Rio Salado BIO 156 Exam 2 Questions and Answers Solved 100% Correct!!

Rio Salado BIO 156 Exam 2 Cell Cycle - Answer -the collective series of intervals and events of a cells life, from the time it forms until it divides. What are the 4 intervals of interphase in the order they take place? - Answer -G1, G0, S, G2 What happens in interval G1? - Answer -this is when the cell increases in size and produces molecules required for DNA replication From which interval would a cell possibly go into interval G0 and how long would it stay there? What would it do there? - Answer -if a cell decided to go to G0 it would be after interval G1. Here it would just go about its metabolic business and not prepare to divide. It would stay there temporarily or permanently. If it decided to leave, it would go back to G1 and then progress on to interval S. What happens in interval S? - Answer -a cell copies it's chromosomes by DNA replication. After this happens each chromosome consists of two molecules of DNA and they are attached as sister chromatids. What happens in interval G2? - Answer -the cell produces proteins and other components that are necessary for division. Where does a cell go after interval G2 of interphase? - Answer -mitosis What do the built -in checkpoints do in interphase? - Answer -they stop the cycle from proceeding until certain conditions are met. What divides first, the nucleus or the cytoplasm? - Answer -Nucleus, then cytoplasm. What happens in mitosis? - Answer -the nucleus divides. What is cytokinesis? - Answer -division of the cytoplasm What is a centromere? - Answer -The centromere holds the sister chromatids together (made of protein) What is the first stage of mitosis and what happens there? - Answer -Prophase. The nuclear envelope breaks up, the centrosomes split up to opposite sides of the cell, spindle microtubules assemble and bind to chromosomes at the centromere. Think pro - pro a t breaking up What is a centrosome? - Answer -microtubule organizing center. they contain two centrioles. What is the second stage of mitosis and what happens there? - Answer -Metaphase. The chromosomes line up in the middle of the cell. Think meta - meet in middle. The centrosomes are still on opposite sides of the cell. What is the third stage of mitosis and what happens there? - Answer -Anaphase. This is where the centrosomes reach out with their microtubules and take one of each sister chromatid. There are now 4 chromosomes total. Think ana noooo What do microtubules do? - Answer -they are connected to the centrosomes and reach out to collect one of each chromatid. What is the last stage of mitosis and what happens there? - Answer -Telophase. Now that the chromosomes are all on opposite sides of the cell, they loosen up. Nuclear envelopes form around each cluster of chromosomes and mitosis ends. Chromosomes contain what? - Answer -DNA and proteins What are homologous chromosomes? - Answer -In a nucleus, chromosomes with the same shape, length, and genes What is the largest chromosome in humans, how many copies do we each have, and what are they considered? - Answer -Chromosome 1. We have 2. They are homologous chromosomes. What is the beginning cell called in both mitosis and meiosis? - Answer -the parent cell What are the cells formed by the parent cell in both mitosis and meiosis called? - Answer -the daughter cells