Can somebody explain chromosomes and genes to me?

Question

hi, can somebody help me out with this and tell me where/if i go wrong?

humans have 46 chromosomes (23 pairs) and you get 23 from your mother's egg and 23 from your father's sperm. it is done randomly so it is a lottery of which chromosomes the baby gets from which parent.

from this mixture of chromosomes, a person is produced, and the randomness involved means that two people from the same parents are going to have different characteristics based on which chromosomes they get?

so how do these chromosomes result in the millions of ways people are physically different from each other when there are only 46 chromosomes to choose from?

Answer 1

Each of those 46 chromsomes has many, many genes on them.  For example, human chromosome 1 has over 4,000 genes.  

The best estimates now for the total number of genes is 20,000-22,000.  And, many of those genes have multiple allele possibilities.  (Alleles are versions of a gene.)  During meiosis, the two copies of your mom's chromosome 1 exchange genetic information.  So, you're not getting one whole chromosome 1 from your mom, you're getting a whole chromsome 1 that is made up of pieces from both of your mom's.  The same thing is happening with your dad's chromsomes.  So, you're not getting a random shuffle of 46 chromosomes, you're getting a random shuffle of tens of thousands of genes.

In addition, the rapidly developing field of epigenetics is informing us that when genes are turned on and off can have a huge impact on the expression of each of these genes.

So, over 20,000 genes, two copies of each, many of which have multiple alleles, and the regulation (turning on and off) of these genes are what makes the infinite combinations.

Answer 2

All the answers are pretty good so far and I agree with everything they say.  I would also add that eggs and sperm are produced by Meiosis in which you can see the principle of Random Assortment.  Within Meiosis is a process called crossing over where bits of the two pairs of chromosomes in each parent are exchanged.  The net effect is that each chromosome you receive from your father is not like any chromosome in your father.  Rather it is a combination of your fathers two chromosomes

Answer 3

well the answer is that these 46 chromosomes contain quite a large number of genes on them which are actual hereditary material...chromosomes carry genes...so if millions of genes are present on one chromosome so think for yrself hw many combinations are possible..its the genes that decide the physical characters of individuals......chromosomes are like vehicles of inheritance and the genes are like riders..whereever the vehicle goes..the rider will also follow as it sits on the vehicle...out of these 23 pairs of chromosomes ..one pair is known as s*x chromosome coz it decides whether the individual is a male or a female and the other 22 pairs are known as autosomes which bear the genes responsible for somatic characters and general physiology of an individual......

Answer 4

You know that is a REALLY loaded question, right? *cracks knuckles*

You are right that we get 23 chromosomes from each parent but it is not random at all. The chromosomes are numbered 1 through 23 and you get a copy of each from each parent. Ex: one #2 chromosome comes from your mother and your other #2 chromosome comes from your father. If it was random, mutations would be much higher. A person could miss out on a chromosome (which is often fatal) or have an extra which can still be crippling such as Trisomy 21, Down's Syndrome.

The genes are located within one's chromosomes. There are over 25, 000 genes recorded in the human genome. Here's where it gets tricky you might want to do a little research on Punnett Squares. You have a copy of a gene... let's say for hair color. You have a copy from your mother, and a copy from your father. This is where dominance takes a role. Brown is dominant over blonde hair. So if your mother passed on the gene for blonde, but your father for brown, you will have brown hair. But you will still carry the gene for blonde. Thus if you have a child with a blonde mate, there is a chance that your offspring will be blonde, even though the recessive trait is masked in you.

Through inheritance, incomplete dominance, partial dominance, and recessive traits passed on without being exhibited, a lot of variation is possible. There is alot more to it than is listed here, this is just the tip of the iceberg...