Biology 2 Essay, Research Paper

BIOLOGY 2 1. ORAGANELLES2. TYPES OF CELLS3. OSMOSIS/ DIFFUSION4. CELL THEORY 1. ORGANELLES small structures embedded in the cytoplasm e.g. plastids, vacuoles, mitochondria, lysosomes, centrosomes, endoplasmic reticulum (e.r.) 2. TYPES OF CELLS A. Prokaryotic Cells  3.5 billion yrs old 1st organisms to exist in the biosphere a. Kingdom Eubacteria pathogenic (disease- causing organisms) unicellular photosynthetic, chemosynthetic anaerobic b. Kingdom Archaea Can be found in ocean vents, human intestine Not Photosynthetic, therefore heterotrophic (dependent on other organisms for food) Anaerobic B. Eukaryotic Cells ORGANELLE FUNCTION1. Endoplasmic reticulum (ER) – connects the nuclear membrane and cell membrane at several points2. Plastid – holds pigments3. Lysosomes – contains enzymes that promote the breakdown of organic compounds4. Microfilaments – cause cytoplasms to moveORGANELLES FUNCTION5. mitochondrion – center of respiration cells; release energy that supports cell activity

6. Centrioles – functions in cell reproduction; not found in plant cells7. Golgi Bodies/ Apparatus – rich in fatty materials; make up cell glands8. Ribosomes – rich in DNA molecules; sites where protein molecules are built 3. OSMOSIS/ DIFFUSION Osmosis- Diffusion of water molecules in a semi-permeable membraneDiffusion- the movement of molecules from a greater concentration to a lesser concentration EXPERIMENT:1. Osmosis – petri dish A : potato with water- petri dish B : potato with salt solution MASS DISH A (water) DISH B (salt water)Before 15.3 g 18.3 gAfter 15.5 g 17.1 gGained/lost mass gained lostMovement of water molecules Inward movement Outward movement 2. Diffusion- 50 mL beaker half-full of water (solvent: dissolving agent)- 2 drops of Potassium Permanganate (solute: substance being dissolved)- observe movement of molecules as they mix ***potassium permanganate mixed in a swirling, spiral motion it turned pinkish-purple and after a while, you could not distinguish solute from solvent (even distribution of molecules) 4. CELL THEORY1. All living things are made up of cells2. All cells come from pre-existing cells3. Cells are the fundamental unit of all living things