Biology 2 Summary

Cellular Basis of Tissue and Cell Culture:

• Based on the principle of chromosome duplication and equal segregation during mitosis.

Photosynthesis Intensity:

• Plant leaves absorb all light wavelengths except green, therefore photosynthesis intensity is weakest in the green light region.

Analyzing Cross Results:

• Phenotype ratio of F1: 3:3:1:1 can be analyzed as (3: 1) x (1: 1).

• The 3: 1 ratio is the result of the cross Aa x Aa or Bb x Bb.

• The 1: 1 ratio is the result of the cross Bb x bb or Aa x aa.

Digestion and Exercise:

• Right after a main meal, if you engage in strenuous exercise, the blood flow to the digestive tract will decrease, affecting the process of food digestion.

Structure of mRNA:

• One mRNA molecule is synthesized based on the template strand of the gene, with the nucleotides T, A, X on the template strand corresponding to A, T, G on the complementary strand of the gene.

Gamete Ratio:

• Gene AaBbddEe produces abde gamete with a ratio of 1/8, calculated by the product of probabilities of each gene pair: 1/2 . 1/2 . 1 . 1/2 = 1/8.

Natural Selection:

• Natural selection is the main driving force behind evolution, eliminating less adapted individuals and preserving those that are more adapted to the environment.

Start Codon:

• In prokaryotes, the start codon for polypeptide synthesis is formylmethionine.

• In eukaryotes, the start codon for polypeptide synthesis is methionine.