Recombining DNA in reproduction

[entropy1]

I understand that DNA strands have two sides with amino acids, and that the amino acids connect to each other by being the opposite of each other (A-T, C-G). I also understand that the reproductory DNA of the organisms reproducing each consist of one side of each of the DNA strands, that recombine with the corresponding side of the other organism, yielding a complete DNA strand that is the DNA of the produced organism.

My question is: if half of the DNA strands of ma en pa recombine, it is not certain that they "fit" together, that each amino acid fits to the opposite amino acid, right? What am I getting wrong?

 

[Drakkith]

My question is: if half of the DNA strands of ma en pa recombine, it is not certain that they "fit" together, that each amino acid fits to the opposite amino acid, right? What am I getting wrong?

Each chromosome in your cells consists of 'homologous chromosomes', meaning that one half is from your mother and one half from your father. They contain the same genes in the same order, but may have different alleles for each gene. These are not joined at the level of base strands, but are two separate double-stranded DNA molecules joined together at the centromere. In other words, one 'arm' of each chromosome is from your mother and the other is from your father. This is how you can have different alleles of the same gene without worrying about the base strands not matching up.

During meiosis, which is the type of cell division that produces sperm and egg, a process called homologous recombination occurs, which swaps pieces of each chromosome arm with its homologous piece on the other chromosome arm. This creates new mixes of genes and is how different traits are passed on to each offspring and why you can have brown hair while your sister can have blond.

See here: https://en.wikipedia.org/wiki/Homologous_chromosome

 

[entropy1]

It just is so ingenious...

 

[phyzguy]

I understand that DNA strands have two sides with amino acids, and that the amino acids connect to each other by being the opposite of each other (A-T, C-G). I also understand that the reproductory DNA of the organisms reproducing each consist of one side of each of the DNA strands, that recombine with the corresponding side of the other organism, yielding a complete DNA strand that is the DNA of the produced organism.

My question is: if half of the DNA strands of ma en pa recombine, it is not certain that they "fit" together, that each amino acid fits to the opposite amino acid, right? What am I getting wrong?

The base pairs (A,T,C,G) are not amino acids. They are called nucleotides, and consist of a sugar backbone, a phosphate group, and a purine or pyrimidine base.