Chapter 3: Cell Structure and Genetic Control (Review). Table 3 Chapter 3: Cell Structure and Genetic Control (Review). Table 3.1 page 52 Cell Cycle Apoptosis Cell Division: Mitosis Meiosis

Fig. 3.1 A generalized human cell showing the principal organelles.

Fig. 3.2 The fluid-mosaic model of the plasma membrane. The membrane consists of a double layer of phospholipids, with polar region oriented outward and nonpolar hydrocarbon oriented toward the center. Proteins may completely or partially span the membrane. Carbohydrates are attached to the outer surface.

Gene expression Genetic expression occurs in 2 stages: Genetic transcription: synthesis of RNA. Genetic translation: synthesis of protein. Genome refers to all of the genes in a particular individual or all the genes in a particular species. Genes are regions of DNA that code (through RNA) for polypeptide chains. Proteome refers to all of the proteins produced by the genome.

Fig. 3.14 The structure of the chromosome. Part of the DNA is wound around complexes of histone proteins, forming particles known as nucleosomes.

Fig. 3. 25 The life cycle of a cell Fig. 3.25 The life cycle of a cell. The different stages of mitotic division are shown; it should be noted, however, that not all cells undergo mitosis.

Apoptosis occurs normally as part of programmed cell death. Mitosis: Cell division in which the 2 daughter cells receive the same number of chromosomes as the parent cell (both daughters and parent cells are diploid). Occurs in somatic cells like the epidermis of the skin and the stomach lining. Meiosis: is a special type of cell division that occurs only in the gonads (testes and ovaries), where it is used only in the production of gametes (sperm cells and ova). It is called reduction division because the number of chromosomes is reduced from diploid in the parent cell into a haploid in the daughter cell.