Review Prokaryotes vs Eukaryotes Slide 1 of 49

Review: Prokaryotes vs. Eukaryotes Slide 1 of 49 Copyright Pearson Prentice Hall End Show

Slide 2 of 49 Copyright Pearson Prentice Hall End Show

8 -2 Cell Structure Slide 3 of 49 Copyright Pearson Prentice Hall End Show

What are the functions of the major cell structures? Slide 4 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Eukaryotic Cell Structures within a eukaryotic cell that perform important cellular functions are known as organelles. Cell biologists divide the eukaryotic cell into two major parts: the nucleus and the cytoplasm. The Cytoplasm is the portion of the cell outside the nucleus. Slide 5 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Eukaryotic Cell Structures Plant Cell Nucleolus Nucleus Smooth endoplasmic reticulum Nuclear envelope Ribosome (free) Rough endoplasmic reticulum Ribosome (attached) Golgi apparatus Cell wall Cell membrane Chloroplast Mitochondrion Vacuole Slide 6 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Eukaryotic Cell Structures Animal Cell Nucleolus Nucleus Smooth endoplasmic reticulum Ribosome (free) Nuclear envelope Cell membrane Rough endoplasmic reticulum Ribosome (attached) Centrioles Golgi apparatus Mitochondrion Slide 7 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Nucleus What is the function of the nucleus? Slide 8 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Nucleus The nucleus is the control center of the cell. The nucleus contains nearly all the cell's DNA and with it the coded instructions for making proteins and other important molecules. Slide 9 of 49 Copyright Pearson Prentice Hall End Show

Nucleus • Is surrounded by a nuclear envelope composed of two membranes, which are dotted with thousands of nuclear pores that allow material to move into and out of the nucleus. • Chromatin is the granular material you can see inside the nucleus, which is DNA bound to protein. • When the cell divides chromatin condenses to form chromosomes. • Nucleolus is a small, dense region where the assembly of ribosomes begins. Slide 10 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Nucleus The Nucleus Chromatin Nuclear envelope Nucleolus Nuclear pores Slide 11 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Ribosomes What is the function of the ribosomes? Slide 12 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Ribosomes One of the most important jobs carried out in the cell is making proteins. Proteins are assembled on ribosomes. Ribosomes are small particles of RNA and protein found throughout the cytoplasm. Slide 13 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Endoplasmic Reticulum What is the function of the endoplasmic reticulum? Slide 14 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Endoplasmic Reticulum There are two types of ER—rough and smooth. Endoplasmic Reticulum Ribosomes Slide 15 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Endoplasmic Reticulum • The endoplasmic reticulum… – Is the site were lipid components of the cell membrane are assembled, along with proteins and other materials that are exported from the cell. • Rough ER – involved in the synthesis of proteins. Called rough because it has ribosomes on the surface which insert newly made proteins into the rough ER. • Smooth ER – does not have ribosomes and contains collections of enzymes that perform specialized tasks, including synthesis of membrane lipids and the detoxification of drugs. Slide 16 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Golgi Apparatus What is the function of the Golgi apparatus? Slide 17 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Golgi Apparatus The Golgi apparatus appears as a stack of closely apposed membranes. The function is to modify, sort, and package proteins and other materials from the ER for storage in the cell or secretion outside the cell. Slide 18 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Golgi Apparatus What is the function of lysosomes? • Lysosomes are small organelles filled with enzymes. • Lysosomes digest, or breakdown, lipids, carbohydrates, and proteins into small molecules that can be used by the rest of the cell. • They also are involved in breaking down organelles that have outlived their usefulness. Copyright Pearson Prentice Hall Slide 19 of 49 End Show

7 -2 Eukaryotic 8. 2 Cell Structure Vacuoles What is the function of vacuoles? Slide 20 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Vacuoles • Saclike structures that store materials such as water, salts, proteins and carbohydrates in some cells. • In many plant cells there is a single, large central vacuole filled with liquid that helps support the plant’s structure. Copyright Pearson Prentice Hall Vacuole Slide 21 of 49 End Show

7 -2 Eukaryotic 8. 2 Cell Structure Vacuoles are also found in some unicellular organisms and in some animals. Vacuoles Contractile vacuole The paramecium contains a contractile vacuole that pumps excess water out of the cell. Slide 22 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Mitochondria and Chloroplasts What is the function of the mitochondria? Slide 23 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Mitochondria and Chloroplasts Mitochondria Nearly all eukaryotic cells contain mitochondria. Mitochondria convert the chemical energy stored in food into compounds that are more convenient for the cell to use. Mitochondrion Slide 24 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Mitochondria and Chloroplasts What is the function of chloroplasts? Slide 25 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Chloroplasts Mitochondria and Chloroplasts Chloroplast Plants and some other organisms contain chloroplasts. Chloroplasts capture energy from sunlight and convert it into chemical energy in a process called photosynthesis. Slide 26 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Cytoskeleton What are the functions of the cytoskeleton? Slide 27 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Cytoskeleton The cytoskeleton is a network of protein filaments that helps the cell to maintain its shape. The cytoskeleton is also involved in movement. The cytoskeleton is made up of: • microfilaments • microtubules Slide 28 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic 8. 2 Cell Structure Cytoskeleton Cell membrane Endoplasmic reticulum Microtubule Microfilament Ribosomes Mitochondrion Copyright Pearson Prentice Hall Slide 29 of 49 End Show

7 -2 Eukaryotic 8. 2 Cell Structure Cytoskeleton Centrioles are located near the nucleus and help to organize cell division. Slide 30 of 49 Copyright Pearson Prentice Hall End Show

7 -2 Eukaryotic Cell Structure Cellular Boundaries • The cell membrane regulates what enters and leaves the cell and also protects and supports the cell. • The membrane only allows certain things to cross it. Scientists call this semipermeable or selectively permeable. • The cell wall is a strong supporting layer around the cell membrane in plants and most prokaryotes. Slide 31 of 49 End Show

7 -2 Eukaryotic Cell Structure Cell Membranes Cell membrane is made of a phospholipid bilayer. Slide 32 of 49 End Show