1. CHAPTER 7 A TOUR OF THE CELL Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section B: A Panoramic View of the Cell 1.Prokaryotic and eukaryotic cells differ in size and complexity 2.Internal membranes compartmentalize the functions of a eukaryotic cell

2. All cells are surrounded by a ______________. The semifluid substance within the membrane is the __________, containing the ____________. All cells contain chromosomes which have genes in the form of DNA. All cells also have ___________, tiny organelles that make _________ using the instructions contained in _______. 1. Prokaryotic and eukaryotic cells differ in size and complexity Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

3. Cells are divided into two main types: ________ cells and _________ cells A major difference is the ________ of chromosomes. In a eukaryotic cell, chromosomes are contained in a membrane bound organelle, the _________. In a prokaryotic cell, the DNA is concentrated in the ____________ without a membrane separating it from the rest of the cell. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

4. Fig. 7.4 The prokaryotic cell is much simpler in structure, lacking a nucleus and the other membrane- enclosed organelles of the eukaryotic cell.

5. In eukaryote cells, the region between the nucleus and the plasma membrane is the ___________. All the material within the plasma membrane of a prokaryotic cell is cytoplasm. Within the cytoplasm of a eukaryotic cell is a variety of membrane-bounded organelles of __________________. These membrane-bounded organelles are _______ in prokaryotes. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

6. Eukaryotic cells are generally much ________ than prokaryotic cells. The logistics of carrying out metabolism set ________ on cell size. At the lower limit, the smallest bacteria, mycoplasmas, are between 0.1 to 1.0 micron. Most bacteria are 1-10 microns in diameter. Eukaryotic cells are typically 10-100 microns in diameter. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

7. The plasma membrane functions as a ___________ ____________ that allows passage of oxygen, nutrients, and wastes for the whole volume of the cell. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 7.6

8. The volume of cytoplasm determines the need for this exchange. Rates of chemical exchange may be _________ to maintain a cell with a very ______ cytoplasm. The need for a surface sufficiently large to accommodate the volume explains the microscopic size of most cells. Larger organisms do not generally have larger cells than smaller organisms - simply _____ cells. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

9. A eukaryotic cell has extensive and elaborate ________ _____________, which partition the cell into compartments. The barriers created by membranes provide different ________ ______________ that facilitate specific metabolic functions. The general structure of a biological membrane is a ____________ of __________ with other lipids and diverse proteins. Each type of membrane has a unique combination of lipids and proteins for its specific functions. For example, those in the membranes of mitochondria function in cellular respiration. 2. Internal membranes compartmentalize the functions of a eukaryotic cell Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

10. Fig. 7.7

11. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 7.8

12. CHAPTER 7 A TOUR OF THE CELL Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section C: The Nucleus and Ribosomes 1.The nucleus contains a eukaryotic cell’s genetic library 2.Ribosomes build a cell’s proteins

13. The ________ contains most of the _______ in a eukaryotic cell. Some genes are located in _________ and ____________. In the nucleus is a region of densely stained fibers and granules adjoining chromatin, the _________. In the nucleolus, ribosomal RNA (_______) is synthesized and assembled with proteins from the cytoplasm to form ribosomal subunits. 1. The nucleus contains a eukaryotic cell’s genetic library Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

14. Fig. 7.9

15. ___________ contain rRNA and protein. A ribosome is composed of two subunits that combine to carry out _______________ 2. Ribosomes build a cell’s proteins Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 7.10

16. Some ribosomes, ________ ribosomes, are suspended in the cytosol and synthesize proteins that function within the cytosol. Other ribosomes, _________ ribosomes, are attached to the outside of the ___________ ____________. These synthesize proteins that are either included into membranes or for export from the cell. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

17. CHAPTER 7 A TOUR OF THE CELL Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section D: The Endomembrane System 1.The endoplasmic reticulum manufactures membranes and performs many other biosynthetic functions 2.The Golgi apparatus finishes, sorts, and ships cell products 3. Lysosomes are digestive compartments 4. Vacuoles have diverse functions in cell maintenance

18. Many of the internal membranes in a eukaryotic cell are part of the ______________________. These membranes are either in direct contact with one another or are connected via transfer of _______, sacs of membrane. The endomembrane system includes the __________ _______, endoplasmic reticulum, _____________, lysosomes, _________, and the plasma membrane. Introduction Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

