Answer:
A. Mendel observed green and yellow pea pods in a 3:1 ratio because the F1 generation was heterozygous.
Explanation:
The two true breeding plants in the parental population were homozygous (that is what true breeding means). Therefore, their cross would lead to all heterozygous offspring (see attached punnet square). Green is the dominant characteristic, so all F1 plants had a green phenotype, but Gg genotype.
The F1 cross would therefore be Gg x Gg. See attached punnet square.
The genotypes in the F2 generation are 1 GG: 2 Gg: 1 gg 1
Therefore, the phenotypic ratio is 3 green pea pods (Gg or GG): 1 yellow (gg)
Neurological - by nerves
Endocrinological - by blood and secrets
Answer:
Details about DNA are given in the explanation section. Hope it will be helpful for you.
Explanation:
DNA, or deoxyribonucleic acid, is the hereditary element in humans and almost all other organisms. Nearly every cell in a person’s body has the same type of DNA. Most DNA is found in the cell nucleus (nuclear DNA), but a small quantity of DNA can also be found in the mitochondria (mitochondrial DNA or mtDNA).
The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). Human DNA consists of about 3 billion bases, and more than 99 percent of those bases are the same type in all people.
DNA bases pair up with each other, A with T and C with G, to form units that are called base pairs. Each base is also attached to a sugar molecule and a phosphate molecule. A base, sugar, and phosphate are called a nucleotide. Nucleotides are arranged in two long strands that form a spiral called a double helix.
A valuable feature of DNA is that it can replicate, or make copies of itself. Each strand of DNA in the double helix can serve as a pattern for duplicating the sequence of bases.
Oil and water separate because they have different densities.