Chapter 4 Table of Contents Section 1 The History of Cell Biology Cell Structure and Function Table of Contents Section 1 The History of Cell Biology Section 2 Introduction to Cells Section 3 Cell Organelles and Features Section 4 Unique Features of Plant Cells

Section 1 The History of Cell Biology Chapter 4 Objectives Name the scientists who first observed living and nonliving cells. Summarize the research that led to the development of the cell theory. State the three principles of the cell theory. Explain why the cell is considered to be the basic unit of life.

Introduction to the Cell Definition – A cell is the smallest unit of structure and function of living things that carries on life processes.

A. Discovery of the Cell Robert Hooke ( 1665) – 1st to see cells; looked at cork (dead plant cell); box-shaped structures looked like monk’s rooms called ‘cells’.

A. Discovery of the Cell Anton Van Leeuwenhoek (1673) – 1st to see living cells. Scraped mouth: bacteria, yeast. Water: Protozoans, “Animalcules”.

A. Discovery of the Cell Matthias Schleiden (1838) – Botanist, concluded all plants are made of cells.

A. Discovery of the Cell Theodor Schwann (1839) – Zoologist, concluded all animals are made of cells

A. Discovery of the Cell Rudolf Virchow (1855) – Physician, concluded cells come only from other living cells.

Section 1 The History of Cell Biology Chapter 4 Cell Theory

A. Discovery of the Cell This information gave evidence for the Cell Theory: Cells are the basic unit of structure and function in all living things. All living things are made of cells. Cells come only from the reproduction of other living cells.

The Cell Theory, continued Section 1 The History of Cell Biology Chapter 4 The Cell Theory, continued Think & Discuss: Cellular Basis of Life All living things are made of organized parts, obtain energy from their surroundings, perform chemical reactions, change with time, respond to their environment, and reproduce.

Section 2 Introduction to Cells Chapter 4 Objectives Explain the relationship between cell shape and cell function. Identify the factor that limits cell size. Describe the three basic parts of a cell. Compare prokaryotic cells and eukaryotic cells. Analyze the relationship among cells, tissues, organs, organ systems, and organisms.

B. Cell Diversity Cell Size Most cells are only visible with microscope. Cell size varies from 2 m to .2m (.2 x 10-6) Examples: Bacteria - 0.2 m (.000008 in. or 8 millioneth in.) Giraffe leg nerve – 2 m (6 ½ ft.) Eggs Most body and plant cells – 10 to 50 m (.002 in.)

Think & Discuss: Chapter 4 Cell Size Section 2 Introduction to Cells Chapter 4 Think & Discuss: Cell Size Cell size is limited by a cell’s surface area–to-volume ratio.

B. Cell Diversity Why are Cells so Small? Diffusion is too slow to move nutrients & wastes through cell. As cell size increases, volume increases at faster rate than surface area. Surface area becomes too small to allow materials to enter cell quickly enough to meet its needs.

B. Cell Diversity Cell Shape The shape of a cell helps it to perform its function. Examples: a. RBCs – concave, flexible – squeeze thru vessels b. WBCs – change shape – engulf particles c. Nerves – long, threadlike, branched – receive & send messages d. Epithelial tissue – flat, packed – protection e. Muscles – long, rod-like, contract – pull parts together

Chapter 4 Cell Diversity Cell Shape Section 2 Introduction to Cells Chapter 4 Cell Diversity Cell Shape A cell’s shape reflects its function.

Cellular Organization Section 2 Introduction to Cells Chapter 4 Cellular Organization Think & Discuss: In multicellular eukaryotes, cells organize into tissues, organs, organ systems, and finally organisms.

How are organelles like organs? Organelles perform specific functions to keep a cell healthy and alive. Organs perform specific functions to keep an organism healthy and alive.

Think & Discuss: Chapter 4 Two Basic Types of Cells Prokaryotes Section 2 Introduction to Cells Chapter 4 Two Basic Types of Cells Think & Discuss: Prokaryotes Prokaryote cells lack a nucleus and membrane-bound organelles.

B. Cell Diversity Eukaryotes – cells that have a nucleus and membrane-bound organelles. Prokaryotes – cells that lack a nucleus and have no membrane-bound organelles. (bacteria)

Comparing Prokaryotes and Eukaryotes Section 2 Introduction to Cells Chapter 4 Comparing Prokaryotes and Eukaryotes

Think & Discuss: Chapter 4 Basic Parts of a Cell Section 2 Introduction to Cells Chapter 4 Basic Parts of a Cell Think & Discuss: The three basic parts of a cell are the plasma membrane, the cytoplasm, and the nucleus.

B. Cell Diversity Internal Organization a. Organelles – cell components that perform specific functions to maintain the life of the cell. b. Cell Membrane – Thin membrane surrounding cell. c. Nucleus – large organelle near center of cell; contains genetic information; directs cell activities.

Chapter 4 Objectives Section 3 Cell Organelles and Features Describe the structure and function of a cell’s plasma membrane. Summarize the role of the nucleus. List the major organelles found in the cytosol, and describe their roles. Identify the characteristics of mitochondria. Describe the structure and function of the cytoskeleton.

Internal Organization of a Cell Section 2 Introduction to Cells Chapter 4 Internal Organization of a Cell

Basic Parts of a Cell, continued Section 2 Introduction to Cells Chapter 4 Basic Parts of a Cell, continued Cytoplasm - (Cytosol) a. Located between cell membrane & nucleus b. Contains gel-like fluid called Cytosol and organelles. c. Helps give shape to cell.

B. Organelles: a. Organelles – cell components that perform specific functions to maintain the life of the cell.

Endoplasmic Reticulum (“E.R.”) Section 3 Cell Organelles and Features Chapter 4 Endoplasmic Reticulum (“E.R.”) a. Intracellular “Highway” b. Membranous tubes used to transport molecules c. Rough ER – has ribosomes; transports proteins d. Smooth ER – no ribosomes; makes lipids

Endoplasmic Reticulum, continued Section 3 Cell Organelles and Features Chapter 4 Endoplasmic Reticulum, continued The smooth ER builds lipids and participates in detoxification of toxins.

Endoplasmic Reticulum (ER) and Ribosomes Section 3 Cell Organelles and Features Chapter 4 Endoplasmic Reticulum (ER) and Ribosomes

Chapter 4 Ribosomes Ribosomes a. site of protein synthesis Section 3 Cell Organelles and Features Chapter 4 Ribosomes Ribosomes a. site of protein synthesis b. Located on rough E.R. and scattered throughout cytoplasm

Section 3 Cell Organelles and Features Chapter 4 Ribosomes

Golgi Apparatus (“Packing & Shipping”) Section 3 Cell Organelles and Features Chapter 4 Golgi Apparatus (“Packing & Shipping”) a. Stack of flat membranous sacs. b. Packages proteins from the ER c. Secretes (‘ships’) them to other parts

Chapter 4 Mitochondria Mitochondria (“Powerhouse”) Section 3 Cell Organelles and Features Chapter 4 Mitochondria Mitochondria (“Powerhouse”) a. site of cellular respiration- make ATP energy from glucose b. inner membrane has many folds (Cristae) to increase surface area c. large numbers found in muscle cells

Section 3 Cell Organelles and Features Chapter 4 Mitochondria Mitochondria harvest energy from organic compounds and transfer it to ATP.

Section 3 Cell Organelles and Features Chapter 4 Mitochondrion

Section 3 Cell Organelles and Features Chapter 4 Vesicles (Vesicles, including lysosomes (digestive enzymes) and peroxisomes (detoxification enzymes), are classified by their contents.) Lysosomes (“Cleaning Crew”) a. Sac of digestive enzymes b. Break down nutrients, invaders, debris

Processing of Proteins Section 3 Cell Organelles and Features Chapter 4 Processing of Proteins

Section 3 Cell Organelles and Features Chapter 4 Cytoskeleton (The cytoskeleton is made of protein fibers that help cells move and maintain their shape.) Cytoskeleton a. Microfilaments – fine protein threads Ex: Actin – cause muscles to contract b. Microtubules – hollow protein tubes Ex: Spindle Fibers – move chromosomes

Section 3 Cell Organelles and Features Chapter 4 Cytoskeleton

Think & Discuss: Chapter 4 Cytoskeleton, continued Cilia and Flagella Section 3 Cell Organelles and Features Chapter 4 Cytoskeleton, continued Think & Discuss: Cilia and Flagella (Cilia and flagella are hairlike structures that extend from the surface of the cell, where they assist in movement.)

Cytoskeleton, continued Section 3 Cell Organelles and Features Chapter 4 Cytoskeleton, continued Cilia a. Tiny hair-like projections on cell membrane packed in rows b. Wave, move mucus, catch debris Flagella a. Long, whip-like, on cell surface b. Allow sperm cells to swim

Structure of Cilia and Flagella Section 3 Cell Organelles and Features Chapter 4 Structure of Cilia and Flagella

Cytoskeleton, continued Section 3 Cell Organelles and Features Chapter 4 Cytoskeleton, continued Centrioles A. two short cylinders of microtubules at right angles to each other B. involved in cell division.

Chapter 4 Nucleus Nucleus Section 3 Cell Organelles and Features Chapter 4 Nucleus Nucleus a. Contains DNA (genetic info) – directs cell’s activities b. Located near center of cell c. Nuclear Envelope – porous, double membrane d. Nucleolus – produces ribosomes e. Chromatin – “thread-like” DNA

Section 3 Cell Organelles and Features Chapter 4 Nucleus of a Cell

Parts of the Eukaryotic Cell A. Cell Membrane Next, we’ll discuss: Section 2 Introduction to Cells Chapter 4 Parts of the Eukaryotic Cell A. Cell Membrane Next, we’ll discuss: Plasma Membrane (The cell’s outer boundary, called the plasma membrane (or the cell membrane), covers a cell’s surface and acts as a barrier between the inside and the outside of a cell. )

Think & Discuss: Chapter 4 Plasma Membrane, continued Section 3 Cell Organelles and Features Chapter 4 Plasma Membrane, continued Think & Discuss: Membrane Proteins Cell membranes often contain proteins embedded within the phospholipid bilayer.

Parts of the Eukaryotic Cell A. Cell Membrane Section 2 Introduction to Cells Chapter 4 Parts of the Eukaryotic Cell A. Cell Membrane Selectively Permeable – controls which substances pass into and out of cell.

Parts of the Eukaryotic Cell A. Cell Membrane Section 2 Introduction to Cells Chapter 4 Parts of the Eukaryotic Cell A. Cell Membrane 1. Membrane Lipids – lipids (fats) allow fat-soluble substances to pass through 2. Phospholipids form a lipid bilayer.

Structure of Lipid Bilayer Section 3 Cell Organelles and Features Chapter 3 Structure of Lipid Bilayer

Section 3 Cell Organelles and Features Chapter 4 Cell Membrane

Parts of the Eukaryotic Cell A. Cell Membrane Section 2 Introduction to Cells Chapter 4 Parts of the Eukaryotic Cell A. Cell Membrane Membrane Proteins – allow fat-nonsolubles to pass through Fluid Mosaic Model – lipid bilayer behaves more like a fluid than a solid. Lipids and proteins can move (fluid) within bilayer, so their pattern (mosaic) changes.

Chapter 4 Basic Parts of a Cell Do You Remember? Section 2 Introduction to Cells Chapter 4 Basic Parts of a Cell Do You Remember? The three basic parts of a cell are: The plasma membrane, cytoplasm, and nucleus.

The Two Basic Types of Cells? Section 2 Introduction to Cells Chapter 4 Do you Remember: The Two Basic Types of Cells? Prokaryotes Prokaryote cells lack a nucleus and membrane-bound organelles. (Bacteria)

Eukaryotes – cells that have a nucleus and membrane-bound organelles Eukaryotes – cells that have a nucleus and membrane-bound organelles. (Animals, Plants, Fungus, Protist)

Chapter 4 Objectives Section 4 Unique Features of Plant Cells List three structures that are present in plant cells but not in animal cells. Compare the plasma membrane,the primary cell wall, and the secondary cell wall. Explain the role of the central vacuole. Describe the roles of plastids in the life of a plant. Identify features that distinguish prokaryotes, eukaryotes, plant cells, and animal cells.

Section 4 Unique Features of Plant Cells Chapter 4 Plant Cells Plant cells have cell walls, central vacuoles, and plastids.

Section 4 Unique Features of Plant Cells Chapter 4 A. Cell Wall A solid, rigid, outer covering; provides support and protection.

Chapter 4 Parts of a Cell Wall Section 4 Unique Features of Plant Cells Chapter 4 Parts of a Cell Wall

Chapter 4 B. Central Vacuole Section 4 Unique Features of Plant Cells Chapter 4 B. Central Vacuole Storage areas- store water, enzymes, and waste products and provide support for plant tissue. Large – up to 90% of cell’s volume

Chapter 4 C. Plastids 1. Store starch, fats, or pigments Section 4 Unique Features of Plant Cells Chapter 4 C. Plastids 1. Store starch, fats, or pigments 2. Chloroplast – contains chlorophyll for photosynthesis 3. Leucoplast – stores starch Chromoplast – makes & stores pigments: Carotene – orange; Xanthrophyll – yellow

Section 4 Unique Features of Plant Cells Chapter 4 Chloroplasts

Chapter 4 Comparing Cells Section 4 Unique Features of Plant Cells Chapter 4 Comparing Cells Prokaryotes, animal cells, and plant cells can be distinguished from each other by their unique features.

Comparing Plant and Animal Cells Section 4 Unique Features of Plant Cells Chapter 4 Comparing Plant and Animal Cells

Chapter 4 Multiple Choice Standardized Test Prep Multiple Choice 1. The eukaryotic nucleus houses all of the following except the A. RNA B. DNA C. nucleolus D. endoplasmic reticulum

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued 1. The eukaryotic nucleus houses all of the following except the A. RNA B. DNA C. nucleolus D. endoplasmic reticulum

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued 2. Which structure contributes to support and movement within a cell? F. crista G. cell wall H. ribosome J. microfilament

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued 2. Which structure contributes to support and movement within a cell? F. crista G. cell wall H. ribosome J. microfilament

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued 3. Which of the following statements about RNA is true? A. RNA is found only in proteins. B. RNA is found only in the nucleus. C. RNA is found only in the cytoplasm. D. RNA is found in the nucleus and cytoplasm.

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued 3. Which of the following statements about RNA is true? A. RNA is found only in proteins. B. RNA is found only in the nucleus. C. RNA is found only in the cytoplasm. D. RNA is found in the nucleus and cytoplasm.

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued The graph below shows the relationship between cell size and surface area–to–volume ratio. Use the graph below to answer the questions that follow. 4. By what percentage does the surface area–to – volume ratio change when a cell grows from 1 to 2 µm in diameter? F. 10 percent G. 20 percent H. 50 percent J. 90 percent

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued The graph below shows the relationship between cell size and surface area–to–volume ratio. Use the graph below to answer the questions that follow. 4. By what percentage does the surface area–to – volume ratio change when a cell grows from 1 to 2 µm in diameter? F. 10 percent G. 20 percent H. 50 percent J. 90 percent

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued The graph below shows the relationship between cell size and surface area–to–volume ratio. Use the graph below to answer the questions that follow. 5. What is the maximum diameter that this cell could attain before the surface area–to-volume ratio would fall below 1? A. 2 µm B. 5 µm C. 10 µm D. 15 µm

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued The graph below shows the relationship between cell size and surface area–to–volume ratio. Use the graph below to answer the questions that follow. 5. What is the maximum diameter that this cell could attain before the surface area–to-volume ratio would fall below 1? A. 2 µm B. 5 µm C. 10 µm D. 15 µm

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued 6. mitochondria : energy release :: ribosome : F. cell support G. protein synthesis H. cellular digestion J. cellular transport

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued 6. mitochondria : energy release :: ribosome : F. cell support G. protein synthesis H. cellular digestion J. cellular transport

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued The figure below shows a diagram of a cell. Use the figure to answer the question that follows. 7. What is the function of the structure labeled 1? A. to make ATP B. to make proteins C. to make carbohydrates D. to move proteins through the cell

Multiple Choice, continued Chapter 4 Standardized Test Prep Multiple Choice, continued The figure below shows a diagram of a cell. Use the figure to answer the question that follows. 7. What is the function of the structure labeled 1? A. to make ATP B. to make proteins C. to make carbohydrates D. to move proteins through the cell

Chapter 4 Short Response Standardized Test Prep Short Response A cell’s shape is generally related to its function. Skin cells are flat and platelike. Nerve cells have long extensions. Explain the relationship between the shape of skin and nerve cells and their function in the body.

Short Response, continued Chapter 4 Standardized Test Prep Short Response, continued Answer: Cell shape reflects the different functions of cells. For example, the long extensions of nerve cells allow these cells to receive and transmit nerve impulses in many directions. Also, the flat shape of skin cells suits their function of covering and protecting the surface of the body.

Chapter 4 Extended Response Standardized Test Prep Extended Response Despite the diversity among cells, eukaryotic cells share many common features. Part A Describe the structure and function of the organelles found in an animal cell. Part B Summarize the differences that distinguish animal cells from bacteria and plant cells.

Extended Response, continued Chapter 4 Standardized Test Prep Extended Response, continued Answer: Part A Answers may include the following: The nucleus holds and protects DNA; Mitochondria transfer energy to ATP; Ribosomes manufacture proteins; The ER functions as an intracellular highway; The Golgi apparatus directs proteins to other parts of the cell; Vesicles digest materials, break down old cells, and play a role in protein synthesis. Part B Plant and bacterial cells, unlike animal cells, have a cell wall. Bacterial cells, unlike plant and animal cells, lack a membrane-bound nucleus and organelles. Some bacterial cells and all plant cells have plastids.