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1 Review for Midterm and Final Intro to Bio List and describe steps to the Scientific Method. What is a control variable, dependent (responding) variable, independent (manipulated) variable? Set up a controlled experiment and identify each of the above variables. Metric system. List the basic conversions within the metric system and what units apply to length, mass, volume, density and temperature. Know how to convert within the metric system. List/Explain the characteristics of living things. Be able to determine if something is living by applying each of the characteristics. Differentiate between viruses and cells/living things based on characteristics of life. List the parts of the compound light microscope and their function. List/be familiar with tools of the biologist, how they are used and what they are used for. Tool Function 2 Matter and chemistry List and describe the parts of the atom. Differentiate between atomic number and mass number. What are isotopes? Compare ionic and covalent bonds. Label and give an example of each using electron dots. Define the following classifications of matter: Mixture Solution Solvent Solute Suspension What is the pH scale and what does it measure? Draw a pH scale and label acids, bases (alkaline), and neutral. List characteristics of acids and relate to H+ and OH- concentrations List characteristics of bases and relate to H+ and OH- concentrations Organic compound: Inorganic compound: Polymerization: Monomer: Polymer: 3 Why is water considered the universal solvent? Include a diagram with explanation. Biochemistry relate to (catabolic/exogonic) and (anabolic/endogonic) reactions. Explain and use labeled diagrams depicting dehydration synthesis and hydrolysis as it relates to the following organic compounds: *Carbohydrates (monosaccharide, disaccharide, polysaccharide) *Lipids and fats. Also, what are characteristics of fats? (Remember they’re waxy) Explain/Use labeled diagram: What constitutes a saturated, unsaturated and polyunsaturated fat? *Proteins *Nucleic acids (No diagram required) What is an enzyme? How does it work? What is its purpose? What 2 main things are they dependent upon and how do they affect enzyme function? (Be able to interpret graphic data of enzyme function based on the above). Define active site and substrate (include a labeled diagram for anabolic or catabolic). 4 Cell structure and Function State the cell theory. Compare and contrast plant and animal cell structure. Draw a diagram & label. Compare and contrast prokaryotes and eukaryotes. Draw a diagram & label. Describe the function of the following cell parts and organelles. ID what is found in plant and/or animal cells. Be able to identify plant vs animal cells. Draw a picture of each if it helps. *Cell membrane *Cell wall *Nucleus *Nucleolus *Nuclear envelope *Cytoplasm *Mitochondria (including structure) *Chloroplast (including structure) *Ribosomes *Endoplasmic reticulum (rough & smooth) *Golgi apparatus *Lysosomes *Vacuoles *Plastids (leucoplast and chromoplast. You already did chloroplast above)! *Cytoskeleton *Centrioles 5 Explain/Describe the various types of transport *Passive transport Diffusion Osmosis Facilitated diffusion *Active transport Endocytosis (phagocytosis and pinocytosis) Exocytosis (secretions vs. excretions) List and explain the levels of organization from cells to organ systems. Classification Who came up with the system of binomial nomenclature and why? List the taxons from largest to smallest. Describe the characteristics of the 6 Kingdoms and further classify them into Domains and 5 Kingdoms. (prokaryote vs eukaryote, cell structures, autotroph vs heterotroph (modes of nutrition), mobile vs sessile, multicellular vs unicellular, examples). Kingdom Cell Type Prokaryote Eukaryote Cell Structures Eubacteria Archaebacteria Protista Fungi Animalia Eukaryote Cell walls with peptideolycan Cell walls without peptideo-glycan Number of Cells Unicellular or Multicellular Some cell walls of cellulose Some with chloroplasts Unicellular but some multicelular No cell walls or chloroplasts Mostly multicellular Some unicellular Mode of Nutrition Autotroph & or Heterotroph Mobility Sessile or Mobile Examples Plantae Some mobile, (Protozoans, Ex. amoeba Paramecium, euglena) some sessile Live in harsh environments methanogens Multicellular Ex. Unicellular Ex. 6 Compare and contrast viruses and cells in terms of living/nonliving, genetic material and reproduction. Viruses Cells How can viruses and bacteria be helpful? How are they pathogens (harmful/disease causing)? Viruses Bacteria Helpful: Helpful: Harmful/pathogenic: Harmful/pathogenic: Protein Synthesis What were the major contributions of the following scientists? Avery, Mccarty, Macleod Hershey and Chase Rosalind Franklin & Wilkins Chargaff James Watson and Francis Crick What is the function of DNA? (3 basics) What is DNA made up of? What is the shape of DNA? List the 4 DNA nitrogenous bases, how they pair, and what type of bond forms. List the parts of the DNA nucleotide. List the steps involved in DNA Replication (DNA Synthesis) and represent them in a diagram. Label the components. List the 3 main types of RNA and their function. 7 Compare and contrast DNA and RNA. DNA is located in the ___________ of the cell. It contains the genetic information. ____RNA makes a complimentary copy of the DNA in the process of _______________. It then carries it to the _____________ (part of the cell…why?) where it binds to _________RNA which has a small and large subunit. mRNA has triplets called__________that are bonded to the tRNA’s________ __________ in the process of ________________. Each tRNA carries a specific _________ _________ which through the process of dehydration synthesis forms a ___________________. Protein synthesis occurs in the ________________ at the ___________. How is the message sent to start or stop protein synthesis? Enzyme used in the synthesis of mRNA. What is its function? If a DNA molecule reads A T G C C T, what will be the mRNA bases that will pair up with it? Using the above mRNA molecule, what will be the tRNA bases that will pair up with the mRNA? _ _ _ _ _ _ What will be the amino acid sequence? (use the genetic code chart). Why are substitutions (point mutations) not as potentially harmful as frame shift mutations? Explain, using the above sequence for both. Define and state location for the following: Replication: Transcription: Translation: Mitosis and Meiosis What types of cells undergo mitosis? Why must cells divide? 