animal structure and function. functional anatomy animal adaptations evolved through time by natural...
TRANSCRIPT
Animal Structure and Function
Functional Anatomy
• Animal adaptations evolved through time by natural selection.
• Can also adapt over short periods of time.
• Chemical energy needed for searching for food, generating body heat, regulating internal temperature, etc..
http://www.no-pest.com/CruisinForaBruisin'.JPG
• Bioenergetics - how organisms obtain, process, and use their energy resources.
• All animals have correlation between form (anatomy) and function (physiology).
http://shs.westport.k12.ct.us/mjvl/anatomy/jugglers.gif
• Tissues make up organs, organs organ systems organisms.
• Tissues - groups of cells with common structure and function.
• 4 types of tissues: epithelial, connective, muscle, nervous.
http://www.emc.maricopa.edu/faculty/farabee/biobk/stomTS.gif
• 1Epithelial – covers body, lines organs and cavities in body.
• Cells joined tightly together.
• Prevents fluid loss, invasion of microorganisms.
• Attached to underlying tissue by basement membrane.
http://www.uoguelph.ca/zoology/devobio/miller/01362fig6-1.gif
• ASimple epithelium – single-layered.
• BStratified – multi-layered.
• Shapes – cuboidal, columnar, sqamous (flattened)
• Glandular – secretes fluid – can line respiratory system (produces mucous)
• 2Connective tissue – binds, supports other tissue.
• Cells scattered throughout matrix.
• Matrix made of fibers.
• 3 types of fibers – 1collagenous (collagen – tough), 2elastic (elastin, flexible), 3reticular (thin and branched – connect to adjoining tissues)
http://www.mhhe.com/biosci/ap/histology_mh/reticct.jpg
Reticular fibers
• Major types - loose connective tissue, adipose tissue, fibrous connective tissue, cartilage, bone, and blood.
• ALoose connective - packing materials, holding organs in place.
• 2 cell types – 1Fibroblasts (secrete proteins), 2Macrophages (engulf bacteria)
http://www.sci.sdsu.edu/histology/hi_res/jpg/ct01oh.jpg
• BAdipose - insulates body, stores fuel as fat molecules.
• Contains large fat droplet that swells when fat is stored, shrinks when body uses fat as fuel.
http://www.deltagen.com/target/histologyatlas/atlas_files/musculoskeletal/adipose_tissue_white_40x.jpg
• CFibrous connective - forms tendons (muscles to bones) and ligaments (bones to bones at joints)
• DCartilage - flexible supports in certain locations, such as the nose, ears, and vertebral disks.
• Chondrocytes secrete collagen.
http://www.mhhe.com/biosci/ap/histology_mh/hcart.jpg
• EBone - mineralized connective tissue.
• Osteoblasts deposit a matrix of collagen.
• Bones consists of repeating units called osteons – has nerves and blood vessels.
http://www.texarkanacollege.edu/~mstorey/1407/bone.jpg
• FBlood - matrix liquid (plasma) has water, salts, variety of dissolved proteins.
• Suspended in plasma erythrocytes (red blood cells – carry oxygen), leukocytes (white blood cells – fight invaders) cell fragments (platelets – clotting)
http://www.kumc.edu/instruction/medicine/anatomy/histoweb/blood/large/Blood000.JPG
• 3Nervous - senses stimuli, transmits signals from one part of animal to another; functional unit – neuron
• Consists of cell body, 2+ extensions (dendrites + axons)
• Dendrites transmit nerve impulses from tips toward rest of neuron.
• Axons impulses toward another neuron or effector (muscle cell)
• 4Muscle – composed of muscle fibers capable of contracting when stimulated by nerve impulses.
• Fibers consist of contractile proteins actin and myosin.
• 3 types – skeletal, cardiac, smooth.
• ASkeletal – responsible for voluntary movement; striated.
• BSmooth – no striations; found in walls of digestive tract, urinary bladder, arteries, other internal organs – involuntary.
• CCardiac – striated and branched; forms walls of heart muscle. Cells joined by intercalated discs; involuntary.
http://www.lima.ohio-state.edu/academics/biology/images/anatomy/Smooth%20Muscle%20400X.jpg
Functional Anatomy
• Tissues organized into organs.
