Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
BIOLOGY CONCEPTS & CONNECTIONS Fourth Edition Neil A. Campbell • Jane B. Reece • Lawrence G. Mitchell • Martha R. Taylor CHAPTER 20 Unifying Concepts of Animal Structure and Function Modules 20.1 – 20.7 From PowerPoint® Lectures for Biology: Concepts & Connections Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Climbing the Walls • The function of any part of an animal results from its unique structure • Consider the gecko, a small lizard commonly found in the tropics – A gecko can walk up a wall and across ceilings – How does it do that? Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The explanation relates to hairs, called setae, on the gecko’s toes – They are arranged in rows – Each seta ends in many split ends called spatulae, which have rounded tips Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings – The ability to “stick” to surfaces results from attractions between molecules on the spatulae and molecules on the surface – The structure of the gecko’s feet leads to a unique function Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings THE HIERARCHY OF STRUCTURAL ORGANIZATION IN AN ANIMAL 20.1 Structure fits function in the animal body • The correlation between structure and function is one of biology’s most fundamental concepts Forearm Wrist Finger 1 Palm Finger 2 Shaft Vane WING Bone structure Finger 3 Shaft Feather structure Barb Barbule Hook Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 20.1 20.2 Animal structure has a hierarchy • Structure and function are correlated at each level in the structural hierarchy of an animal’s body A. CELLULAR LEVEL: Muscle cell B. TISSUE LEVEL: Muscle tissue C. ORGAN LEVEL: Heart D. ORGAN SYSTEM LEVEL: Circulatory system E. ORGANISM LEVEL: Many organ systems functioning together Figure 20.2 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 20.3 Tissues are groups of cells with a common structure and function • A tissue is a cooperative of many similar cells that perform a specific function • Animals have four major categories of tissue – Epithelial tissue – Connective tissue – Muscle tissue – Nervous tissue Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 20.4 Epithelial tissue covers and lines the body and its parts • Epithelial tissue occurs as sheets of closely packed cells – It covers surfaces and lines internal organs and cavities – Examples: epidermis, stomach lining • The structure of each type of epithelium fits its function Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Free surface of epithelium Underlying tissue Basement Membrane (extracellular matrix) Cell nuclei A. SIMPLE SQUAMOUS EPITHELIUM (lining the air sacs of the lung) D. STRATIFIED SQUAMOUS EPITHELIUM (lining the esophagus) B. SIMPLE CUBOIDAL EPITHELIUM (forming a tube in the kidney) C. SIMPLE COLUMNAR EPITHELIUM (lining the intestine) Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 20.4 20.5 Connective tissue binds and supports other tissues • Connective tissue is characterized by sparse cells – The cells manufacture and secrete an extracellular matrix – The matrix is composed of fibers embedded in a liquid, solid, or gel Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • There are six major types of connective tissue Cell nucleus Cell Collagen fiber Collagen fibers Other fibers A. LOOSE CONNECTIVE TISSUE (under the skin) D. FIBROUS CONNECTIVE TISSUE (forming a ligament) Fat droplets Cells Cell nucleus Matrix B. ADIPOSE TISSUE E. CARTILAGE (at the end of a bone) White blood cells Central canal Matrix Red blood cells Cells Plasma C. BLOOD Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings F. BONE Figure 20.5 20.6 Muscle tissue functions in movement • Skeletal muscle is responsible for voluntary body movements • Cardiac muscle pumps blood • Smooth muscle moves the walls of internal organs such as the stomach Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Unit of muscle contraction Muscle fiber Muscle fiber Nucleus Junction between two cells Nucleus Muscle fiber Nucleus B. CARDIAC MUSCLE A. SKELETAL MUSCLE C. SMOOTH MUSCLE Figure 20.6 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 20.7 Nervous tissue forms a communication network • The branching neurons of nervous tissue transmit nerve signals that help control body activities Cell body Nucleus Cell extensions Figure 20.7 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 20.8 Several tissues are organized to form an organ • Each organ is made of several tissues that cooperate to perform specific functions Lumen Columnar epithelium Epithelial tissue Lumen Connective tissue Blood vessel Smooth muscle tissue (2 layers) Connective tissue Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 20.8 