IMG_1430.jpeg

# Biology Summary ## What are Genes? Genes are sections of DNA. ## What is a Genome? A genome is the totality of all genes, the genetic material. ## What are Chromosomes? Chromosomes are formed when chromatin condenses shortly before cell division. They are different sizes and have an X-shape...

# Biology Summary ## What are Genes? Genes are sections of DNA. ## What is a Genome? A genome is the totality of all genes, the genetic material. ## What are Chromosomes? Chromosomes are formed when chromatin condenses shortly before cell division. They are different sizes and have an X-shape. ## Differences and Similarities between Chromatin and Chromosomes Chromatin is a loose tangle of DNA, while chromosomes are the condensed form of chromatin. During cell activity, chromatin is active. Both chromatin and chromosomes consist of DNA and proteins containing genetic information. ## What are Chromosome Sets? These are double chromosomes. ## Stages of Mitosis The image shows a diagram of the five stages of mitosis: interphase, prophase, metaphase, anaphase, and telophase. **1. Interphase:** DNA replication occurs inside the cell. The cell grows and carries out its functions. **2. Prophase:** DNA condenses into chromosomes. The nuclear membrane breaks down. Chromosome pairs connect. **3. Metaphase:** The chromosomes line up in the center of the cell. Spindle fibers connect to the centromeres. **4. Anaphase:** The chromosomes separate and are pulled to opposite ends of the cell by spindle fibers. **5. Telophase:** A new nuclear membrane forms around each set of chromosomes. The chromosomes unwind. Two new cells are formed from one. **Key Processes in each stage:** * **Interphase:** DNA replication * **Prophase:** Chromosome formation, nuclear membrane breakdown, connection of pairs. * **Metaphase:** Chromosomes align in the center, spindle fibers attach to centromeres. * **Anaphase:** Chromosome separation, pulling to opposite poles. * **Telophase:** New nuclear membrane formation, chromosome unwinding. Two new cells are formed.