• Mammals – thoracic cavity – lungs, heart – separated from abdomen by diaphragm.
• Tissues can be arranged in layers.
• Organ systems carry out major body functions.
Body Plans
• Animal’s size and shape - body plans.
• Physical requirements constrain natural selection.
• Laws of hydrodynamics constrain shapes possible for aquatic organisms that swim very fast.
• Animals shape, size, determine how animal exchanges materials with surroundings.
• Protist living in water – plasma membrane large to exchange materials through diffusion.
• Multicellular organisms – many smaller cells able to exchange materials through each one.
• Flat body – maximizes exposure to surroundings; prevents internal complexity.
• Most animals complex – cells small compared to volume.
• Allows animal to not be tied to land.
• Internal organs can regulate body.
Regulating Internal Environment
• Internal environment of vertebrates – interstitial fluid.
• Exchanges nutrients and wastes.
• Animals maintain homeostasis (internal balance) even when external environment changes.
http://titlev.fiu.edu/homeostasis/images/homeostasis_home.jpg
• Major internal changes are programmed to occur, such as during pregnancy.
• Homeostatic control system has 3 parts: receptor, control center, effector.
• 1Receptor – detects change in environment.
• 2Control center – processes change.
• 3Effector – directs response.
• Two types – 1Negative feedback control – change causes reaction in opposite direction.
• Fever – causes body to sweat to bring temperature down.
• 2Positive – change causes reaction in same direction.
• Labor – release in oxytocin increases uterine contractions.
• Regulated change important to survival.
• Can by cyclical (hormones), or reactive (fever)
• Internal regulation expensive in energy.
http://web.lemoyne.edu/~hevern/psy340/graphics/negative.feedback.jpg
Bioenergetics• Chemical energy needed for
growth, repair, regulation, reproduction.
• Food digested through hydrolysis, nutrients absorbed by cells.
• ATP use creates heat that is lost to environment.
• Energy left over – used for bioenergetics.
http://www.topicazos.com/fotos/digestion.jpg
• Bioenergetics - synthesis of storage material, production of reproductive structures, including gametes.
• Flow of energy through animal – sets limits on growth, behavior, reproduction, energy needs.
• Amount of energy used in given time – metabolic rate.
• Measured in calories.
• Metabolic rate can be determined by measuring amount of heat produced.
• 2 metabolic strategies used by animals.
http://www.nsf.gov/news/speeches/colwell/rc01aibs/img004.jpg
• 1Endothermic – birds, mammals - maintain body temperature at certain level with heat generated by metabolism.
• High-energy strategy – allows for intense activity.
• 2Ectothermic – reptiles, amphibians - do not produce enough metabolic heat to effect body temperature.
• Need less energy.
http://www.kidzone.ws/animals/polar_bear_2.jpg
• Amount of energy needed to maintain homeostasis inversely proportionate (per gram) to size.
• Each gram of a mouse consumes more energy than elephant.
• Smaller animal – higher metabolic rate to deliver oxygen, energy.
http://jan.ucc.nau.edu/~sll/images/Elephant-mouse.jpg
• Metabolic rate of nongrowing endotherm at rest, with empty stomach, experiencing no stress -basal metabolic rate (BMR)
• Metabolic rate of resting, fasting, nonstressed ectotherm - standard metabolic rate (SMR).
http://biology.unm.edu/jhbrown/Images/ScalingGraph.GIF
• Behavior above BMR or SMR consumes energy.
• Maximal BMR determines amount of energy expended.
• Ectotherms cannot do long, intense activity.
• BMR of human much higher than SMR of alligator.
• Factors influence BMR - age, sex, size, body and environmental temperatures, quality and quantity of food, activity level, oxygen availability, hormonal balance, time of day.
• How energy used varies among species.
• Endotherms need more energy; smaller animals need more energy.
• Human female spends large fraction of energy budget for BMR, relatively little for activity and temperature regulation.
• Male penguin spends larger fraction of energy expenditures for activity - must swim to catch food.