BIOL 1030 – TOPIC 13 LECTURE NOTESTopic 13: Animal Form and Function (Ch. 40) – focus on vertebratesI. Organization of the vertebrate bodyA. general mammalian body architecture (mammals used as representative vertebrates)1. tube within a tube- innermost tube is digestive tract, from mouth to anus- coelom separates outer tube from digestive tract2. mammals divide their coelom into two cavities- thoracic cavity (heart and lungs)- abdominal cavity (stomach, intestines, liver, etc.)- diaphragm (muscle sheet) forms the separation, is used for breathing3. internal skeletal system- jointed bones (in most cases) that grow with the body- includes cartilage and ligaments- connected to muscles with tendons- used for movement and supportB. four levels of organization1. cell – basic unit; many types; dozens to hundreds of types in most adult vertebrates2. tissue – a group of cells similar in structure and function- most differentiate early in development from three embryonic germ layers endoderm (innermost) mesoderm ectoderm- four primary tissues in adult vertebrates epithelial connective muscle nerve3. organ – a structural and functional unit made of more than one tissue type4. organ system- a group of organs functioning together to perform a major body activity- generally 11 major organ systems are recognized; in the order that we will cover them: skeletal muscular digestive circulatory respiratory urinary or excretory endocrine reproductive nervous integumentary (not covered in this course) lymphatic/immune (not covered in this course)- see Table 40.1II. epithelial tissuesA. derived from all three germ layersB. both internal and externalC. form membranes that cover and protect all body surfaces1. barrier to water loss (see integumentary system)2. barrier to pathogens3. specializations for needed exchanges with the environmentD. form glands1. specialized for secretion (hormones, oils, enzymes, etc.)2. exocrine glands – have ducts (channels gland secretions)3. endocrine glands – ductless; secreted hormones enter blood capillariesE. unifying characteristics1. tightly bound, with little space between cells1 of 4BIOL 1030 – TOPIC 13 LECTURE NOTES2. thin (no blood vessels, creates diffusion limit)3. tissue regeneration is common through cell divisions- skin epidermis renewed every two weeks- stomach epithelium renewed every 2-3 daysF. two general classes1. simple – one cell layer thick2. stratified – several cell layers thickG. three cell shapes1. squamous – irregular, flattened shape with tapered edges2. cuboidal – about the same height, width, and depth3. columnar – taller than they are wideIII. connective tissuesA. derived from mesodermB. unifying structural characteristic: 1. cells spaced widely apart2. imbedded in an abundant extracellular matrixC. perform a variety of functions, including support, connections, and transportD. two major classes – connective tissue proper and special connective tissueE. connective tissue proper – two types, loose and dense1. loose connective tissue- cells scattered in amorphous ground substance (matrix) composed mostly of proteins- mainly under skin and between organs- provides support, food storage, and sometimes insulation- matrix is gelatinous, with three major proteins: collagen – strengthens elastin – gives elasticity reticulin – forms a supporting meshwork- cell types include, among others: fibroblasts – secrete matrix proteins mast cells – make histamine (blood vessel dilator) and heparin (anticoagulant) macrophages – defend against invading organisms adipose cells – triglyceride (fat) storage for energy2. dense connective tissue- strong (tightly packed collagen)- provides flexible, strong connections or coverings- mainly made of fibroblasts- two types, regular and irregular- dense regular connective tissue collagen fibers parallel ligaments – bone/bone connections tendons – muscle/bone connections- dense irregular connective tissue  collagen fibers with various orientations covers organs, muscles, nerves, and bonesF. specialized connective tissue – cartilage, bone, and blood1. each have unique, specialized matrix for specialized functions2. cartilage- special glycoprotein in matrix- collagen in long, parallel rays along stress lines- firm, strong, flexible tissue that does not stretch- tougher than any connective tissue proper- entire skeleton for some vertebrates- for adult humans, found in: spinal discs, joints, outer ear, nose, trachea, larynx- provides flexible, shock-absorbing support and reduces friction at joints- "model" for many bones during development- cell type: chondrocytes live in spaces called lacunae2 of 4BIOL 1030 – TOPIC 13 LECTURE NOTES living cells; exchange supplies and wastes by diffusion3. bone- most form within and replace cartilage models after deposition of hydroxyapatite crystals of calcium phosphate – provides great strength- some (like cranial bones) formed within dense irregular connective tissue instead of replacing cartilage models- collagen remains and provides flexibility; matrix is mainly calcium phosphate and collagen- cell type: osteocytes live within lacunae  have cytoplasmic processes that form a network between osteocytes; processes extend though tiny canals in the bone, or canaliculi osteocytes remain alive because of blood vessels in bone and canaliculi to those blood vessels- functions mostly as protection for organs and as a support for muscle attachment and movement4. blood- extracellular matrix is the fluid blood plasma- blood travels to nearly every part of the body in vertebrates- functions to circulate materials through the body (sugars, lipids, amino acids, oxygen, wastes, hormones, defense cells and materials)- plasma proteins include: fibrinogen – from liver; used in blood clotting albumin – from liver; used for fluid balance antibodies – from lymphocytes (specialized white blood cells); used in immune responses- cell types include: erythrocytes – red blood cells most common blood cells in mammals, lose their nucleus, mitochondria, and ER mammalian red blood cells are disc-shaped each one has about 300 million copies of the hemoglobin protein used to carry oxygen hemoglobin with oxygen is red leukocytes – white blood cells several types together only 1/1000 of red blood cell number named in