Energy and Life Chapter 8 Biology

Energy= the ability to do work Chemical Energy: stored in molecules and compounds (found in the food web) Light Energy: given off by the sun Metabolism (a characteristic of life) is the use of this energy to survive Remember: energy cannot created or destroyed, only transferred!

Basic Rule of Chemistry When you “make a bond” (build something), you store energy! When you “break a bond” (break something down), you release energy! Both methods are used in organisms to survive!

Photosynthesis Build molecules to store energy Knowing energy can only be transferred, trace the flow of energy for photosynthesis. Light Energy  Chemical Energy Autotroph: organism that uses energy from sunlight to create organic compounds (food)

Cellular Respiration Break down molecules to release and use energy Similar to the burning of fuel! Knowing that energy can only be transferred, trace the flow of energy for cellular respiration. Chemical Energy (Glucose)  Chemical Energy (ATP) and Thermal Energy Heterotroph: organisms that obtain energy from organic compounds

How does this energy transfer happen? Occurs in special organelles in cells Which ones? Chloroplast and Mitochondria ATP is created by transferring energy ATP acts as currency or gasoline for cells ATP is broken to release energy for cell processes (guess one!) ADP is then recycled back into ATP to be used again!

ATP Structure

ATP and Energy When ATP is broken down, it releases energy ATP  ADP + P + energy Can ADP be used again? YES! It is recycled…