Building blocks of life
Part 1: Mitosis and Meiosis Short-Answer Response
Why are the process of mitosis and meiosis both important to a living organism?
The process of mitosis and meiosis are both important to a living organism because without them a cell would not be able to reproduce. Mitosis is an asexual process used to replace old and dead cells with new ones by dividing into two identical daughter cells. Meiosis, however, is the step that makes sexual reproduction possible by taking a cell (diploid) and splitting it into two daughter cells (haploid) containing only half of the homologous pair.
When would an organism need to undergo the process of mitosis? Meiosis?
Mitosis is the process a cell goes through in order to replace damaged or dead cells with new cells; these cells would be identical to each other as well as the parent cell. Therefore, an organism would need to undergo mitosis during its growth and development and when it needs to repair a wound or injury. Meiosis is the process a cell goes through in which it divides each cell by exactly one-half of the parent cell. An organism would undergo this process before reproducing in order to prepare for fertilization.
What would happen if meiosis did not occur?
If meiosis did not occur reproduction would not be possible. During this process a cell gets divided into one-half of the parent cell, which means that the cell contains one-half the DNA that an organism needs. Without this process the other half would not have anything to combine with to complete the DNA required to create a new cell. This would mean that reproduction of a new cell would not occur and the whole process would not be possible.
Part 2: Photosynthesis and Cellular Respiration Matrix
Complete the matrix. Use the following questions to aid in completion:
• What is the purpose of this pathway?
• Reactants: What does this reaction need to proceed?
• Products: What is produced because of the reaction?
• The role of ATP: Does it supply energy or store energy?
Cellular respiration Photosynthesis
Pathway Glycolysis Krebs cycle Electron transport Light-dependent reaction Light-independent reaction
Purpose Splits sugar Completes the process of breaking down glucose Transfers hydrogen Provide energy for the light-independent reaction Makes sugar
Where it takes place Cell cytoplasm Mitochondria Mitochondria Chloroplasts Chloroplasts
Reactants Six-carbon sugar, glucose Two three-carbon, hydrogen atoms NADH Chlorophyll, sunlight ATP, carbon dioxide, and NADPH
Products 2 three-carbon compounds Carbon dioxide and ATP ATP ATP, oxygen Carbohydrates
The role of ATP Supplies energy used for the next stage Supplies energy needed by the next stage Energy is captured to convert oxygen to water Transports solar energy in the form of ATP to power other chemical reactions Supplies energy needed to make carbohydrates