Question of the Day This organelle is the powerhouse of the cell A. Vacuole B. Golgi Apparatus C. Mitochondria D. Centriole 10/17/2015Template copyright

DOW NOW Oct 15 Discuss Chapter 7 Project – The Cell Booklet See Project Requirements Textbooks with you at all times. We will be using them throughout this chapter. 10/17/2015Template copyright

CELL BOOKLET PROJECT Organelle Pages 1. Ribosomes 2. Endoplasmic Reticulum 3. Golgi Apparatus 4. Lysosomes 5. Vacuoles 6. Mitochondria 7. Chloroplast 8. Cytoskeleton Include any other structures found within these organelles (Bold print Terms) 10/17/2015Template copyright

AGENDA Oct 15 BIG QUESTION: What is the cell theory? 1. QoD 2. DO NOW 3. Test 4. Begin Chapter 7 Section History of the Cell 6. Homework and Review 10/17/2015Template copyright

Chapter 7 Cell Structure and Function 10/17/2015Template copyright

7-1: The Cell Theory cells: the basic units of structure and function in living things discovery of the cell Anton van Leeuwenhoek –a Dutch biologist –invented the first microscope –studied drops of pond water and saw tiny living organisms 10/17/2015Template copyright

Robert Hooke (1665) –observed cork –saw tiny, rectangular chambers which he named cells –said plants only had cells Robert Brown (1833) –discovered the nucleus Matthias Schleiden (1838) –cell’s nucleus plays a role in reproduction Theodor Schwann (1839) –found animal tissues resembled plant tissue –said animals were made of cells Rudolf Virchow (1855) –animal and plant cells are produced only by the division of cells that already exist 10/17/2015Template copyright

The Cell Theory all living things are composed of cells cells are the basic units of structure and function in living things all cells come from preexisting cells 10/17/2015Template copyright

7-2: Cell Structure cells range between 5 and 50 micrometers in diameter cells remain small because: –physical limits on the flow of information and on the flow of material into and out of cell all cells have three basic structures: –the cell membrane: the outer boundary of the cell –the nucleus: control center of the cell –the cytoplasm: material between the cell membrane and the nucleus 10/17/2015Template copyright

10/17/2015Template copyright Cytoplasm area between the nucleus and the cell membrane fluid contains many important structures called organelles: tiny structures that performs a specialized function in the cell

10/17/2015Template copyright Nucleus controls the cell’s activities and contains DNA prokaryotes: cells without a nucleus –include bacteria eukaryotes: cells with a nucleus nuclear envelope: two membranes that surround the nucleus and contain nuclear pores »nucleolus: found in the nucleus and made up of RNA and proteins »makes ribosomes »chromosomes: found in the nucleus and contain the genetic information

10/17/2015Template copyright : Cytoplasmic Organelles 1. mitochondria: changes the chemical energy stored in food into compound that the cell can use –contain two special membranes 2. chloroplast: trap the energy of sunlight and convert it into chemical energy –only in plant cells and algae –structure similar to mitochondria –has a second membrane to change light energy into chemical energy reactions in both of these organelles are closely related

10/17/2015Template copyright Ribosomes structures in which proteins are made composed of RNA and protein some are attached to membranes some are found free in the cytoplasm smallest organelle made in the nucleolus

10/17/2015Template copyright Endoplasmic Reticulum complex network of sacs that transports material through the inside of the cell two types –smooth ER: does not have ribosomes attached –special enzymes and chemicals are stored here –rough ER: has ribosomes attached –synthesizes proteins

10/17/2015Template copyright Golgi Apparatus special compartments that modify proteins using special enzymes that attach carbohydrates and lipids looks like a flattened stack of membranes piled on top of each other modifies, collects, packages,and distributes molecules made at one location in the cell and used at another

10/17/2015Template copyright Lysosomes small membrane-bordered structures that contain chemical and enzymes necessary for digesting materials in the cell that are taken in through endocytosis engulfing materials that are too large to pass through the cell membrane formed by the golgi apparatus plant cells do not have lysosomes cell’s cleanup crew

10/17/2015Template copyright Vacuoles saclike structures that store materials such as water, salts, proteins, and carbohydrates plant cells have single large central vacuoles allows plants to grow quickly and gives extra support plastids: plant organelles that may take many forms one is the chloroplast involved in storage of food and pigments leukoplast: store starch granules chromoplasts: store pigments

10/17/2015Template copyright Cytoskeleton composed of a variety of filaments and fibers that support cell structure and drive cell movement microtubules: hollow and made of proteins provide support, help move organelles, and help in cell division microfilaments: long, thin fibers that function in movement and support help movement of cytoplasm called cytoplasmic streaming

Centrioles (See Cytoskeleton in your textbook) aid the cell in cell division arranges the microtubules of the cytoskeleton only found in animal cells found in pairs

7-3 Movement of Materials The Cell Membrane separates the cell from its surroundings regulates what enters and leaves the cell aids in the protection and support of the cell communicates with other cells, takes in food and water, and eliminates wastes composed of a double layer of lipids, known as a bilayer contain proteins act as channels through which molecules pass or pumps to push molecules through carbohydrates are also attached to proteins or lipids and act like identification cards 10/17/2015Template copyright

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Cell Wall cell structure that surrounds the cell membrane for protection and support found in plants, algae, and some bacteria very porous and allows water, oxygen, carbon dioxide, and other substances through made up of two or more layers –a gluey substance called pectin: helps hold the cells together –a fibrous material called cellulose: makes the wall elastic so it can stretch and grow –in plants that contain wood, there is lignin: makes cellulose more rigid 10/17/2015Template copyright

10/17/2015Template copyright Diffusion diffusion: process by which molecules move from areas of higher concentration to areas of lower concentration equilibrium occurs when the concentrations on both sides of the membrane are the same permeability determines which substances move across the membrane

10/17/2015Template copyright Osmosis diffusion of water molecules through a selectively permeable membrane pass through rapidly moves from an area of lower concentration to an area of higher concentration osmotic pressure: water pressure cells protect themselves with: cell walls bathing cells in blood contractile vacuoles to pump out water

10/17/2015Template copyright Facilitated Diffusion some molecules are too large to pass through cell membrane molecules too large must pass through a protein channel embedded in the cell membrane still driven by diffusion

10/17/2015Template copyright Active Transport requires energy allows material to move against a concentration difference two types: –carried through membrane- associated pumps (proteins) –large amounts of material are transported through movements of the cell membrane endocytosis phagocytosis: extensions of cytoplasm surround and engulf large particles pinocytosis: pockets form along the membrane, fill with liquid, and pinch off to form vacuoles exocytosis: the removal of large molecules from the cell

10/17/2015Template copyright Cell Specialization uniquely suited to perform a particular function within the organism two examples: light sensitive cells –packed with mitochondria –contains rhodopsin: a pigment that absorbs light street sweepers –special cells line lung passageways and release mucus –particles are trapped in mucus –have cilia

10/17/2015Template copyright : Levels of Organization cells: basic unit of life tissues: group of similar cells that perform similar functions organs: a group of similar tissues that perform similar functions organ systems: group of similar organs that perform similar functions –muscular, skeletal, digestive, circulatory, etc.