20.9 The body is a cooperative of organ systems • The level of organization higher than an organ is an organ system • Each organ system has one or more functions Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The digestive system gathers food Mouth • The respiratory system gathers oxygen Larynx Trachea Esophagus Liver Stomach Bronchus Lung Small intestine Large intestine Anus A. DIGESTIVE SYSTEM B. RESPIRATORY SYSTEM Figure 20.9A, B Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The circulatory system, aided by the lymphatic system, transports the food and oxygen • The immune system protects the body from infection and cancer Bone marrow Thymus Heart Spleen Lymph nodes Blood vessels C. CIRCULATORY SYSTEM Lymph vessels D. LYMPHATIC AND IMMUNE SYSTEMS Figure 20.9C, D Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The excretory system disposes of certain wastes Kidney Ureter Urinary bladder Urethra E. EXCRETORY SYSTEM Figure 20.9E Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The endocrine and nervous systems control and coordinate body functions Pineal gland Brain Pituitary gland Thyroid gland Sense organ Thymus gland Adrenal gland Pancreas Spinal cord Nerves Testis (male) Ovary (female) F. ENDOCRINE SYSTEM H. NERVOUS SYSTEM Figure 20.9F, H Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The integumentary system covers and protects the body Hair Cartilage Skin • The skeletal system supports and protects the body Nails Bones J. SKELETAL AND INTEGUMENTARY SYSTEMS Figure 20.9J Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The muscular system enables movement Skeletal muscles I. Muscular system Figure 20.9I Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • The reproductive system perpetuates the species MALE Penis FEMALE Seminal vesicles Ovary Oviduct Prostate gland Uterus Vas deferens Vagina Urethra G. REPRODUCTIVE SYSTEMS Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Testis Figure 20.9G 20.10 Connection: New imaging technology reveals the inner body • New technologies enable us to see body organs without surgery – Computed tomography (CT) Figure 20.10A, B Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings – Magnetic resonance imaging (MRI) – Positron-emission tomography (PET) Figure 20.10C, D Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings EXCHANGES WITH THE EXTERNAL ENVIRONMENT 20.11 Structural adaptations enhance exchange between animals and their environment • Animals are not closed systems – An animal must exchange materials and heat with its environment – This exchange must extend to the cellular level Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • Small animals with simple body construction have enough surface to meet their cells’ needs – Hydras can exchange materials with the environment though direct diffusion Mouth Diffusion Diffusion Gastrovascular cavity Two cell layers Figure 20.11A Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings • Larger, complex animals have specialized internal structures that increase surface area Mouth External environment CO2 Food O 2 Animal RESPIRATORY SYSTEM DIGESTIVE SYSTEM Cells Nutrients Interstitial fluid CIRCULATORY SYSTEM EXCRETORY SYSTEM Anus Unabsorbed matter (feces) Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Metabolic waste products (urine) Figure 20.11B • The respiratory system has an enormous internal surface area associated with a vast number of capillaries • In complex animals, the exchange of materials between blood and body cells takes place through the interstitial fluid Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 20.11C 20.12 Animals regulate their internal environment • In response to changes in external conditions, animals regulate their internal environment – They must do this to achieve homeostasis, an internal steady state External environment Internal environment Large external fluctuations Small internal fluctuations Control systems ANIMAL Cells of body Figure 20.12A, B Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 20.13 Homeostasis depends on negative feedback • Control systems sense change Signal via wire ON Set point Sensor OFF CONTROL CENTER Temperature of room Heater STIMULUS EFFECTOR Heat produced RESPONSE Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 20.13A • Negative feedback mechanisms keep fluctuations in internal conditions within the narrow range compatible with life Heat given off by 1. Blood vessels dilating 2. Sweating Blood pressure decreases Skin “Too hot” Brain Signals via blood Signals to skin via nerves CONTROL CENTER Blood temperature increases Skin Heat conserved by 1. Blood vessels constricting 2. No sweating Figure 20.13B Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings “Too cold”