Animal Structures & Functions PDF

9_Animal Structures & Functions Tissue Organ and Organ Systems External Exchange and Internal Regulation © 2016 Pearson Education, Ltd.  Key Concepts There are 4 major types...

9_Animal Structures & Functions Tissue Organ and Organ Systems External Exchange and Internal Regulation © 2016 Pearson Education, Ltd.  Key Concepts There are 4 major types of animal tissues Epithelial tissue covers the body and lines its organs and cavities. Epithelial tissue is named according to the shape of the cells and the number of layer of cells Connective tissue binds and supports other tissues. There are 6 major types of connective tissues Muscle tissue functions in movements. There are 3 types of muscle tissues Nerves tissue forms the communication network. Neuron is the functional cell in nerves tissue An organ is consisting of different types of tissues An organ system is consisting of several organs. Organ systems works together to perform life function Different organ systems work together to facilitate external exchange and internal regulation © 2016 Pearson Education, Ltd. Figure 20.2 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 © 2016 Pearson Education, Ltd.  TISSUES © 2016 Pearson Education, Ltd.  Tissues are groups of cells with a common structure and function Tissues o integrated group of similar cells that perform a common function o combine to form organs Animals have four main categories of tissues: 1. epithelial tissue 2. connective tissue 3. muscle tissue 4. nervous tissue © 2016 Pearson Education, Ltd.  Overview of the 4 types of Animal Tissues Epithelial tissue Connective Muscle tissue Nervous tissue Structure Function covers the body and tissue binds and functions in forms a lines its organs and supports other movement. communication cavities. tissues. network. Sheets of closely Sparse cells in Long cells (fibers) Neurons with packed cells extracellular matrix with contractile branching proteins extensions; supporting cells Example Columnar Loose connective Skeletal muscle Neuron epithelium tissue © 2016 Pearson Education, Ltd.  Epithelial tissue covers the body and lines its organs and cavities Epithelial tissues (epithelia) - sheets of closely packed cells that o cover body surfaces o line internal organs and cavities Epithelial cells come in three shapes: 1. Squamous - like a fried egg 2. Cuboidal - cube 3. Columnar – rectangular Epithelial tissues are named according to o the number of cell layers they have – “simple” vs “stratified” o the shape of the cells on their apical surface – squamous, cuboidal, columnar © 2016 Pearson Education, Ltd. Figure 20.4 Apical surface of epithelium Basal lamina Underlying Cell tissue nuclei A Simple squamous epithelium D Stratified squamous epithelium B Simple cuboidal epithelium C Simple columnar epithelium © 2016 Pearson Education, Ltd.  Connective tissue binds and supports other tissues Connective tissue can be grouped into six major types 1. Loose connective tissue o most widespread o helps to join skin to underlying tissues 2. Fibrous connective tissue o forms tendons that attach muscle to bone 3. Adipose tissue o stores fat in large, closely packed cells held in a matrix of fibers © 2016 Pearson Education, Ltd.  Connective tissue binds and supports other tissues 4. Cartilage o is a strong and flexible skeletal material and commonly surrounds the ends of bones 5. Bone o has a matrix of collagen fibers embedded in a hard-mineral substance containing calcium, magnesium, and phosphate 6. Blood o transports substances throughout the body © 2016 Pearson Education, Ltd. Figure 20.5-0 White blood cells Red blood cell Central Plasma canal F Blood Matrix Bone- forming cells Cell E Bone nucleus Collagen fiber Cartilage- Elastic forming fibers cells A Loose connective tissue Matrix (under the skin) D Cartilage (at the end of a bone) Cell nucleus Fat droplets Collagen fibers C Adipose tissue B Fibrous connective tissue (forming a tendon) © 2016 Pearson Education, Ltd.  Muscle tissue functions in movement Muscle tissue is the most abundant tissue in most animals There are three types of vertebrate muscle tissue: 1. skeletal muscle causes voluntary movements, contains long stripe cells with multiple nuclei, found in all parts of body (connected to bones) 2. cardiac muscle caused involuntary movement in the heart, contains branched stripe cells 3. smooth muscle moves walls of internal organs such as the intestines with involuntary movements, contains long smooth cells © 2016 Pearson Education, Ltd. Figure 20.6-0 Junction between two cells Unit of muscle Muscle fiber contraction (cell) Muscle fiber Nuclei Nucleus B Cardiac muscle A Skeletal muscle Muscle fiber Nucleus © 2016 Pearson Education, Ltd. C Smooth muscle Nervous tissue forms a communication network Nervous tissue o senses stimuli o rapidly transmits information Neurons carry signals by conducting electrical impulses © 2016 Pearson Education, Ltd.  