleles?

Question

humans have 46 chromosomes, but does that mean only 23 of them have different genes? considering that the other 23 should be the same genes but different alleles.
i.e.
you get from your father
tallness (dominant) and brown hair (recessive)
from mother
shortness (recessive) and blonde hair (dominant)
that's 4 chromosomes, but they only determine 2 traits, height and hair color, and you ultimately end up being a tall blonde.

Also, during segregation of the alleles in self pollination, when the alleles separate during the formation of the gametes, do the traits separate randomly? or are they stuck to one type of sex cell?
ie (mendel)
a plant has the tall allele and short allele (Tt)
during self pollination, the allele splits (T) (t)
does it mean that the dominant allele will always be in "male" cells and recessive in "female" cells (or other way around)
or is it random, some male have dominant, some have recessive, and so forth?

thanks in advance.

Answer 1

We have 46 chromosomes or 23 pairs, 2 copies of each chromosome. We have around 100,000 genes (traits or chracteristics) that are on these 23 chromosomes. There are different versions of these genes which can be the same or different on the 2 different chromosomes in a pair (which is how we get our variation). How you get these genes and the combinations of genes is down to
1. independent assortment
2. crossing over (and mixing up the versions and combinations of genes)

THere are certain genes that actually are involved in several or many different genes (ie producing say a certain eye colour requires several genes working together). This is why scientists were surprised we didn't have more genes. They work in conjunction with other genes on the same or different chromosomes.
The combination of genes is up to chance!

in relation to your last part.....its the same as the first part. its random. But remember that hormones and "sex type" will also determine how tall you will be. males are genetically taller and maleness is only relying on 1 chromosome pair, but its enough to show the traits you are given. THe envrionment can also affect height (also in plants they are usually both male and female too!). People in japan are getting taller faster than some other places due to a reduction in the price of dairy food (which has always been expensive)....more calcium, better bone growth and taller people.
Hope this helps

Answer 2

i bought new jeans this weekend 38/32 Lee

Answer 3

are u sure some are not codominant? they might be but 4 the blonde and tallnes I think you are correct