Apparently there is no chapter/section for this in the book?
## Integument - the skin and all accessory structure (hair, feathers, scales) ## Skin - The largest vertebrate organ - major part of the integument system ## Vertebrate integument and derivatives ### Functions - Protection form abrasion - protects against water loss - barrier to disease causing pathogens - protection from UV light - temperature regulation - contains sensory receptors - excretion (limited) ### Vertebrate Integument - skin and all other accessories - skin is the largest organ o vertebrates - skin consists of 2 layers - epidermis - dermis ### Epidermis - outer layer - nutrients diffuse into the epidermis form the dermis - stratified squamous epithelial cells #### Cell types - langerhans cells - defensive cells - Melanocytes - produce pigment melanin - skin coloration - protect form UV light - Merkel cells - touch receptors - Keratinocytes - primary cell type - produce insoluble protein Keratin - amount of keratin increases from the inside to outside - keratin fill cytoplasm and impairs nutrient diffusion, cell dies ### Dermis - Inner layer of skin - thinner than dermis - highly vascularized - contains: - sensory structures - vessels - nerves - glands - Origin of hair/scales/feathers in vertebrates - Sensory structures - Meissner's corpuscles - light touch - Pacinian corpuscles - deep vibrations #### Sweat Glands - temperature regulation - produce sweat (primarily water) - evaporating cooling - release of waste ions - 2.5 million on the body - release of heat #### Sebaceous Glands - all over body, except palms and soles - large on face, neck, and upper chest - produce sebum - lubricates and soften hair and skin - water proofing in aquatic mammals ### Hypodermis - subcutaneous layer - below the dermis - not a layer of the skin - contains much adipose (fat) tissue - females have thicker layer of adipose tissue than males #### Function - body contour - insulation - support the skin # Chapter 45 & 46 ## Digestive System ### Key Concepts - Animal nutrition - general principles of digestion and absorption of food - overview of vertebrate digestive systems - mechanisms of digestion and absorption in vertebrates ## Intro to nutrition - nutrient - any substance taken in by an organism that is needed for: - survival - growth - development - tissue repair - or reproduction - nutrition - process of consuming and using food for nutrients - animals receive nutrients by consuming food ### Dietary categories - basic similarities in organ system function lead to similarities in nutritional requirements - different animal physiologies can have different nutrient demands - Herbivores - eat only plants - digestive system contains micro-organisms that help digest cellulose - Carnivores - eat only animal flesh or fluid - Omnivores - eat both ### Animals are heterotrophic - Heterotrophs - ingest feeders - cannot manufacture more food - require already synthesized organic compounds of plants of other animals to supply materials - survival - maintenance - growth - reproduction ## Gut Tracts Two types 1. Blind Gut - no cavity between gut and body wall - one opening - primitive form 2. tube-within-a-tube - flow through digestive tube - body cavity between git and body wall - separate opening (mostly) ## Digestion - the breakdown of large molecules into smaller ones ### Digestive enzymes (hydrolases) - carbohydrases - proteases - lipases - nucleases ### Food processing in animals Occurs in Five phases 1. Ingestion - food is taken into the body and moves into a digestive 2. digestion - food is broken down into smaller molecules - chemical and mechanical 3. transport 4. absorption - ions, water, and small molecules are transported into the circulatory system 5. egestion - undigested materials and other waste are passed from the body - elimination or exceretion ### Alimentary canal - digestive tract or tube - Gastrointestinal tract - Five regions of food processing - Single tube with opening at each end - contains smooth muscles in walls - lined with epithelial cells - synthesize and secrete digestive enzymes - secrete hormones - transport digestive materials - several specialized regions - different structures for different processes - storage area #### Structure of GI Tract - some general structure from midpoint of esophagus, to the anus or cloaca - lumen lined by epithelial and glandular cells - secretory cells release a protective layer of mucus - other cells release hormones - glands release enzymes, acids, water, and ions - Epithelial cells linked by tight junctions and surrounded by layers of tissue made of smooth muscle, neurons, connective tissues, and blood vessels - neurons activated by sight and smell of food and presence of food in tract #### Region of Reception ##### Buccal cavity - mouth and accessory structures - ingestion site and digestion site - chemical and mechanical - jaws, teeth, cheek muscles, tongue, and salivary glands (saliva) ##### Pharynx - back of mouth cavity - point that respiratory and digestive system cross paths #### Region of Conduction ##### Esophagus - - tube carrying materials from mouth cavity to the rest of the alimentary canal - forces/pushes good down - conducts food from pharynx to stomach - Peristalsis - rhythmic wave-like contractions which propel food forward in the GI tract - No new digestion here - only chemical continuation from buccal cavity #### Region of digestion and storage ##### Stomach (mostly) - - saclike organ evolved for storing food - muscular nature helps break up food - partial protein digestion - regulates rate of emptying into small intestine - Secretions - hydrochloric acid - kills microbes - dissolves particulate matter - secreted by parietal cells - Pepsinogen - converted to pepsin to begin protein digestion - secreted by Chief cells - Epithelium coated with an alkaline mucus - carbohydrate digestion continues from mouth - little lipid digestion happens - lumen (cavity) stomach - pepsinogen + HCL -> pepsin (for protein breakdown) #### Region of terminal digestion and absorption ##### Small intestine - near # Chapter 41 - 43 (mostly 41) ## Nervous System # Chapter 44 ## Musculoskeletal system