ORGANS AND ORGAN SYSTEMS © 2016 Pearson Education, Ltd.  Organs are made up of tissues - Each tissue performs specific functions The heart has extensive muscle tissue that generates contractions epithelial tissue that line the heart chambers connective tissue that make the heart elastic Nerves tissue that regulate contractions © 2016 Pearson Education, Ltd.  Organ systems work together to perform life’s functions Each organ system typically o consists of many organs o has one or more functions o works with other organ systems to create a functional organism © 2016 Pearson Education, Ltd.  Organ systems work together to perform life’s functions The circulatory system o delivers oxygen and nutrients to body cells o transports carbon dioxide to the lungs o carries metabolic wastes to the kidneys The respiratory system exchanges gases with the environment o supplying the blood with oxygen o disposing of carbon dioxide © 2016 Pearson Education, Ltd.  Organ systems work together to perform life’s functions The digestive system o ingests and digests food o absorbs nutrients o eliminates undigested material The urinary system o removes waste products from the blood o excretes urine o regulates the chemical makeup, pH, and water balance of blood © 2016 Pearson Education, Ltd.  Organ systems work together to perform life’s functions The integumentary system protects against o physical injury o infection o excessive heat or cold o drying out The skeletal system o supports the body o protects organs such as the brain and lungs o provides the framework for muscle movement © 2016 Pearson Education, Ltd. 20  Organ systems work together to perform life’s functions The muscular system o moves the body o maintains posture o produces heat The lymphatic system o Part of the immune systems, which protect the body from infection and cancer o also returns excess body fluid to the circulatory system o Absorption of lipid from the digestive system © 2016 Pearson Education, Ltd. Organ systems work together to perform life’s functions The nervous system coordinates body activities by o detecting stimuli o integrating information o directing responses The endocrine system o secretes hormones that regulate body activities The reproductive system produces o gametes and sex hormones  The female reproductive system also supports a developing embryo and produces milk © 2016 Pearson Education, Ltd.  EXTERNAL EXCHANGE & INTERNAL REGULATION © 2016 Pearson Education, Ltd.  Structural adaptations enhance exchange with the environment The respiratory system exchanges gases between the external environment and blood The digestive system acquires food and eliminates wastes The urinary system eliminates metabolic waste The circulatory system o distributes gases, nutrients, and wastes throughout the body o exchanges materials between blood and body cells through the interstitial fluid that bathes body cells The 4 systems above work together to achieve the function of exchange with the environment © 2016 Pearson Education, Ltd. Figure 20.13a EXTERNAL ENVIRONMENT CO2 Food O2 Mouth ANIMAL Respiratory Digestive system system Interstitial Heart fluid Nutrients Circulatory system Body cells Urinary Intestine system Anus Unabsorbed Metabolic waste matter (feces) products (urine) © 2016 Pearson Education, Ltd.  Animals regulate their internal environment Homeostasis is the active maintenance of a steady state within the body External environmental conditions may fluctuate wildly, but homeostatic mechanisms regulate internal conditions External environment 10C Internal −30C environment 38C 40C Large Homeostatic Small fluctuations mechanisms fluctuations © 2016 Pearson Education, Ltd.  Homeostasis depends on negative feedback Control systems o detect change and direct responses Negative-feedback mechanisms o keep internal variables steady o permit only small fluctuations around set points © 2016 Pearson Education, Ltd. Figure 20.15-0 Glands secrete sweat that The hypothalamus evaporates, cooling the body activates cooling mechanisms Blood vessels in the skin dilate, increasing heat loss Temperature The hypothalamus shuts off Temperature rises decreases the cooling mechanisms above set point Homeostasis: Body temperature approximately 37C Temperature The hypothalamus shuts off Temperature falls increases the warming mechanisms below set point Blood vessels in the skin constrict, minimizing heat loss The hypothalamus Skeletal muscles contract; activates warming shivering generates heat mechanisms © 2016 Pearson Education, Ltd.