gen bio chap1

• The ingredients for photosynthesis are carbon dioxide and water
• Oxygen gas is a by-product of photosynthesis
• CO2 is obtained from the air by a plant’s leaves
• H2O is obtained from the damp soil by a plant’s roots
• Cellular respiration is a chemical process that harvests energy from organic molecules.
• Cellular respiration occurs in mitochondria
• The waste products of cellular respiration, CO2 and H2O, are used in photosynthesis.
• aerobic process—it requires oxygen
• anaerobic process—it does not require oxygen
• Anaerobic processes can occur without oxygen but they do not produce as much ATP per glucose molecule as aerobic processes.
• common fuel molecule for cellular respiration is glucose
• Chemical reactions that transfer electrons from one substance to another are called oxidation-reduction reactions.
• The loss of electrons during a redox reaction is called oxidation
• The acceptance of electrons during a redox reaction is called reduction
• PLANTS NEED ENERGY TO PERFORM MANY ESSENTIAL FUNCTIONS OF LIFE: GROWTH, REPAIR, NUTRIENT MOVEMENT, REPRODUCTION, & NUTRIENT TRANSPORT.
• All of the reactions involved in cellular respiration can be grouped into three main stages: – Glycolysis – The Krebs cycle – Electron transport
• Glycolysis breaks a six-carbon glucose into two three-carbon molecules.
• A molecule of glucose is split into two molecules of pyruvic acid
• The Krebs cycle completes the breakdown of sugar.
• In the Krebs cycle, pyruvic acid from glycolysis is first “prepped” into a usable form, Acetyl-CoA
• Electron transport releases the energy your cells need to make the most of their ATP.
• The molecules of electron transport chains are built into the inner membranes of mitochondria
• Cellular respiration can “burn” other kinds of molecules besides glucose.
• Fermentation – The anaerobic harvest of food energy
• They have enough ATP to support activities such as quick sprinting for about 5 seconds
• Glycolysis is the metabolic pathway that provides ATP during fermentation.
• Pyruvic acid is reduced by NADH, producing NAD+, which keeps glycolysis going – In human muscle cells, lactic acid is a by-product.
• Yeast cells carry out a slightly different type of fermentation pathway – This pathway produces CO2 and ethyl alcohol.
• Glycolysis is a metabolic heirloom from the earliest cells that continues to function today in the harvest of food energy.
• PHOTOSYNTHESIS. From the Greek words: PHOTO = produced by light SYNTHESIS = a whole made of parts put together.
• PHOTOSYNTHESIS is the process whereby plants, algae, some bacteria, use the energy of the sun to synthesize organic compounds (sugars) from inorganic compounds (CO2 and water).
• What photosynthesis does: • Converts sunlight into stored chemical energy. • Makes carbon compounds that can be broken down for energy or used to build tissue.
• Photosynthesis is an endergonic process.
• Photosynthesis is endergonic because: Energy is consumed by the process.
• Carbon for making carbon compounds (such as sugar) comes from the atmosphere.
• Oxygen, hydrogen, and minerals are needed also. Oxygen and hydrogen come from water. Minerals comes from the soil
• Organic molecules are molecules that contain carbon AND hydrogen.
• The function of the chloroplast is to: Gather light energy and convert it to chemical energy.
• Light energy is “captured” by chlorophyl, which is embedded in the thylakoid membranes.
• Lightindependent reactions (C3 cycle) occur in stroma.