Important things I have learned so far in science
DNA
DNA is a complex, long-chained molecule that encodes the genetic characteristics of a living organism. In most plants and animals, DNA is packaged with ribonucleic acid and proteins into compact structures called chromosomes that reside in the cell nucleus.
DNA contains four basic building blocks called adenine (A), cytosine (C), guanine (G) and thymine (T)
Genetics
The human genome has 3 billion pairs of bases. The order of these nucleotides are critical to the accuracy of the instructions of a gene. The most important molecules encoded by genes are RNA and proteins. Gene – the functional and physical unit of heredity passed from parent to offspring.
Every cell in the body with a nucleus (a compartment in most cells) has the same complete set of genes. A gene is made of DNA (deoxyribonucleic acid) and is basically a type of genetic instruction. Those instructions can be used for making molecules and controlling the chemical reaction of life. Genes can also be passed from parent to offspring; this is inheritance.
Punnett square
The Punnett square is a square diagram that is used to predict an outcome of a particular cross or breeding experiment. It is named after Reginald C. Punnett, who devised the approach. The diagram is used by biologists to determine the probability of an offspring having a particular genotype.
If a mutation occurs in just one copy of the gene then that individual is considered heterozygous. On the other hand if both copies of a gene are mutated then that individual is homozygous genotype.
Dihybrid punnett square
Punnett, who devised the approach. The diagram is used by biologists to determine the probability of an offspring having a particular genotype. The Punnett square is a tabular summary of possible combinations of maternal alleles with paternal alleles.
A commonly discussed Punnett Square is the dihybrid cross. A dihybrid cross tracks two traits. Both parents are heterozygous, and one allele for each trait exhibits complete dominance. This means that both parents have recessive alleles, but exhibit the dominant phenotype.