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Section 2.9 Name: Question of the Day Section 2.9 Name: Question of the Day Review of Old Information: Things You Should Know 1. All organisms have a stable set of internal conditions they must maintain to survive, we call this ______________________. 2. There are two major types of cells that make up organisms. Organisms made of ______________________ cells have NO nucleus or organelles. ______________________ cells have both a nucleus and organelles. 3. Three organelles found in a plant cell and not an animal cell includes the _______________, ________________, and _________________. 4. Organelles are found in the cytoplasm of the cell. Organelles function within the cell much like organs function in our own bodies. 5. The mitochondria helps to produce _______________ within our cells, while the rough endoplasmic reticulum (ER) helps to transport and make __________________ through the cell. Ribosomes help to produce _________________ in the cell, and the golgi apparatus helps to modify and _________________ materials to be shipped out of the cell. Finally, _________________ help to digest old molecules and organelles. 6. Microtubules and microfilaments (cytoskeleton) help with the structure, shape, and movement of the cell. Some cells have short hair-like structures called __________ that help the cell to move, while others move using whip-like structures called ____________. 7. The cell membrane is referred to as _____________ ______________ because it only allows certain substances to pass through its lipid bilayer. 8. The two major components of the cell membrane are _______________ and _______________. 9. The fluid mosaic model states that the cell membrane behaves more like a __________ than a solid. 10. The cell membrane maintains _______________ by controlling what enters and leaves the cell. 11. There are two categories in which materials can be transported across the membrane: _______________ and _______________ transport. 12. During _______________ transport materials are naturally moved down the concentration gradient from a _______ to a _______ concentration. 13. _______________ transport requires the cell to use ATP (energy) to transport materials across the membrane. During this process, materials are transported _____ the concentration gradient from a _______________ to a high concentration. 14. One special type of passive transport is called in _______________, which is when water is transported across the membrane. In a ________________ solution, water will move into the cell and in some cases cause cytolysis (the bursting of the cell). In a ________________ solution, water will leave the cell and cause plasmolysis (the shriveling of a cell). In _______________ conditions, the cell is in equilibrium. 15. In ________________, the cell uses active transport to engulf and ingest materials from outside the cell. In _______________, the contents of a vesicle inside the cell are released outside of the cell. PART 1: Class Review 1. Label the three images below as isotonic/ hypertonic/ hypotonic (with regard to the solution the cell is placed in) 2. Movement across the cell membrane that does not require energy is called [ active / passive ] transport. 3. The difference in the concentration of a substance across a space is called a concentration [ equilibrium / gradient ]. 4. If there is a concentration gradient, substances will move from an area of high concentration to an area of [ equal / low ] concentration. 5. The cell membrane is [ selectively permeable / impermeable ]. 6. [ Equilibrium / Diffusion ] is the simplest type of passive transport. 7. The diffusion of water through a selectively permeable membrane is called [ osmosis / diffusion ]. 8. The direction of water movement across the cell membrane depends on the concentration of free water[ molecules / solutions ]. 9. A solution that causes a cell to swell is called a [ hypertonic / hypotonic ] solution. 10. Organelles that collect excess water inside the cell and force water out are called[ diffusion organelles / contractile vacuoles ] 11. The process of taking material into the cell by infolding the cell membrane is called [ endocytosis / exocytosis ] 12. In [ facilitated / molecular ] diffusion, membrane proteins help molecules across the membrane. 13. In diffusion, molecules [ spread out / condense ] 14. The lipid bilayer describes [ a type of transport / the cell membrane ] 15. Facilitated diffusion moves substances down their concentration gradient [ with / without ] using the cell's energy Explain what will happen to cells when placed in isotonic, hypertonic, and hypotonic solutions. PART II: Individual Review 1. Homeostasis refers to the a. Organization of cellular structures b. Stable level of internal conditions in organisms c. Organized structure of crystals d. Destruction of tropical rainforests 2. A prokaryote has a. A nucleus c. a cell membrane b. Membrane bound organelles d. all of the above 3. The major components of cell membranes are a. Lipids c. proteins b. Nucleic acids d. lipids and proteins 