Biology 123 1st EditionExam# 2 Study Guide Lectures: 1 - 6Lecture 7 (February 11)- Structure and function are closely relatedAnimal Tissue:Epithelial: Continuous, Covers body surfaces, Lines body cavities, Functions, Protection, Absorption, Secretion, Sensation Connective: Few cells and fibers scattered throughout a matrix, Intercellular fibers, Collagen,Elastic, Reticular, Specialized cells (fibroblasts & macrophages), Functions:Joins other tissues, Supports body and organs, Protects organsLecture 8(February 16)Muscular: Contracting cells, Cell = elongated muscle fiber, Contractile units = myofibrilsNervous:Neurons Transmit signals, Glial cells support and nourish neuronsLecture 9 (February 18)Homeostasis- Balanced internal environment- Keep body within a short range of values- Homeostatic mechanisms = maintain conditionsNegative Feedback - End result affects the beginning of the process in order to stop of change the effectsPositive Feedback- Causes changes to intensify instead of reversingThermoregulation- Maintaining body temperature within certain limits- Changes made despite environmental temperatureEctotherms- Body temperature depends on the temperature of the environment- Behavioral strategies used to adjust temp- Advantages: o Little energy used to maintain metabolic rateo Survive on less food- Disadvantages:o Activity limited by daily/seasonal weather conditionsEndotherms- Homeostatic mechanisms (narrow ranges)- Advantages:o High metabolic rateo Higher enzyme activity due to constant body temp- Disadvantages:o High energy costs- Integumentary Systemo Skin o Hairo Nailso Glandso Sensory receptors- Epidermiso Protects body from outer environmento Stratum corneumo Most superficialo Dead cells with keratino Stratum basaleo Cells divide and push up to surfaceo Produce keratin- Keratino Gives skin its strengtho Reduces water loss- Dermiso Dense, fibrous connective tissueo On top of subcutaneous tissue (adipose)Lecture 10 (February 25)o Metabolic rate is the total amount of energy an animal uses in a unit of time.o The "essential nutrients" for proper human nutrition include calcium, sodium,potassium, and other minerals.o Birth defects of the neural tube in humans are reduced from about 6% without folic acid supplements in the preconception interval to about 1% when the supplements were taken.o Ingestion > Digestion > absorption > eliminationo The gastrovascular cavity differs from the alimentary canal in that only the gastrovascular cavity has only a single opening. o When digested, proteins are broken down into amino acidso When digested, fats are broken down into glycerol and fatty acidso pharynx → esophagus → stomach → small intestine → large intestineo For ingested foods, the first opportunity for enzymatic digestion occurs in themoutho The lower esophageal sphincter surrounds the upper opening into the stomach. If this sphincter failed to properly constrict, there might be a problem with regurgitation of acidic stomach contents into the esophagus, commonly called "heartburno Different types of food are eaten by various groups of animals, but it is usually true that cellulose digestion in ruminant mammals occurs before the ingested foods reach the small intestine.o To survive, all animals must balance consumption of food with use and storage of nutrients.o Arteries carry blood away from the hearto Pulmonary veins carry oxygen-rich blood to the hearto a blood clot enters the cerebral circulation, blocking an artery and causing the death of brain tissueo An advantage of gas exchange in fresh water, compared with gas exchangein air, is that water loss through evaporation across the respiratory surface can be minimized.o The smallest airway through which inspired air passes before gas exchangeoccurs in the mammalian lungs is the bronchioleo An Increase in carbon dioxide in your red blood cells, which causes a drop in pH, causes your breathing to speed up.o The amount of oxygen bound to hemoglobin increases in the presence of high concentrations of oxygen.o Capillary beds are the site of nutrient and oxygen delivery to