Why do children not exactly resemble their parents?
Since you've spoken about this in terms of chromosomes, I'm going to include some biology in my answer because it sounds like you'll understand it. Normal human body cells have 23 pairs of chromosomes, so 46 chromosomes, known as 2n. Each member of a pair is from a different parent. In order for sexual reproduction to work the sex cells (sperm and eggs) must have 23 chromosomes, known as n so that they can fuse to make a cell that can grow to form a new person (has 2n chromosomes). The way that the sex cells divide in a process called meiosis and fuse together allows the new characteristics (known as phenotypes) to arise. First, the chromosomes replicate themselves to form something called chromatids. Then then line up the middle of the cell in their pairs, so there is one maternal and one paternal chromatid next to each other. (Think of how you were told to "make a crocodile" on outings as a child if that helps.) some chromatid pairs are so close to each other that they can "swap" genes in a process called crossing-over. This makes new combinations of genes in a chromosome, so is one factor in making the child different genetically. After this the chromatids are pulled apart to opposite ends of the cell and the cell divides into two. As they line up randomly a different combination of paternal and maternal chromatids is present in the new cells (so they contain a random mix of the chromatids), again mixing up the genes. These two cells now contain 23 chromatids each but these chromatids are replicated chromosomes. The chromatids line up in the middle of the cell again (not in pairs because they don't have a partner chromatid to pair up with any more) and are pulled apart from their centres so split to make two lots of 23 chromosomes. The cell splits making four cells with 23 chromosomes altogether. Again they have lined up randomly (with one side of a chromatid facing a random side of the cell). This affects what end of the cell they are pulled to, so what DNA the sex cell will contain. Meiosis is a really complicated process to imagine just using words so I'll add a video to the sources. Hope it helps.
Why do some children resemble in looks a grandparent or other family member more than their actual mother or father?
It is attributable to the random recombination of DNA. I look nothing like my father, for example (or his parents), and yet I bear a striking resemblance to my maternal grandmother. Before delving into Genetics, I just assumed that you received 25% of your DNA from each grandparent (but all the mitochondrial or cytoplasmic DNA from the maternal grandmother and her mother, going back thousands of years). But I was wrong. DNA testing has shown that a person can receive as much as 30% or more DNA from one grandparent. In the case of a male, there is always a bias towards one or both maternal grandparents, depending on whether or not the X-chromosome recombines (since as much as 3 to 4% of all DNA is X-linked, whereas the Y from the father, like the mitochondrial DNA, accounts for about 1% of all non-autosomal DNA). I have not had genetic testing done; however, based on expressed DNA (i.e., facial features), as well as linguistic and artistic aptitude which manifested themselves before nurture could intervene, so to speak, I think it only logical to believe that I did indeed inherit a significantly greater amount of DNA from my maternal grandmother than from the other three.
Why do some children resemble one parent more than the other?
Children are what best explained as an amalgamation of the genes of their parents. Now for each quality that a child possess both the parents contribute their copy. But there is small problem of dominant and recessive gene. For two genes for same quality one becomes recessive and one become dominant. And the dominant one gets reflected on the outside world more prominently.Now for thousands of such genes one can simply imagine the probability that the genes will decide to be half dominant from father's side and half dominant from mommy's side. Well it's nearly zero. And hence offspring tend to have more quality of one parent than the other.
Why do children look like their parents?
Ok, so, as you know, your body is made up of cells. Within each cell, there a nucleus and within the nucleus are the chromosomes. A chromosome is basically DNA, actually it's lots of DNA coiled around proteins. Each human cell has 64 chromosomes in it and it is these chromosomes that determine what you look like. So, where do your chromosomes come from...well, when sexual reproduction occurs 23 chromosomes come from the egg cell and 23 come from the sperm cell (unless something goes wrong). These egg and sperm cells are obviously from your parents. So, it is the transfer of chromosomes from your parents during reproduction that actually gives you your looks. This is why you look like your parents. It is the combination of recessive and dominant genes (in the chromosomes) from your parents that make you look unique.
Do you think children resemble their grandparents more than they do their parents?
Yes. Many diseases also skip generations; %My mother was a (type-1) Diabetic as was her grandmother.
Why do offspring resemble their parents?
Because when a mother and father reproduce, their genes get mixed together to make a child.Is the simplified version of biology at learned at school. Mothers and fathers have genes, and some of them are more dominant than others. Brown eyes are more dominant than blue which are more dominant than green and so forth, so it’s highly likely that the child of a brown/blue eyed couple will have brown eyes.Though genes are usually quite like lottery, but a bit less fun, and so that child may end up with blue eyes. And an even rarer luck of the lottery would be if someone (Usually a grandparent) had green eyes, then that child may end up with green eyes.But that’s what I’ve learned about it. Plus, I know things like obesity and mental disorders tend to run through families and that also contributes to people looking like their parents.
If a child more strongly resembles one parents physical traits than the other parents the explanation could be?
b...this is when the chromosomes line up
Is it possible for a child not to resemble either parents?
Sure, this can happen. As the others said...we get genes not only from our parents, but other family members too. My mom's sister had 9 children. None looked like each other or their parents. One of my cousins looked more like he was my brother.