Unit 3 Exam Review (5A, 5D) 5A Describe the stages of the cell cycle, including DNA replication and mitosis, and the importance of the cell cycle to the growth of organisms. 1. What is the main purpose of cell division? For the growth and repair of tissue 2. What are the three main phases of cell division? Interphase, mitosis, and cytokinesis 3. What is the outcome of mitosis? *be sure to describe the # of cells w/ parent & daughter & # of chromosomes in parents & daughter the outcome of mitosis is 2 identical daughter cells, each with the exact same number of chromosomes as the parent cell 4. If a parent cell had 6 chromosomes, how many chromosomes would each daughter cell contain? 6 5. Describe the three different phases of interphase: G1, S, G2 G1—first gap, normal growth, proteins & organelles are produced S—synthesis, DNA is replicated G2—second gap, more growth, the cell prepares for division 6. Label the following pictures of cells with their correct phases:
Interphase
Anaphase
Prophase
Telophase
Metaphase
Cytokinesis
7. Describe the four different phases of mitosis: prophase, metaphase, anaphase, telophase Prophase—chromosomes condense, nuclear membrane dissolves, nucleolus disappears, and centrioles moved to the opposite ends of the cell, spindles form Metaphase—spindles attach to chromosomes at the centromere and line up the chromosomes in the equator of the cell Anaphase— spindles shorten and pull the sister chromatids apart and towards the opposite ends of the poles Telophase—new nuclear membrane forms around the chromosomes, spindles disappear and the nucleolus reappears 8. Describe what is happening in cytokinesis. Cytoplasm dividing and 2 new cells are formed 9. Describe what happens to a cell in the G0 phase. G0 is a resting state after G1. no division occurs during G0.
5D Recognize that disruptions of the cell cycle lead to diseases such as cancer. 10. Describe how/why a cell is considered cancerous. Cancer cells divide uncontrollably and do not enter G0. 11. How are checkpoints important in normal cell division? Checkpoints allow a normal cell to verify that all the processes needed at a particular stage have been completed. If a cell has not completed (ex: DNA damage, irregular cell size) the process properly the cell will usually self destruct. 12. How is a tumor formed? As cancer cells begin to divide uncontrollably they form lumps of cells or tumors. 13. How does a cancer cell spread from one part of the body to another? A cancer cell can metastasize by breaking off from a mass of cancer cells and entering the blood stream. The blood stream then carries that cancer cell to another part of the body where it breaks off and divides.
