AP Biology: Cells Latest Version with Complete Solutions

AP Biology: Cells Latest Version with Complete Solutions Active Transport Movement of solutes against a gradient, requiring the expenditure of energy Adhesion Proteins Attach cells to neighboring cells and give cell stability Anchoring Junctions Protein attachments between adjacent animal cells; desmosomes bind adjacent cells together and are associated with protein filaments that extend into the cell interior to hold structures together Bulk Flow Collective movement of substances in the same direction in response to a force or pressure Carrier Proteins Bind to specific molecules, undergo a change in shape, and then transfer the molecules across the membrane; i.e. the passage of glucose Cell Basic functional unit of all living things Cell Wall Provide support outside the plasma membrane; made of cellulose in plants; made of chitin in fungi Central Vacuole Large bodies in plant cells; exert turgor pressure on cell walls when full and maintain rigidity this way Centrioles and Basal Bodies Act as microtubule organizing centers (MTOCs); a centrosome outside the nuclear envelope gives rise to microtubules making the spindle apparatus in cell division; basal bodies are at the base of cilia and flagella and are made of nine triplets of microtubules Channel Proteins Provide open passageways through the membrane Chloroplasts Carry out photosynthesis to convert energy from sunlight into carbohydrates Chromatin Threadlike form of DNA Chromosomes Chromatin condenses during cell division into rod-shaped bodies Communicating Junctions Allow the transfer of materials; gap junctions between animal cells involve connexins which prevent cytoplasm from mixing but allow the passage of ions and small molecules; plasmodesmata between plant cells involves with a desmotubule surrounded by cytoplasm and plasma membrane going between the two