Cell Physiology How do cells FUNCTION (work)? STERNGRR Processes take place at the cellular level! Cell Transport Photosynthesis Cell Respiration

Cell Transport is a STERNGRR process Lets food in for NUTRITION Lets oxygen in for RESPIRATION Lets waste out for EXCRETION Cell Transport Materials move in/out of cells through the cell membrane The cell membrane is SELECTIVELY PERMEABLE Phospholipid bilayer Membrane protein

Types of Cell Transport Passive Cell TransportActive cell transport Does NOT require energyRequires energy Movement DOWN the concentration gradient Movement AGAINST the concentration gradient High  LowLow  High

Diffusion is a type of Passive Transport Lets food in for NUTRITION Lets oxygen in for RESPIRATION Lets waste out for EXCRETION Diffusion Movement of molecules from a high to low concentration Example: Oxygen is moved from a high concentration in the lungs, to a low concentration in the blood Molecules move until they reach EQUILIBRIUM: An equal concentration on both sides of the membrane

Osmosis is a type of diffusion (a type of passive transport) Osmosis Movement of WATER molecules from a high to low concentration Example: In salt water, there is more WATER in the cell than in the surrounding environment, so water leaves the cells and they shrivel Molecules move until they reach EQUILIBRIUM: An equal concentration on both sides of the membrane

Cell Energy Processes include: Photosynthesis and Cellular Respiration Cell Energy Photosynthesis is a STERNGRR process Cellular Respiration is a STERNGRR process The two processes work together in a cycle!

Photosynthesis Involves making FOOD (sugar/glucose) for nutrition CO 2 + H 2 O + sun  C 6 H 12 O 6 + O 2 REACTANTS PRODUCTS Occurs in the CHLOROPLASTS of plant cells. Uses the green pigment CHLOROPHYLL to capture light energy Green light is reflected… all other wavelengths of light are absorbed by the plant.

Photosynthesis What is going in and coming out of the plant?

The food made in photosynthesis is used to make energy for cells! Food is NOT energy! They are 2 different things! ATP Plants make food for all living organisms (sugar) Organisms (including plants) must use this food to produce energy ATP is the energy molecule for cells Adenosine PPP Energy Energy is stored in a chemical bond – when the bond is broken, energy is released!

Cellular Respiration Involves using food made in photosynthesis for respiration, to make ATP for energy. C 6 H 12 O 6 + O 2  CO 2 + H 2 O + ATP REACTANTS PRODUCTS Occurs in the Mitochondria of ALL cells

Cellular respiration can take place WITH Or WITHOUT Oxygen! Cellular Respiration Aerobic respiration occurs when oxygen is present Anaerobic respiration (fermentation) takes place when oxygen is NOT present Makes a LOT of ATP Makes a little ATP In plants and microorganisms: Alcoholic fermentation In animals: Lactic acid fermentation