28 terms

Ch 2 Cell Processes and Energy

process by which a cell captures energy in sunlight and uses it to make food
organism that makes its own food
organism that cannot make its own food; obtains food from other organisms
2 Stages of Photosynthesis
chloroplasts (green) capture the energy in sunlight; use the energy to make food and oxygen
colored chemical compounds that absorb light
the main photosynthetic pigment in chloroplasts; captures light energy and uses it to power 2nd stage
small openings on the underside of leaves; how carbon dioxide enters and oxygen leaves
photosynthesis equation
6CO2 + 6H2O + light energy → C6H12O6 + 6O2
process by which cells obtain energy from glucose; cells break down simple food molecules such as sugar and release the energy they contain; energy stored in form of carbohydrates, break them down when energy is needed
2 Stages of Respiration
1. in cytoplasm - molecules of glucose broken down into smaller ones, oxygen not needed, not a lot of energy released. 2. in mitochondria - small molecules broken down into even smaller ones, oxygen used, lots of energy released
respiration equation
C6H12O6 + 6O2 → 6CO2 + 6H2O + energy
energy-releasing process that does not require oxygen; doesn't release a lot of energy
alcoholic fermentation
when yeast and other single-celled organisms break down sugars; products = alcohol, CO2 and little energy; CO2 makes air pockets in bread making it rise; also cause of bubbles in alcohol
lactic acid fermentation
in the muscles; when they use up more oxygen than can be replaces - fermentation takes place, producing lactic acid, makes it weak and sore.
cell cycle
the regular sequence of growth and division that cells undergo; the cell grows, prepares for division, and divides into two new daughter cells
first stage of cell cycle; the cell grows, replicates DNA, and prepares for division; produces the structures it needs for division
process by which a cell makes a copy of the DNA in its nucleus
2nd stage in which the cell's nucleus divides into two new nuclei; one copy of DNA is distributed into each daughter cell
1st phase of mitosis; chromotin straighten (rod-like) and begin pairing to form chromosomes, nuclear membrane disappears, centrioles begin to move to poles
2nd phase; chromosomes line at equator, centrioles at poles, spindle fibers join the centromere of chromosome
3rd phase; chromosomes move to opposite poles by spindle fibers, grouping together in two parts, cell begins to cleave.
4th phase; nuclear envelope reforms, centrioles move back to poles; cell almost split
a double rod of condensed chromotin held together by the centromere; contains DNA that carry genetic info
cytoplasm pinches together around middle of cell and cytoplasm divides; two identical daughter cells, each has half the cytoplasm and half the organelles
disease in which cells grow and divide uncontrollably, damaging the parts of the body around them; begins when something damages a portion of the DNA in a chromosome
a change in DNA or a chromosome
a mass of abnormal cells that develops when cancerous cells divide and grow uncontrollably
the use of drugs to treat a disease; carried through through the body by the bloodstream; they kill cancer cells or slow down their growth