19. The endoplasmic reticulum (_____) accounts for _____ the membranes in a eukaryotic cell. There are two, albeit connected, regions of ER that differ in structure and function. ___________ looks smooth because it ______________. ___________ looks rough because ribosomes (bound ribosomes) are attached to the outside, including the outside of the nuclear envelope. 1. The endoplasmic reticulum manufactures membranes and performs many other biosynthetic functions Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

20. Enzymes of smooth ER synthesize ______, including oils, phospholipids, and steroids. The smooth ER also catalyzes a key step in the mobilization of _________ _____________________. Other enzymes in the smooth ER help ______ drugs and poisons. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 7.11

21. Rough ER is especially abundant in those cells that secrete proteins. These secretory proteins are packaged in ________ ________ that carry them to their next stage. Rough ER is also a ________ factory. Membrane bound proteins are synthesized directly into the membrane. Enzymes in the rough ER also synthesize membrane phospholipids from precursors in the cytosol. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

22. Many transport vesicles from the ER travel to the _____________ for modification of their contents. The Golgi is a center of manufacturing, warehousing, _______, and ____________. The Golgi apparatus is especially extensive in cells specialized for secretion. The Golgi apparatus consists of flattened membranous sacs - _________ - looking like a stack of pita bread 2. The Golgi apparatus finishes, sorts, and ships cell products Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

23. Fig. 7.12

24. The ________ is a membrane-bounded sac of _________ enzymes that ________ macromolecules. 3. Lysosomes are digestive compartments Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 7.13a

25. Lysosomal enzymes can hydrolyze proteins, fats, polysaccharides, and nucleic acids. These enzymes work best at _______. While rupturing one or a few lysosomes has little impact on a cell, massive leakage from lysosomes can destroy an cell by _________________. The lysosomes create a space where the cell can digest macromolecules _______. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

26. Fig. 7.13b Lysosomes can fuse with food vacuoles, formed when a food item is brought into the cell by ________________. As the polymers are digested, their monomers pass out to the cytosol to become nutrients of the cell. Lysosomes can also fuse with another organelle or part of the cytosol. This recycling, or __________, renews the cell.

27. Vesicles and vacuoles (larger versions) are membrane-bound sacs with varied functions. ____________, from phagocytosis, fuse with lysosomes. _______________, found in freshwater protists, pump excess water out of the cell. _______________ are found in many mature plant cells. 4. Vacuoles have diverse functions in cell maintenance Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

28. Fig. 7.15

29. CHAPTER 7 A TOUR OF THE CELL Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section E: Other Membranous Organelles 1.Mitochondria and chloroplasts are the main energy transformers of cells 2.Peroxisomes generate and degrade H 2 O 2 in performing various metabolic functions

30. Mitochondria and chloroplasts are the organelles that convert energy to forms that cells can use for work. _____________ are the sites of _________________, generating ______ from the catabolism of sugars, fats, and other fuels in the presence of oxygen. ___________, found in plants and eukaryotic algae, are the sites of ____________. They convert solar energy to chemical energy and synthesize new organic compounds from CO 2 and H 2 O. 1. Mitochondria and chloroplasts are the main energy transformers of cells Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

31. Mitochondria and chloroplasts are not part of the endomembrane system. Both organelles have small quantities of _______, separate from the nucleus Mitochondria and chloroplasts grow and reproduce as ________________ organelles. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

32. Almost all eukaryotic cells have mitochondria. There may be one very large mitochondrion or hundreds to thousands of individual mitochondria. The number of mitochondria is __________ with aerobic metabolic activity. Mitochondria have a smooth outer membrane and a highly folded inner membrane, the ________. The inner membrane encloses the ______________________, a fluid-filled space with DNA, ribosomes, and enzymes. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

33. Fig. 7.17

34. The chloroplast produces sugar via photosynthesis. Chloroplasts gain their color from high levels of the green pigment ___________. Chloroplasts are found in leaves and other green structures of plants and in eukaryotic algae. The processes in the chloroplast are separated from the cytosol by ______________. Inside the innermost membrane is a fluid-filled space, the _______, in which float membranous sacs, the ____________. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

35. Fig. 7.18

36. CHAPTER 7 A TOUR OF THE CELL Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section G: Cell Walls 1.Plant cells are encased by cell walls

37. The __________, found in prokaryotes, fungi, and some protists, has multiple functions. In plants, the cell wall protects the cell, maintains its shape, and prevents excessive uptake of water. It also supports the plant against the force of gravity. The thickness and chemical composition of cell walls differs from species to species and among cell types. Plants- _______ Fungi-________ Bacteria- lipopolysachharide and _________________ 1. Plant cells are encased by cell walls Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings