Workbook Cells and Tissues

The basic unit of structure and function in the human body is the cell. Each of a cell’s parts, or organelles, as well as the entire cell, is organized to perform a specific function. Cells have the ability to metabolize, grow and reproduce, move, and respond to stimuli. The cells of the body differ in shape, size, and in specific roles in the body. Cells that are similar in structure and function form tissues, which, in turn, construct the various body organs. Student activities in this chapter include questions relating to the structure and function of the generalized animal cell and to the general arrangement of tissues and their contribution to the activities of the various body organs. CELLS Overview 1. Answer the following questions by inserting your responses in the answer blanks. _________________________ 1. Carbon Nitrogen _________________________ 2. _________________________ 3. Oxygen Hydrogen _________________________ 4. water _________________________ 5. _________________________ 6. Calcium _________________________ 7. Iron Reproduction _________________________ 8. 1–4. Name the four elements that make up the bulk of living matter. 5. Name the single most abundant molecule in living matter. 6. Name the trace element most important for making bones hard. 7. Name the element, found in small amounts in the body, that is needed to make hemoglobin for oxygen transport. 8–12. Although there are many specific “jobs” that certain cells are able to do, name five functions common to all cells. _________________________ 9. Metabolism Responsiveness 11. _________________________ _________________________ 10. Excretion _________________________ 12. Growth 33 34 Squamous _________________________ 13. Cuboidal _________________________ 14. Columnar _________________________ 15. Extracellular Fluid _________________________ 16. Epithelial Cell _________________________ 17. 13–15. List three different cell shapes. 16. Name the fluid, similar to seawater, that surrounds and bathes all body cells. 17. Name the flattened cells, important in protection against damage, that fit together like tiles. (This is just one example of the generalization that a cell’s structure is very closely related to its function in the body.) Anatomy of a Generalized Cell 2. Using the list of terms on the following page, correctly label all cell parts indicated by leader lines in Figure 3–1. Then, select different colors for each structure and use them to color the coding circles and the corresponding structures in the illustration. mitochondria .smooth Er Nuclear membrane Cytosol Golgi Apparatus Vacuole Nucleolus Chromatin Threads Centrioles Rough Er Plasma membrane Microvilli Figure 3–1 Chapter 3 Cells and Tissues ○ Plasma membrane ○ Mitochondrion ○ Centriole(s) ○ Nuclear membrane ○ Chromatin thread(s) ○ Nucleolus ○ Golgi apparatus ○ Rough endoplasmic reticulum (Rough ER) ○ Microvilli ○ Smooth endoplasmic reticulum (Smooth ER) 35 3. Figure 3–2 is a diagram of a portion of a plasma membrane. Select four different colors and color the coding circles and the corresponding structures in the diagram. Then, respond to the questions that follow, referring to Figure 3–2, and insert your answers in the answer blanks. ○ Phospholipid molecules ○ Carbohydrate molecules ○ Protein molecules ○ Cholesterol molecules Cell exterior A B C Cell interior Figure 3–2 Glycocalyx 1. Name the carbohydrate-rich area at the cell surface (indicated by bracket A). _______________ 2. Which label, B or C, indicates the nonpolar region of a phospholipid molecule? ____________ C Hydrophobic 3. Does nonpolar mean hydrophobic or hydrophilic? _________________________________________ Transport 4. What are two roles of the membrane proteins? _____________________________________________ Communication and _____________________________________________ 36 4. Based on Figure 3–3, answer the following: (A) Label the specializations of the plasma membrane. (B) Color the coding circles and the corresponding cell parts. (C) Answer the questions provided below. ○ Nucleus ○ Nucleolus ○ Mitochondrion ○ ER A Microvilli B Tight Junctions C Desmosomes Figure 3–3 1. What type of cell function(s) does the presence of microvilli typically Absorption indicate? __________________________________________________________________________________ Tight junction 2. Which cell junction forms an impermeable barrier? _________________________________________ Desmosome 3. Which cell junction is an anchoring junction? _______________________________________________ Desmosome 4. Which junction has linker proteins spanning the intercellular space? ________________________ Tight junction 5. Which cell junction is not illustrated, and what is its function? ______________________________ Helps prevent molecules from passing though the extracellular space of adjacent cells and ______________________________________________________________________________________________ restricts the movement of membrane proteins 6. Which two types of membrane junctions would you expect to find between cells of the heart? Desmosome Gap Junction _______________________________________________ and ____________________________________________ Chapter 3 Cells and Tissues 37 5. Relative to cellular organelles, circle the term or phrase that does not belong in each of the following groupings. Then, fill in the answer blanks with the correct group name. Enzyme 1. Peroxisomes Enzymatic breakdown Centrioles 2. Microtubules Intermediate filaments Microfilaments 3. Ribosomes Smooth ER 4. Double membrane 5. Centrioles 6. ER 7. Nuclear pores Rough ER Cristae Mitochondria Ribosomes DNA Amino acids ATP production Cilia Lysosomes Cilia Group: breakdown _________ Cytoskeleton Group: _________ Group: _________ Er Vitamin A storage Mitochondria Group: ,_________ Group:Microtubules _________ Flagella Transport vesicles Lysosomes Golgi apparatus Chromatin Nucleolus RER Group: ________ Group: _________ Nucleus 6. Name the cytoskeletal element (microtubules, microfilaments, or intermediate filaments) described by each of the following phrases. Microtubules _________________________ 1. Give the cell its shape _________________________ Intermediate filaments 2. Resist tension placed on a cell microtubules. _________________________ 3. Radiate from the cell center Microtubules _________________________ 4. Involved in moving intracellular structures Intermediate filaments 5. Are the most stable _________________________ Microtubules _________________________ 6. Have the thickest diameter 7. Different organelles are abundant in different cell types. Match the cell types with their abundant organelles by selecting a letter or letters from the key choices. Items may have more than one answer. Key Choices A. Golgi apparatus B. Intermediate filaments C. Lysosomes D. Microfilaments E. Mitochondria F. Peroxisomes .H 1. Cell lining the small intestine (assembles fats) ______ C 2. White blood cell; a phagocyte ______ ______ F 3. Liver cell that detoxifies carcinogens ______ D 4. Muscle cell (contractile cell) A G 5. Mucus-secreting cell (secretes a protein product) ______ ______ B 6. Cell at external skin surface (withstands friction and tension) E 7. Kidney tubule cell (makes and uses large amounts of ATP) ______ G. Rough ER H. Smooth ER 38 Cell Physiology Membrane Transport 8. Figure 3–4 shows a semipermeable sac, containing 4% NaCl, 9% glucose, and 10% albumin, suspended in a solution with the following composition: 10% NaCl, 10% glucose, and 40% albumin. Assume the sac is permeable to all substances except albumin. Using the key choices, insert the letter indicating the correct event in the answer blanks. Key Choices A. Moves into the sac B. Moves out of the sac C. Does not move A _________________________ 1. Glucose C _________________________ 3. Albumin B _________________________ 2. Water A _________________________ 4. NaCl Solution contains: 10% NaCl 10% Glucose 40% Albumin Sac contains: 4% NaCl 9% Glucose 10% Albumin Figure 3–4 9. Figure 3–5 shows three microscopic fields (A–C) containing red blood cells. Arrows indicate the direction of net osmosis. Respond to the following questions, referring to Figure 3–5, by inserting your responses in the spaces provided. A 1. Which microscopic field contains a hypertonic solution? ___________________________________ The cells in this field are said to be ________________________________________________________ crenated B 2. Which microscopic field contains an isotonic bathing solution? _____________________________ Solutions that have the same concentration of What does isotonic mean? _________________________________________________________________ non-penetrating solutes as the Cells ___________________________________________________________________________________________ C 3. Which microscopic field contains a hypotonic solution? ____________________________________ The cells have lysed from What is happening to the cells in this field and why? ______________________________________ taking up too much water Chapter 3 Cells and Tissues A B 39 C Figure 3–5 10. Figure 3–6 is a simplified diagram of the plasma membrane. Structure A represents channel proteins constructing a pore, structure B represents an ATP-energized solute pump, and structure C is a transport protein that does not depend on energy from ATP. (A) Identify these structures and the membrane phospholipids by color. ○ Channel ○ Solute pump ○ Passive transport protein carrier Amino acid Cell exterior Cell interior Steroid Fat K+ Cl– CO2 K+ Glucose Figure 3–6 (B) For each substance that moves through the plasma membrane, draw an arrow indicating its (most likely) direction of movement (into or out of the cell). If it is moved actively, use a red arrow; if it is moved passively, use a blue arrow. Color the coding arrows. Active Passive Glucose CO2 Na+ O2 Phospholipids O2 Na+ H 2O ○ Amino acid 40 (C) Answer the following questions referring to Figure 3–6: 1. Which of the substances shown moves passively through the lipid part Fat, steroid of the membrane? ______________________________________________________________________ 2. Which of the substances shown enters the cell by attachment to a passive Glucose transport protein carrier? _______________________________________________________________ 3. Which of the substances shown moves passively through the membrane Water by moving through its pores? __________________________________________________________ 4. Which of the substances shown would have to use a solute pump to be NA, K, Amino acid transported through the membrane? ___________________________________________________ 11. Select the key choices that characterize each of the following statements. Insert the appropriate letter(s) or corresponding term(s) in the answer blanks. Items may have more than one answer. Key Choices A. Active transport B. Diffusion, simple C. Diffusion, osmosis D. Exocytosis E. Facilitated diffusion F. Filtration G. Phagocytosis H. Pinocytosis I. Receptor-mediated endocytosis _________________________ 1. Engulfment processes that require ATP . GHI _________________________ 2. Driven by concentration gradient ADGHI F 3. Driven by hydrostatic (fluid) pressure (typically blood pressure _________________________ in the body) _________________________ 4. Moves down a concentration gradient BCE AGHI _________________________ 5. Moves up (against) a concentration gradient; requires a carrier _________________________ 6. Moves small or lipid-soluble solutes through the membrane B _________________________ 7. Transports amino acids and Na+ through the plasma membrane E DHIG 8. Examples of vesicular transport _________________________ GI _________________________ 9. A means of bringing fairly large particles into the cell D _________________________ 10. Used to eject wastes and to secrete cell products E _________________________ 11. Membrane transport using channels or carrier proteins that does not require ATP Chapter 3 Cells and Tissues 41 Cell Division 12. The following statements provide an overview of the structure of DNA (genetic material) and its role in the body. Choose responses from the key choices that complete the statements. Insert the appropriate answers in the answer blanks. Key Choices A. B. C. D. E. F. Adenine Amino acids Bases Codons Complementary Cytosine G. H. I. J. K. L. P _________________________ 1. K _________________________ 2. T _________________________ 3. O _________________________ 4. C _________________________ 5. _________________________ 6. B E _________________________ 7. F _________________________ 8. V _________________________ 9. S _________________________ 10. Q _________________________ 11. E _________________________ 12. M _________________________ 13. L _________________________ 14. _________________________ 15. N _________________________ 16. H I _________________________ 17. _________________________ 18. R Enzymes Genes Growth Guanine Helix New M. N. O. P. Q. R. Nucleotides Old Phosphate Proteins Replication Repair S. T. U. V. W. X. Ribosome Sugar (deoxyribose) Template, or model Thymine Transcription Uracil DNA molecules contain information for building specific (1) . In a three-dimensional view, a DNA molecule looks like a spiral staircase; this is correctly called a (2) . The constant parts of DNA molecules are the (3) and (4) molecules, forming the DNA-ladder uprights, or backbones. The information of DNA is actually coded in the sequence of nitrogen-containing (5) , which are bound together to form the “rungs” of the DNA ladder. When the four DNA bases are combined in different three-base sequences, called triplets, different (6) of the protein are called for. It is said that the N-containing bases of DNA are (7) , which means that only certain bases can fit or interact together. Specifically, this means that (8) can bind with guanine, and adenine binds with (9) . The production of proteins involves the cooperation of DNA and RNA. RNA is another type of nucleic acid that serves as a “molecular slave” to DNA. That is, it leaves the nucleus and carries out the instructions of the DNA for the building of a protein on a cytoplasmic structure called a (10) . When a cell is preparing to divide, in order for its daughter cells to have all its information, it must oversee the (11) of its DNA so that a “double dose” of genes is present for a brief period. For DNA synthesis to occur, the DNA must uncoil, and the bonds between the N bases must be broken. Then the two single strands of (12) each act as a (13) for the building of a whole DNA molecule. When completed, each DNA molecule formed is half (14) and half (15) . DNA replicates before a cell divides, ensuring that each daughter cell has a complete set of (16) . Cell division, which then follows, provides new cells so that (17) and (18) can occur. 42 13. Identify the phases of mitosis depicted in Figure 3–7 by inserting the correct name in the blank under the appropriate diagram. Then, select different colors to represent the structures listed below and use them to color in the coding circles and the corresponding structures in the illustration. ○ Nuclear membrane(s), if present ○ Centrioles ○ Nucleoli, if present ○ Spindle fibers ○ Chromosomes A Prophase B C telophase D Figure 3–7 Anaphase Metaphase Chapter 3 Cells and Tissues 14. The following statements describe events that occur during the different phases of mitosis. Identify the phase by choosing the correct response(s) from the key choices and inserting the letter(s) or term(s) in the answer blanks. Items may have more than one answer. Key Choices A. Anaphase B. Metaphase C. Prophase D. Telophase E. None of these C _________________________ 1. Chromatin coils and condenses to form deeply staining bodies. _________________________ 2. Centromeres break, and chromosomes begin migration toward A opposite poles of the cell. _________________________ 3. The nuclear membrane and nucleoli reappear. D _________________________ 4. When chromosomes cease their poleward movement, this D phase begins. B _________________________ 5. Chromosomes align on the equator of the spindle. C _________________________ 6. The nucleoli and nuclear membrane disappear. C _________________________ 7. The spindle forms through the migration of the centrioles. E _________________________ 8. Chromosomal material replicates. C _________________________ 9. Chromosomes first appear to be duplex structures. C _________________________ 10. Chromosomes attach to the spindle fibers. D _________________________ 11. A cleavage furrow forms during this phase. Ab _________________________ 12. The nuclear membrane is absent during the entire phase. E _________________________13. A cell carries out its usual metabolic activities. 15. Using the key choices, complete the crossword puzzle by answering each of the clues provided. Key Choices Anucleate Aster Binucleate Centromeres Centrosomes Coiled Cyt asm Interphase Loose Nucleus Prophase Spindle Across 3. The structure that acts as a scaffolding for chromosomal attachment and Spindle movement is called the _______. 4. If a cell undergoes nuclear division but not cytoplasmic division, the product is a Binucleate _________ cell. 7. Chromosomes attach to the spindle fibers by undivided structures Centromeres called ______. . 43 44 Down 1. Cytokinesis is the division of the.cytoplasm ______. 2. Division of the _____ is referred to as mitosis.Nucleus 5. ______ is the period of cell life when the cell is not involved in division. interphase 6. The major structural difference between chromatin and chromosomes is that the latter are Coiled _____. 1 2 r 3 4 5 6 7 Protein Synthesis 16. Figure 3–8 is a diagram illustrating protein synthesis. (A) Select four different colors, and use them to color the coding circles and the corresponding structures in the diagram. (B) Using the letters of the genetic code, label the nitrogen bases on strand 2 of the DNA double helix, on the mRNA strands, and on the tRNA molecules. (C) Answer the questions that follow referring to Figure 3–8, inserting your answers in the answer blanks. ○ Backbones of the DNA double helix ○ tRNA molecules ○ Backbone of the mRNA strands ○ Amino acid molecules Chapter 3 Cells and Tissues 45 Nuclear membrane Nucleus G A 1 C 2 G A A Ribosome C T T A T A Sa me str a nd Figure 3–8 Transcription 1. Transfer of the genetic message from DNA to mRNA is called _________________________. 2. Assembly of amino acids according to the genetic information carried by mRNA is called Translation _________________________. 3. The set of three nitrogen bases on tRNA that is complementary to an mRNA codon is called Anticodon a _________________________. The complementary three-base sequence on DNA is called a Triplet _________________________. 46 BODY TISSUES 17. The four major tissue types are named in Figure 3–9. For each tissue type, provide its major function(s) on the lines after the tissue name. Then, list the location of each tissue type at the end of each leader line. Nervous tissue: Communication Brain Spinal Cord Nerves Muscle tissue: Movement Skeletal Cardiac Smooth Epithelial tissue: Protection Organ lining Skin Connective tissue: Bone Tendon Fat etc. Figure 3–9 Support and cushion Chapter 3 Cells and Tissues 18. Twelve tissue types are diagrammed in Figure 3–10. (A) Identify each specific tissue type by inserting the correct name in the blank below it on the diagram. (B) Select different colors for the following structures and use them to color the coding circles and corresponding structures in the diagrams, when applicable. A C E ○ Epithelial cells ○ Nerve cells ○ Muscle cells ○ ○ Basement membrane ○ Intercalated discs Matrix (Where found, matrix should be colored differently from the living cells of that tissue type. Be careful; this may not be as easy as it seems!) Simple squamous epithelium Cardiac muscle Bone Simple cuboidal Epithelium B D Dense Fibrous Connective F Figure 3–10, A–F skeletal muscle 47 48 G Nervous Tissue H Hyaline Cartilage I Smooth Muscle J Adipose K Stratified squamous L Areolar connective Figure 3–10, G–L 19. Describe briefly how the particular structure of a neuron relates to its function The length of the axon allows neurons to relay info over in the body. _________________________________________________________________ long distances ______________________________________________________________________________ ______________________________________________________________________________ Chapter 3 Cells and Tissues 49 20. Using the key choices, correctly identify the major tissue types described. Enter the appropriate letter or tissue type term in the answer blanks. Key Choices A. Connective B. Epithelium C. Muscle D. Nervous B _________________________ 1. Forms mucous, serous, and epidermal membranes C _________________________ 2. Allows for organ movements within the body D _________________________ 3. Transmits electrochemical impulses A _________________________ 4. Supports body organs B _________________________ 5. Cells of this tissue may absorb and/or secrete substances .D _________________________ 6. Basis of the major controlling system of the body C _________________________ 7. Cells of this tissue shorten to exert force B _________________________ 8. Forms hormones A _________________________ 9. Packages and protects body organs A _________________________ 10. Characterized by having large amounts of nonliving matrix _________________________ 11. Allows you to smile, grasp, swim, ski, and shoot an arrow .C _________________________ 12. Most widely distributed tissue type in the body A _________________________ 13. Forms the brain and spinal cord D 21. Using the key choices, identify the following specific type(s) of epithelial tissue. Enter the appropriate letter or classification term in the answer blanks. Key Choices A. Pseudostratified columnar (ciliated) B. Simple columnar C. Simple cuboidal D. Simple squamous E. Stratified squamous F. Transitional E _________________________ 1. Lines the esophagus and forms the skin epidermis B _________________________ 2. Forms the lining of the stomach and small intestine E _________________________ 3. Best suited for areas subjected to friction _________________________ 4. Lines much of the respiratory tract A A . _________________________ 5. Propels substances (e.g., mucus) across its surface F _________________________ 6. Found in the bladder lining; peculiar cells that slide over one another _________________________ 7. Forms thin serous membranes; a single layer of flattened cells D 50 22. The three types of muscle tissue exhibit certain similarities and differences. Check (✓) the appropriate spaces in the following table to indicate which muscle types exhibit each characteristic. Characteristic Skeletal Cardiac Smooth 1. Voluntarily controlled 2. Involuntarily controlled 3. Banded appearance 4. Single nucleus in each cell 5. Multinucleate 6. Found attached to bones 7. Allows you to direct your eyeballs 8. Found in the walls of stomach, uterus, and arteries 9. Contains spindle-shaped cells 10. Contains cylindrical cells with branching ends 11. Contains long, nonbranching cylindrical cells 12. Displays intercalated discs 13. Concerned with locomotion of the body as a whole 14. Changes the internal volume of an organ as it contracts 15. Tissue of the circulatory pump 23. Circle the term that does not belong in each of the following groupings. Then, fill in the answer blanks with the correct group name. 1. Collagen 2. Cilia 3. Glands 4. Adipose 5. Blood Cell Flagellum Bones Hyaline Smooth Matrix Microvilli Epidermis Osseous Cardiac Cell product Group: _________ Cell product Elastic fibers Mucosae Nervous Skeletal Group: Movement _________ Epithelial tissue Group: _________ ConnectiveTissue Group: _________ Group: Muscle _________ Tissue Chapter 3 Cells and Tissues 51 24. Using the key choices, identify the following connective tissue types. Insert the appropriate letter or corresponding term in the answer blanks. Key Choices A. Adipose connective tissue B. Areolar connective tissue C. Dense fibrous connective tissue D. Hyaline cartilage E. Osseous tissue F. Reticular connective tissue C _________________________ 1. Provides great strength through parallel bundles of collagenic fibers; found in tendons A _________________________ 2. Acts as a storage depot for fat C _________________________ 3. Composes the majority of the dermis of the skin D _________________________ 4. Forms the bony skeleton B _________________________ 5. Composes the lamina propria and packages organs; includes a gel-like matrix with all categories of fibers and many cell types F _________________________ 6. Forms the embryonic skeleton and the surfaces of bones at the joints; reinforces the trachea A _________________________ 7. Provides insulation for the body F _________________________ 8. Matrix with no specific shape, heavily invaded with fibers; appears glassy and smooth D _________________________ 9. Contains cells arranged concentrically around a nutrient canal; matrix is hard due to calcium salts E _________________________ 10. Forms the stroma or internal “skeleton” of lymph nodes, the spleen, and other lymphoid organs Tissue Repair 25. For each of the following statements about tissue repair that is true, enter T in the answer blank. For each false statement, correct the underlined words by writing the correct words in the answer blank. Inflammation _________________________ 1. The nonspecific response of the body to injury is called regeneration. Clotting Proteins 2. Intact capillaries near an injury dilate, leaking plasma, blood cells, _________________________ and antibodies, which cause the blood to clot. The clot at the surface dries to form a scab. Granulation _________________________ 3. During the first phase of tissue repair, capillary buds invade the clot, forming a delicate pink tissue called endodermal tissue. Regeneration _________________________ 4. When damage is not too severe, the surface epithelium migrates beneath the dry scab and across the surface of the granulation tissue. This repair process is called proliferation. 52 T _________________________ 5. If tissue damage is very severe, tissue repair is more likely to occur by fibrosis, or scarring. Collagen _________________________ 6. During fibrosis, fibroblasts in the granulation tissue lay down keratin fibers, which form a strong, compact, but inflexible mass. T _________________________ 7. The repair of cardiac muscle and nervous tissue occurs mainly by fibrosis. DEVELOPMENTAL ASPECTS OF CELLS AND TISSUES 26. Correctly complete each statement by inserting your responses in the answer blanks. Tissues _________________________ 1. Growth _________________________ 2. Nervous _________________________ 3. muscle _________________________ 4. _________________________ 5. Connective Chemical _________________________ 6. _________________________ 7. Physical DNA _________________________ 8. Connective Tissue changes 9. _________________________ Dehydration of tissues 10. _________________________ DecEndocrine activity 11. _________________________ Division _________________________ 12. Benign _________________________ 13. Malignant _________________________ 14. Benign During embryonic development, cells specialize to form (1) . Mitotic cell division is very important for overall body (2) . All tissues except (3) tissue continue to undergo cell division until the end of adolescence. After this time, (4) tissue also becomes amitotic. When amitotic tissues are damaged, they are replaced by (5) tissue, which does not function in the same way as the original tissue. This is a serious problem when heart cells are damaged. Aging begins almost as soon as we are born. Three explanations of the aging process have been offered. One states that (6) insults, such as the presence of toxic substances in the blood, are important. Another theory states that external (7) factors, such as X-rays, help to cause aging. A third theory suggests that aging is programmed in our (8) . Three examples of aging processes seen in all people are (9) , (10) , and (11) . Neoplasms occur when cells “go wild” and the normal controls of cell (12) are lost. The two types of neoplasms are (13) and (14) . The (15) type tends to stay localized and have a capsule. The (16) type is likely to invade other body tissues and spread to other (distant) parts of the body. To correctly diagnose the type of neoplasm, a microscopic examination of the tissue called a (17) is usually done. Whenever possible, (18) is the treatment of choice for neoplasms. _________________________ 15. Malignant _________________________ 16. Biopsy _________________________ 17. Surgical removal 18. _________________________ Hyperplasia _________________________ 19. _________________________ 20. Atrophy An overgrowth of tissue that is not considered to be a neoplasm is referred to as (19) . Conversely, a decrease in the size of an organ or tissue, resulting from loss of normal stimulation, is called (20) . Chapter 3 Cells and Tissues 53 INCRED IBL E JO U RN EY A Visualization Exercise for the Cell A long, meandering membrane with dark globules clinging to its outer surface now comes into sight. 27. Where necessary, complete statements by inserting the missing words in the answer blanks. Cytoplasm _________________________ 1. _________________________ 2. Nucleus _________________________ 3. Mitochondria ATP _________________________ 4. Ribosomes _________________________ 5. RER _________________________ 6. For your second journey, you will be miniaturized to the size of a small protein molecule and will travel in a microsubmarine specially designed to enable you to pass easily through living membranes. You are injected into the intercellular space between two epithelial cells and are instructed to observe one of these cells firsthand and to identify as many of its structures as possible. You struggle briefly with the controls and then maneuver your microsub into one of these cells. Once inside the cell, you find yourself in a kind of “sea.” This salty fluid that surrounds you is the (1) of the cell. _________________________ 7. Pores Far below looms a large, dark, oval structure, much larger than anything else you can see. You conclude that it is the (2) . As you move downward, you pass a cigar-shaped DNA _________________________ 9. structure with strange-looking folds on its inner surface. Although you have a pretty good idea that it must be a (3) , Nucleoli _________________________ 10. you decide to investigate more thoroughly. After passing through the external membrane of the structure, you are confronted with yet another membrane. Once past this membrane, you are inside the strange-looking structure. You activate the analyzer switch in your microsub for a readout indicating which molecules are in your immediate vicinity. As suspected, there is an abundance of energy-rich (4) molecules. Having satisfied your curiosity, you leave this structure to continue the investigation. _________________________ 8. Chromatin A long, meandering membrane with dark globules clinging to its outer surface now comes into sight. You maneuver closer and sit back to watch the activity. As you watch, amino acids are joined together, and a long, threadlike protein molecule is built. The globules must be (5) , and the membrane, therefore, is the (6) . Once again, you head toward the large dark structure seen and tentatively identified earlier. On approach, you observe that this huge structure has very large openings in its outer wall; these openings must be the (7) . Passing through one of these openings, you discover that from the inside, the color of this structure is a result of dark, coiled, intertwined masses of (8) , which your analyzer confirms contain genetic material, or (9) molecules. Making your way through this tangled mass, you pass a round, dense structure that appears to be full of the same type of globules you saw outside. This round structure is the (10) . All this information confirms your earlier identification of this cellular structure, so now you move to its exterior to continue observations. 54 Golgi App. _________________________ 11. Just ahead, you see what appears to be a mountain of flattened sacs with hundreds of small saclike vesicles at its Lysosome edges. The vesicles seem to be migrating away from this area _________________________ 12. and heading toward the outer edges of the cell. The mountain of sacs must be the (11) . Eventually you come upon a rather Isimple-looking membrane-bound sac. Although it doesn’t look too exciting and has few distinguishing marks, it does not resemble anything else you have seen so far. Deciding to obtain a chemical analysis before entering this sac, you activate the analyzer and on the screen you see “Enzymes — Enzymes — Hydrolases — Hydrolases — Danger — Danger.” There is little doubt that this innocent-appearing structure is actually a (12) . Completing your journey, you count the number of organelles identified so far. Satisfied that you have observed most of them, you request retrieval from the intercellular space. AT THE C L I N I C 28. Johnny lacerated his arm and rushed home to Mom so she could “fix it.” His mother poured hydrogen peroxide over the area, and it bubbled vigorously where it came in contact with the wound. Because you can expect that cells were ruptured in the injured area, what do you think was happening here? Peroxisomes were converting the hydrogen peroxide to water and oxygen 29. The epidermis (epithelium of the cutaneous membrane or skin) is a keratinized stratified squamous epithelium. Explain why that epithelium is much better suited for protecting the body’s external surface than a mucosa consisting of a simple columnar epithelium would be. Because they have multiple layers and are more effective against abrasions due to this 30. Streptomycin (an antibiotic) binds to the small ribosomal subunit of bacteria (but not to the ribosomes of the host cells infected by bacteria). The result is the misreading of bacteria mRNA and the breakup of polysomes (mRNA and two or more ribosomes). What process is being affected, and how does this kill the bacterial cells? It inhibits bacterial protein synthesis without which bacteria die Chapter 3 Cells and Tissues 31. Systemic lupus erythematosus (often simply called lupus) is a condition that primarily affects young women. It is a chronic (persistent) inflammation that affects all or most of the connective tissue proper in the body. Suzy is toldby her doctor that she has lupus, and she asks if it will have widespread or merely localized effects within the body. What would the physician answer? Explain. Since connective tissue is present widely in the body Suzy can expect the effects to be widespread 32. Mrs. Linsey sees her gynecologist because she is unable to become pregnant. The doctor discovers granulation tissue in her vaginal canal and explains that sperm are susceptible to some of the same chemicals as bacteria. What is inhibiting the sperm? Granulation tissue secrete substances that kill bacteria and sperm is susceptible to those same secretions 33. Sarah, a trainee of the electron microscopist at the local hospital, is reviewing some micrographs of muscle cells and macrophages (phagocytic cells). She notices that the muscle cells are loaded with mitochondria while the macrophages have abundant lysosomes. Why is this so? As muscles need more ATP for contraction And phagocytes need to digest bacteria and debris after engulfing them 34. Bradley tripped and tore one of the tendons surrounding his ankle. In anguish with pain, he asked his doctor how quickly he could expect it to heal. What do you think the doctor’s response was and why? Healing will take a long time due to poor vascularity in dense connective tissue 35. In normally circulating blood, the plasma proteins cannot leave the bloodstream easily and thus tend to remain in the blood. But if stasis (blood flow stoppage) occurs, the proteins will begin to leak out into the interstitial fluid. Explain why this leads to edema (water buildup in the tissues). Because water will go down its concentration gradient 55 56 36. Phagocytes gather in the air sacs of the lungs, especially in the lungs of smokers. What is the connection? Phagocytes remove debris from body tissues. Typically a smoker’s lung would have smoke particles needing removal THE FINA L E: M U L T IP LE C H OI CE 37. Select the best answer or answers from the choices given. 1. A cell’s plasma membrane would not contain: A. phospholipid. D. cholesterol. B. nucleic acid. E. glycolipid. 5. Which of the following are possible functions of the glycocalyx? A. Determination of blood groups B. Binding sites for toxins C. protein. 2. Which of the following would you expect to find in or on cells whose main function is absorption? A. Microvilli D. Gap junctions B. Cilia E. Secretory vesicles C. Desmosomes 3. Which cytoskeletal element interacts with myosin to produce contractile force in muscle cells? A. Microtubules B. Microfilaments C. Intermediate filaments D. None of the above 4. If a 10% sucrose solution within a semipermeable sac causes the fluid volume in the sac to increase a given amount when the sac is immersed in water, what would be the effect of replacing the sac solution with a 20% sucrose solution? A. The sac would lose fluid. C. Aiding the binding of sperm to egg D. Guiding embryonic development E. Increasing the efficiency of absorption 6. A cell stimulated to increase steroid production will have: A. abundant ribosomes. B. a rough ER. C. a smooth ER. D. a Golgi apparatus. E. abundant secretory vesicles. 7. A cell’s ability to replenish its ATP storeshas been diminished by a metabolic poison. What organelle is most likely to be affected? A. Nucleus D. Microtubule B. Plasma membrane E. Mitochondrion C. Centriole 8. The fundamental structure of the plasma membrane is determined almost exclusively by: B. The sac would gain the same amount of fluid. A. phospholipid molecules. C. The sac would gain more fluid. C. cholesterol molecules. D. There would be no effect. D. integral proteins. B. peripheral proteins. Chapter 3 Cells and Tissues 9.–11. Consider the following information for Questions 9–11: A DNA segment has this nucleotide sequence: AAGCTCTTACGAATATTC 9. Which mRNA is complementary? 15. Viewed through the microscope, most cells in this type of tissue have only a rim of cytoplasm. A. Reticular connective B. Adipose connective C. Areolar connective A. A A G C T C T T A C G A A T A T T C D. Osseous tissue B. T T C G A G A A T G C T T A T A A G E. Hyaline cartilage C. A A G C U C U U A C G A A U A U U C D. U U C G A G A A U G C U U A U A A G 10. How many amino acids are coded in this segment? A. 18 C. 6 B. 9 D. 3 11. What is the tRNA anticodon sequence for the fourth codon from the left? 16. Which type of cartilage is most abundant throughout life? A. Elastic cartilage B. Fibrocartilage C. Hyaline cartilage 17. Which of the following terms describe skeletal muscle? A. Striated A. G C. GCU B. Intercalated discs B. GC D. CGA C. Multinucleated 12. The organelle that consists of a stack of 3–10 membranous discs associated with vesicles is: A. mitochondrion. D. Voluntary E. Branching 18. Events of tissue repair include: B. smooth ER. A. regeneration. C. Golgi apparatus. B. organization. D. lysosome. C. granulation. 13. An epithelium “built” to stretch is: A. simple squamous. B. stratified squamous. C. simple cuboidal. D. fibrosis. E. inflammation. 19. Which of the following does not describe nervous tissue? D. pseudostratified. A. Cells may have long extensions E. transitional. B. When activated, shortens 14. Which of the following fibrous elements give a connective tissue high tensile strength? A. Reticular fibers B. Elastic fibers C. Collagen fibers D. Myofilaments 57 C. Found in the brain and spinal cord D. Involved in fast-acting body control SKIN AND BODY MEMBRANES 4 Body membranes, which cover body surfaces, line its cavities, and form protective sheets around organs, fall into two major categories. These are epithelial membranes (skin epidermis, mucosae, and serosae) and the connective tissue synovial membranes. Topics for review in this chapter include a comparison of structure and function of various membranes, anatomical characteristics of the skin (composed of the connective tissue dermis and the epidermis) and its derivatives, and the manner in which the skin responds to both internal and external stimuli to protect the body. CLASSIFICATION OF BODY MEMBRANES 1. Complete the following table relating to body membranes. Enter your responses in the areas left blank. Membrane Mucous Serous Cutaneous Tissue type (epithelial/connective) Epithelial sheet with underlying connective tissue (lamina propria) Epithelial Common locations Exposed body cavities Lines internal ventral body cavities and covers their organs Epithelial Skin Synovial Connective Lines cavities of synovial joints Functions Moisten Surface Moisten Surface Protection from external insults and water loss Lubrication 59 60 2. Four simplified diagrams are shown in Figure 4–1. Select different colors for the membranes listed below and use them to color the coding circles and the corresponding structures. ○ Cutaneous membrane ○ Mucosae ○ Visceral pericardium (serosa) ○ Visceral pleura (serosa) ○ Parietal pericardium (serosa) Parietal pleura (serosa) Figure 4–1 ○ Synovial membrane