Meley, Alex, Eli, Chris C. Chapter 2 Summery and Jeopardy Questions2.1 Cell theory 3 laws of the cell theory are cells are the smallest units of life, come from pre existing cells, allorganisms are composed of one or more cells. Use microscopes to view cells, by Robert Hookwho was the first to view cells in 1665. All organisms are either multi cellular or unicellular. Theyall carry the function of life which is metabolisms, growth, reproduction, response, homeostasis,and nutrition. These functions tie together to produce a function living unit. Organelles,bacteria, viruses, membranes and molecules range from sizes of cells can be from biggest tosmallest. The surface area to volume ration limits the size of cells. Reproduction of cells helpsthem replace damage cells or dead cells. Stem cells can’t divide and differentiate into differentcell type2.2 Prokaryotic CellsProkaryotic are usually smaller and simpler then eukaryotic cells. Prokaryotic Cells range from 1micrometer in diameter or less. Features are cell walls, plasma membranes, flagellum,ribosome, and nucleoid. The cell wall protects the membrane and shapes the cell. Cell walls aremade up of carbohydrates and protein complex called peptidoglycan. Plasma membranecontrols the movement of materials. The most visible structure in the microscope. Pilli andflagellum grow outside the cell wall and allow cell movement, Ribosome are the sites of proteinsynthesis. The nucleoid region contains a single long circular thread of DNA. Involves in cellcontrol and reproduction. Binary fission is the process by which the prokaryotic cells divide.
Meley, Alex, Eli, Chris C.2.3 Eukaryotic CellsEukaryotic cells range from 5-100 micrometers in diameter. Common organelles areendoplasmic reticulum, ribosome, lysosomes, Golgi apparatus, mitochondria, nucleus,chloroplast (only in plants and algal cells) centosomes, and vacuoles. Endoplasmic Reticulumconnects with the plasma membrane and connects with the nucleus membrane. Can be smoothor rough. Ribosome manufactures proteins and be found in the Cytoplasm and ER. Cytoplasmcontains cell organelles. Nucleus contains most of DNA. Mitochondria is their energytransformer. Vacuole storages hydrolytic functions. Lysosomes are intracellular digestivecentries that arise from the Golgi apparatus. Break down materials and are acidic. Chloroplastonly occurs in algae and plant cells. Contains its own DNA. Centrosomes are only found ineukaryotic cells and evolve from assembling from microtubules. Microtubules are important forcell division. Similarities between Eukaryotic and Prokaryotic both carry out the function of life,DNA is present in both cells.
Meley, Alex, Eli, Chris C.2.4 Membrane structure-phospholipids:”the backbone” is a bilayer produced from huge numbers of molecules calledphospholipids. Each phospholipid is composed of 3 carbon compounds called glycerol two ofwhich have fatty acids attached and the third has a highly polar organic alcohol that includes abond to a phosphate group.fatty acids are not water solubale because they are non poloar. Thisstructure means that the membrane has two distinct areas one is hydrophilic and the other areais not water solubale and is reffered to as hydrophobic.-cholesterol: at various locations in the hydrophobic region in animal cells are cholesterolmolecules. These molecules have a role in determining membrane fluidity which changes withtemperature. The cholesterol molecules allow effective membrane function at a wider reange oftemperatures.-protiens: the last major components of cellular membranes are proteins. Proteins createextreme diversity in membrane function. Proteins of various types are embedidn in the fluidmatrix of the phospholipid bilayer. There are usually two major types of proteins integralproteins peripheral proteins. Integral protines have both hydrophobic and hydrophilic regions inthe same protein and the peripheral proteins do not protrude to the middle of the hydrophobicregion but remain bound to the surface of the membrane.-membrane protein functions :· Hormone binding sites· Enzymatic action· Cell adhesion· Cell to Cell communication· Channels for passive transport· Pumps for active transport.
Meley, Alex, Eli, Chris C.passive and active transport· Passive transport does not require energy· Active transport does require energy-diffusion: is a type of passive transport particles move from high concentration to lowconcentration however in a living system diffusion often involves a membrane-facilitated diffusion: is a diffusion involving a membrane with specific carier proteins that arecapable of combining in a substance to aid in its move ment-Osmosis: is another type of passive transport where movement occers alon g a concentrationgradient Osmosis involves only the passive movement as water molecules across a partiallypermeable membrane. A partially permeable membrane is one that allows only certain things topass trhough .-sodium potassium pump: this mechanisim for actively moving sodium and pottasuim ions-1. Proteins bind to three intracellular sodium ions2. Ions cause phosphorolation by atp3. Causes change in shape thus expelling sodium ions4. Two extracellular bind to different regions of the proteins and cause the release of thephosphate group5. Loss of the phosphate group restores the protein to its original shape causeing the releaseof the potassioum ions into the intracellular space-endocytosis and excocystocsois:the endocytosis occurs when a portion of plasma membrane is pinched of to enclose macromolecules of particulates.Excosytosis is esentiially the reverse of endocytosis the fluididty of the plasma membrane andthe hydrophobic and hydrophilic properties of its molecules are just as important as endocytosis2.5 Cell DivisionsCells cycles describe the behavior of cells as they grow and divide. There are phases in celldivision. 2 types known as mitosis and meiosis. Interphase is the largest part of the cell cycle and
Meley, Alex, Eli, Chris C.the longest. 3 phase in interphase G1 , S , and G2. G1 is the major growth of the cell that takesplace. S is the main activity for replication in DNA. G2 is the second growth phases in the cell.Organelles can increase in numbers in G2.Four phases in mitosis, prophases, metaphases, anaphases, and telophase. Prophase chromatinfibers form chromosomes, the nucleoli disappears. Mitotic fibers begin to form.Centromeresattach the symbols and pull towards opposite pulls.Metaphases: chromosomes line up in the middle of the equator.Anaphases: the sister chromatins begin to splitTelophases: nuclear membranes begin to form and he spindle fibers begin to disappear, cellgoes to a stage of cytokinises.Cytokinesis is when the cells divide into two.Jeopardy questions:1) Which one is bigger Eukaryotic or prokaryotic?2) Explain the Cell theory3) Whats the difference in Stem Cells?4) What is facilitated diffusion?5) Outline the process of endocytosis and exocytosis