1 28 13 Part 1 Cells Continued A Transporting materials across membrane Passive Diffusion of very small particles no energy required Higher concentration to lower concentration Active Transport of particles against concentration grade requires Bulk Transport Moving much larger materials into or out of cell energy Endocytosis into cell Phagacytosis solid materials Pinocytosis liquid materials Receptor mediated endocytosis cells engulf specific particles Exocytosis out of cell Vesicle used to transport things in or out of cells B Attachment to other cells 3 primary connections between animal cells Tight junction Cells that need to be water tight Forms a water tight seal between cells Ex Small intestine Desmosomes Gap junctions Act like Velcro and fasten cells together Allows for movement and flexibility in tissue Act like secret passageways and allow materials to pass between cells Cardiac muscle cells in heart C Organelles Nucleus Largest feature of cell Control center for activities Stores genetic information ribosomal subunits are assembled Chromosomes Thin fiber of DNA which carry hereditary info Nuclear membrane two bilayers covered in pores that surround nucleus Endomembrane system Rough ER Covered in ribosomes Ribosomes protein making machines Smooth ER Synthesizes lipids and fatty acids pospholipids and steroids Detoxifies molecules such as alcohol drugs and metabolic waste products Golgi bodies Processes and packages proteins lipids and other molecules for export to other parts of organism Vesicles Lysosomes Transport things in or out of cells Cell s garbage disposal Digests and recycles cellular waste products and consumed material Mitochondria Acts as all purpose energy converters Harvest energy to be used for cellular functions D Cytoskeleton Acts as inner scaffolding of the cell Provides shape and support Controls intracellular traffic flow Enables movement Cilia and flagellum E Plant Cells Cell walls Vacuole Provide structural strength Increased water retention Provides some protection against insects and other animals Stores nutrients Retains and degrades waste products Accumulates poisonous materials contains pigments enables plants to attract birds and insects Provides physical support Chloroplast Site of photosynthesis Conversion of light energy into chemical energy Part 2 A Energy Types Kinetic Potential Energy of motion stored energy Chemical energy food glucose Laws of thermodynamics Cannot be made or destroyed only transformed Not 100 efficient some energy lost as heat ATP Andenosine triphosphate Can be used and recycled Cellular respiration attaches ADP to Pi from energy from breakdown of food Energy is released as a phosphate group and ejected from ATP B Cellular Respiration Oxygen sugar carbon dioxide water ATP Plants and animals have this process Uses food and oxygen Steps in aerobic respiration 1 glycolysis Breaking down of sugar Universal energy releasing pathway Takes place in cytoplasm Yields energy in form of ATP NADH produced carries electrons Energy spent 2 ATP Energy gained 4 ATP 2 kreb s cycle 1 A new molecule is formed 2 High energy electron carriers NADH are made and carbon dioxide is exhaled 3 Oxaloacetate is re formed ATP is generated and more high energy electron carriers are formed 3 electron transport Inside the mitochondrion material can lie in one of 2 places Intermembrane space Mitochondrial matrix lower energy level 1 At each step in electron transport chain electron falls to 2 At end of change electrons put back together with oxygen and hydrogen ions to form water 3 Energy is used to power proton pumps Pack hydrogen ions from the mitochondrial matrix into intermembrane space 4 Protons rush back into mitochondrial matrix with great kinetic energy which can be used to builed ATP Energy from fats carbs proteins enter process at different points Anaerobic respiration fermentation Oxygen lacking Pyruvate lactic acid Exertion without enough oxygen leads to burning cramps C Photosynthesis How plants get food Steps Photo reactions 3 inputs 2 products sunlight water carbon dioxide oxygen sugar Occur in thylakoids of leaves chloroplasts Electron transport Split water Synthesis reactions The calvin cylce Capturing light energy Carbon dioxide taken into plant and used to build sugar Kinetic energy in form of waves Plants produce several different light absorbing pigments Each photosynthetic pigment absorbs and reflects specific wavelengths Seasonal differences in the amount of pigment molecules present in leaves lead to leaves changing color