4. The function of the golgi apparatus is to a. Synthesize proteins b. Release energy c. Modify proteins for export d. Synthesize lipids 5. Mitochondria a. Transport materials b. Create energy in the form of ATP c. Make proteins d. Control cell division 6. Ribosome’s a. Transport materials b. Release energy c. Make proteins d. Control cell division 7. The nucleolus is a. The control center of the cell b. The storehouse of genetic information c. The site where ribosome’s are synthesized d. None of the above 8. Plastids a. Store pigments b. Store membranes c. Synthesize proteins d. Secrete proteins 9. One difference between eukaryotic and prokaryotic cells is that only a. Prokaryotic cells are surrounded by a cell membrane b. Prokaryotic cells have a nucleus c. Eukaryotic cells have genetic information d. Eukaryotic cells have membrane-bound organelles and a nucleus 10. The cell membrane a. Allows all substances to pass into and out of the cell b. Prevents all substances form passing into and out of the cell c. Is composed mainly of a protein bilayer d. Is composed mainly of a lipid bilayer 11. Cells that have a high energy requirement generally have many a. Nuclei c. flagella b. Mitochondria d. microfilaments 12. Short hair-like organelles that can move and may cover a unicellular organism or line the respiratory tract are called a. Chromatin strands c. cilia b. Flagella d. spindle fibers 13. What structure found in the onion cells observed in lab gave the cells their shape a. Nucleus b. Cell wall c. Golgi apparatus d. Mitochondria 14. Short hair-like organelles that can move and may cover a unicellular organism or line the respiratory tract are called a. Chromatin strands c. cilia b. Flagella d. spindle fibers 15. This is true of the structure of the plasma membrane: a. It is a double layer of protein molecules with phospholipid molecules randomly dotted through it b. It is single layer of phospholipid molecules c. It is a double layer of phospholipid molecules with protein molecules dotted in it. d. It is single layer of protein molecules with phospholipids dotted in it. 16. The fatty acid tail of a phospholipid that helps compose the lipid bilayer of the cell membrane is hydrophobic meaning a. It thrives in the presence of water b. It repels (is afraid) water c. It does not allow any substance into the cell 17. In class when a potato was placed in salt water the potato was in a. A hypertonic solution b. A hypotonic solution c. An isotonic solution 18. In class when a potato was surrounded by fresh water the potato was in a. A hypertonic solution b. A hypotonic solution c. An isotonic solution Matching: Write the correct letter in the blank after each numbered term. 19. _______Cell a. digests organelles 20. _______ER b. repeating subunits of DNA 21. _______Nucleus c. the basic unit of life 22. _______Lysosome d. stores DNA and produces RNA 23. _______Nucleotides e. cell highway, helps make proteins 24. The part of the cell that functions to maintain homeostasis relative to the cells environment is the a. Cytosol b. Golgi apparatus c. Nucleus d. Cell membrane 25. Ions channels aid in the movement of a. Molecules up the concentration gradient b. Carrier proteins within the lipid bilayer c. Ions across the cell membrane d. Water across the cell membrane 26. A cell must expend energy to transport substances using a. Cell membrane pumps b. Facilitated diffusion c. Ion channels d. Osmosis 27. Some cell engulf, digest, and destroy invading bacteria through the process of a. Exocytosis b. Phagocytosis c. Osmosis d. Cytolysis 28. Carrier proteins are important in a. Osmosis b. Endocytosis c. Diffusion d. Facilitated diffusion 29. The two major component of the cell membrane are a. Proteins and DNA b. Proteins and Lipids c. Mitochondria and Lipids d. Ribosomes and Lysosomes 30. Proteins that cross through the cell membrane are known as a. Peripheral proteins b. Integral proteins c. Phospholipids d. Hydrophobic Circle the answer(s) in the first three questions: 42. When the cell USES energy to move substances across its membrane, [passive, active] transport is occurring. 43. Passive transport moves materials [up, down] the concentration gradient. 44. Active transport move materials across the membrane from a [high, low] to a [ high, low] concentration. Match the following TYPES of passive transport with their descriptions: _____ 45. Diffusion a. movement of insoluble molecules through carrier proteins _____ 46. Osmosis b. molecules (like O and N) move DOWN concentration gradient _____ 47. Faciltiated Diffusion c. membrane proteins let molecules (like Na+ and K+) in and out of cell _____ 48. Ion Channel Diffusion d. diffusion of water molecules 49. If the molecular concentration of a substance is the same inside and outside the cell, the substance a. has a large concentration gradient. c. will undergo diffusion. b. is in equilibrium/homeostasis. d. will undergo osmosis. Circle the answer(s) in the questions below: 50. In HYPOTONIC conditions, water will move [ inside, outside ] the cell.
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