Molecular biology (Molecular Biology 5th (Fifth) Edition, Robert Weavers, amazon)

  1. all living things are grouped into 3 domains:
    1.1 bacteria 1.2 eukaryota 1.3 archaea

  2. Gene can exist in several different forms called allels (等位基因). Gene is the category, allel is the options under this category.
    2.1 recessive 隐性 2.2 dominant 显性 2.3 heterozygote 杂合子 2.4 homozygote 纯合子

GeneAllele
A gene is a short sequence of DNA encoding for a certain traitAlleles are different variants of a gene
Genes determine traits in an individualAlleles are responsible for diverse features of a given trait
A gene can have many different allelesAn individual contains a pair of alleles for a particular gene, which may be homozygous or heterozygous, dominant or recessive
Examples: skin, hair, or eye colourExamples: black, brown, blue, or green eye colour
  1. Gene exist in a linear array on chromosomes.染色体
  2. Traits are governed by genes.
  3. If traits lie on the same chromosome, these traits can be inherited together.
  4. Homologous 同源 chromosomes are pairs (diploid cells) of chromosomes, one inherited from each parent.
  5. Meiosis happens during reproduction.
  6. In humans, we have 2 broad categories of chromosomes:
    8.1 autosomes 常染色体, 22 different types.
    8.2 sex chromosomes, X and Y
  1. The farther apart two genes lie on a chromosome, the more likely such recombination between them will be.
  2. In the transcription step, RNA polymerase makes a messenger RNA, which is a copty of the information in the gene. In the translation step, ribosomes read the mRNA and make the protein.
  3. DNA adn RNA are chain-like moleculars, and they are made of subunites called nucleotides.
  4. The nucleotides contain a base linked to 1'-position(one prime position) of a sugar (ribose in RNA or deoxyribose in DNA) and a phosphate group.
  5. The phosphate joins the sugars in a DNA or RNA chain through their 5'- and 3'-hydroxyl groups by phosphodiester bonds.
  6. adenin, thymin, guanine, cytosine.
  7. Certain viruses contain genes made of RNA instead of DNA.