Is it true that father side has a stronger "heredity"?

[kenny1999]

My mum has two sisters, all of their kids (so my cousin) look so much alike their father, and of course, their fathers are not blood related to my sister and me so our cousins don't look like us at all. On the other hand, my father also has two brothers, and his brother's daughter looks so much like my sister. I have this question in my mind for a long time, it's not subjective opinion, everyone said that and everyone will immediately find that.

[Sensei]

Scientists use DNA tests..

 

[Genady]

Can you find a better reference than 

41 minutes ago, kenny1999 said:

everyone said that and everyone will immediately find that

?

In my life, nobody ever said that and nobody ever found that.

[Peterkin]

As to the title question : No. People are more likely to resemble the parents who has the most dominant genes. How much more likely depends on the presence of recessive genes in both parents. The only thing always determined by the father's chromosomes  is the sex of the offspring. Their appearance depends on a large number of quite random factors. 

[Genady]

Actually, a child receives more DNA from the mother than from the father.

[Peterkin]

1 hour ago, Genady said:

Actually, a child receives more DNA from the mother than from the father.

Because the X chromosome is bigger than the Y?  But the metabolic enzyme and brain function information on the X chromosome wouldn't show up in physiognomy ? 

[mistermack]

15 minutes ago, Peterkin said:

Because the X chromosome is bigger than the Y?

 No, it's because you get all of your mdna from your mother.

[Genady]

Yes, mitochondrial DNA comes only from mother.

[CharonY]

16 hours ago, Peterkin said:

Because the X chromosome is bigger than the Y?  But the metabolic enzyme and brain function information on the X chromosome wouldn't show up in physiognomy ? 

 

13 hours ago, Genady said:

Yes, mitochondrial DNA comes only from mother.

Just to be clear, mitochondrial DNA is found within, well, mitochondria, as they have their own, separate DNA (look up endosymbiont hypothesis if interested in more details). Almost all our mitochondria are from the mother (present in eggs, though there are actually cases were some sperm mitochondria survive, so it is not 100% black and white).

Also with the XY chromosome, most of the translation happens from the X chromosome, the Y chromosomes has roughly 1/10th of protein coding genes compared to the X chromsome, if memory serves. In isolation, the Y chromosome is a bit of an odd beast, with a lot of repetitive regions, but as they carry less essential information, their loss is not necessarily lethal (but you cannot lose the X).

[Genady]

Another point to make clear is that while boys get the smaller Y from their fathers compared to the larger X for their mothers, girls get the equally sized X and X from both.

OTOH, in girls only one X is active, just like in boys. So, on this account, girls have one X while boys have one X and one Y. The active X in girls is either the one that came from the father or the one that came from the mother, randomly.

[Peterkin]

15 hours ago, Genady said:

Yes, mitochondrial DNA comes only from mother.

How does it affect physical appearance?

[Genady]

5 minutes ago, Peterkin said:

How does it affect physical appearance?

I don't know. However, I understand the OP question being about "heredity" in general. The appearance features described in the OP are only examples of what they could personally observe.

[Peterkin]

2 hours ago, Genady said:

I understand the OP question being about "heredity" in general.

Oh. In that case, I guess metabolic function counts as much as facial features. And while one can see which facial features came from which side of a family, metabolism and cell functions are so widely distributed that I'd guess it's impossible to tell how much of any individual's are dominated by which parent's set of genes, until an illness is traced to some hereditary flaw.

[ScienceStyled]

I'm quite certain that it varies between individuals... some have more prominent father hereditary, sure, but for some mommy is much more dominant.