Ch.6 -Cell Processes And Energy
Standards:
7.LS1.8 - Construct an explanation demonstrating that the function of mitosis for multicellular organisms is for growth and repair through the production of genetically identical daughter cells.
7.LS1.9 - Construct a scientific explanation based on compiled evidence for the processes of processes of photosynthesis, cellular respiration, and anaerobic respiration in the cycling of matter and flow of energy into and out of organisms.
7.LS3.3 - Hypothesize that the impact of structural changes to genes (i.e., mutations) located on chromosomes may result in harmful, beneficial, or neutral effects to the structure and function of the organism.
7.LS3.2 - Distinguish between mitosis and meiosis and compare the resulting daughter cells
Important Vocabulary:
Food Chain - A series of events in an ecosystem in which organisms transfer energy by eating and being eaten.
Photosynthesis - The process by which plants and other autotrophs capture and use light energy to make food from carbon dioxide and water.
Autotroph - an organism that makes its own food; a producer
Heterotroph - an organism that cannot make its own food; a consumer.
Chlorophyll - A green photosynthetic pigment found in the chloroplasts of plants, algae, and some bacteria.
Cellular Respiration - The process in which oxygen and glucose undergo a complex series of chemical reactions inside cells, releasing energy.
Fermentation - the process by which cells release energy by breaking down food molecules without using oxygen.
Cell Cycle - the series of events in which a cell grows, prepares for division, and divides to form two daughter cells.
Mitosis - the second stage of the cell cycle during which the cell's nucleus divides into two nuclei and one set of DNA is distributed into each daughter cell.
Chromosome - A threadlike structure within a cell's nucleus that contains DNA that is passed from one generation to the next.
Summary
Nearly all living things obtain energy either directly or indirectly from from the energy of sunlight that is captured during photosynthesis. During photosynthesis, plants and some other organisms absorb energy from the sun and use the energy to convert carbon dioxide and water into sugars and oxygen. During cellular respiration, cells break down glucose and other molecules from food in the presence of oxygen, releasing oxygen. During fermentation, cells release energy from food without using oxygen. Cell division allows organisms to grow, repair damaged structures, and reproduce. During the cell cycle a cell grows, prepares for division, and divides into two new cells, which are called "daughter cells."
A heterotroph cannot make its own food and gets its energy by consuming other living things.
Autotrophs can produce their own food by capturing energy from sunlight or chemicals.
