Biology Unit 2

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Across
  1. 4. All the solid parts of the Earth, from the surface to the core. This includes the crust, mantle, and core, as well as features like rocks, soil, mountains, and volcanoes.
  2. 5. An organism, such as bacteria, fungi, and earthworms, that breaks down dead organic matter and waste. This process recycles nutrients back into the ecosystem.
  3. 7. (Adenosine diphosphate)An organic compound essential for the flow of energy in living organisms. When adenosine triphosphate (ATP) releases a phosphate group to provide energy for a cellular process, it becomes ADP.
  4. 9. Pertaining to organisms or processes that require oxygen to live or function. Aerobic respiration, for example, is the process of generating energy in the presence of oxygen.
  5. 12. The green pigment found in the chloroplasts of plants, algae, and some bacteria. It is responsible for absorbing the light energy required for photosynthesis.
  6. 13. Requires oxygen. This process evolved after oxygen became abundant in Earth's atmosphere.
  7. 14. A specialized organelle in plant cells and some algae where photosynthesis occurs. It contains chlorophyll and is enclosed by a double membrane.
  8. 16. A metabolic pathway that breaks down glucose and produces ATP. It consists of three main stages: glycolysis, the Krebs cycle, and the electron transport chain.
  9. 18. Pertaining to organisms or processes that can function without oxygen. Some organisms are facultative anaerobes, meaning they can live with or without oxygen, while obligate anaerobes die in its presence.
  10. 19. An organism that cannot produce its own food and must consume other organisms or organic matter for energy. This category includes animals, fungi, and most bacteria.
  11. 20. (Adenosine triphosphate)Known as the "energy currency" of the cell, ATP stores and releases chemical energy to power most cellular activities. It consists of an adenosine molecule bonded to three phosphate groups.
Down
  1. 1. A series of chemical reactions in the mitochondrial matrix that releases stored energy by oxidizing acetyl-CoA. It produces ATP, NADH, and FADH₂.
  2. 2. A series of proteins and molecules embedded in the inner mitochondrial membrane. It accepts electrons from other steps of cellular respiration to create a proton gradient, which drives the synthesis of large amounts of ATP.
  3. 3. A metabolic process that occurs in the absence of oxygen, converting sugars into acids, gases, or alcohol. It allows glycolysis to continue producing ATP under anaerobic conditions.
  4. 6. (Light-independent reactions)Also known as the Calvin cycle, this set of reactions in the stroma of chloroplasts uses the ATP and NADPH from the light-dependent reactions to convert carbon dioxide into glucose.
  5. 8. All the water on Earth, including oceans, rivers, lakes, groundwater, ice, and water vapor in the atmosphere.
  6. 10. The sum of all ecosystems on Earth. It encompasses all living organisms and the areas where life is found, including portions of the atmosphere, geosphere, and hydrosphere.
  7. 11. A chemical element fundamental to all life. Its unique bonding properties allow it to form the backbone of all organic molecules, including carbohydrates, proteins, lipids, and nucleic acids.
  8. 15. The initial stage of cellular respiration, taking place in the cell's cytoplasm. It breaks down one molecule of glucose into two molecules of pyruvate, producing a small amount of ATP and NADH.
  9. 17. An organism that can produce its own food, using light or chemical energy. Plants are photoautotrophs that use photosynthesis, while some bacteria are chemoautotrophs.