8 What is the cell cycle and how is it divided up? What is the longest part? Compare and contrast mitosis and meiosis. List, diagram, and explain the stages (in order) of mitosis- cell division. What cells undergo meiosis? List, diagram, and explain the stages of meiosis. In which stage of meiosis does crossing over, shuffling and synapsis occur? How does sexual reproduction and these events contribute to increased diversity? Why is meiosis necessary for sexual reproduction? Explain 2n (diploid) and n (haploid) chromosome number. If a cell has a 2N diploid number of 12, how many cells and chromosomes are present in each cell after mitosis? after meiosis? 9 Define homologous pair. What is a zygote? Compare and contrast spermatogenesis and oogenesis. Genetics Who was Gregor Mendell? What is an allele? What is a hybrid? How did he know the recessive trait did not disappear? What is a Punnet Square and how is it used? Define the following: Principle of Inheritance: Prinicple of Dominance: Segregation of alleles: Independent assortment: Review study guides, notes and examples for potential crosses. Be able to complete 1 and 2 trait crosses and predict genotype and phenotype probability for the following modes of inheritance: Dominance, Co-Dominance, Incomplete Dominance, SeX Linked. Cross a heterozygous tall plant with a short plant. (Tall is dominant). Punnet square: Genotype ratio: Phenotype ratio: Cross 2 people who are heterozygous for brown eyes. Punnet square: Genotype ratio: Phenotype ratio: 10 Cross a plant that is heterozygous for Round and Yellow peas, with a plant that is wrinkled and heterozygous for yellow peas. (Round and Yellow are dominant, wrinkled and green are recessive). Punnet square: Genotype ratio: Phenotype ratio: In the cross of AaBbCc Show your work. X AaBbCc what is the probability of getting AABbCc? Mary: heterozygous for brown eyes, has blond hair and has blood type A (her dad was O) Dave: blue eyes, is heterozygous for brown hair and has blood type B (his mom was O) They have a child Dudley. Show the Punnet square, genotype and phenotype ratio for Dudley for the following: Eye color Hair Color G: P: G: P: Blood Type G: P: The gene for color blindness is seX-linked. What is the probability that a child will be colorblind if the mother is a carrier and the father has normal vision? Punnet square: Genotype ratio: Phenotype ratio: Name and describe 3 seX-linked genetic disorders. * * * Why is it more common among males to inherit a seX linked disorder? What is a pedigree? Be able to interpret one and determine probable mode of inheritance.. 11 What is a Karyotype? What are autosomes and how many do you have? How many sex chromosomes? How is sex determined? What is nondysjunction? What is Down’s syndrome? Define the following using chromosome number and sex chromosomes. Kleinfelter’s syndrome: Turner’s syndrome: In incomplete dominance, what happens when you cross a red carnation and a white carnation? How can you tell incomplete dominance has occurred? Punnet square: Genotype ratio: Phenotype ratio: What happens when you cross the above F1 offspring with each other? Show your Punnet square. In some varieties of chickens, black feathers are co-dominant with white feathers. What happens when you cross a black chicken with a white chicken? Show your Punnet square: How do you know this is co-dominance? Genotype: Phenotype: Define the following genetic terms: Test Cross: Multiple alleles: Polygenic traits: Polyploidy: Mutation: 12 Point Mutation: Frame-shift Mutation: (duplication or deletion) Genetic engineering: Ecology and Power Point information Put the following terms in order from smallest to largest. population, ecosystem, species, community. List 4 examples of biotic factors and abiotic factors in a ecosystem of your choice. Draw a food web for your aboce ecosystem with 4 producers, 3 primary consumers, 2 secondary consumers and 1 tertiary consumer, then put them in a labeled ecological pyramid. Remove one of the organisms and explain what will happen to the food web as a result? If the producers have 1000 calories of energy, how much energy do tertiary consumer have? Why? (How much energy is transferred to the next trophic level)? Why are there usually not more that 4 or 5 trophic levels? Define the following: Carnivore: Herbivore: Omnivore: Decomposer: Detritovore: Define and give an example of the following symbiotic relationships Parasitism: Commensalism: Mutualism: Why is predation NOT parasitism? What are the 2 types of succession, which takes longer and why? 13 What is a climax community? What is carrying capacity? Draw a graph of exponential growth. Using the hare and fox, explain what causes the fluctuations in a predator-prey population? Differentiate between a density dependent limiting factor and a density independent limiting factor. Describe/Diagram/Label the following nutrient cycles using terms & arrows. Carbon cycle Water cycle Nitrogen cycle Phosphorus cycle Oxygen Cycle Explain the laws of conservation as they relate to mass, matter and energy. 14 Photosynthesis and Cell respiration Compare and contrast the mitochondria and chloroplast Define the following: Photosynthesis: Cell Respiration: Autotroph: Heterotroph: How is energy stored and released in ATP? Compare and contrast photosynthesis and cell respiration The pigment chlorophyll absorbs ________ and ________ wavelengths and reflects _________ and _________ wavelengths. Describe/Draw and label the structure of the chloroplast Using a diagram, show/label the overview of photosynthesis that includes the light and dark reactions. Name an electron acceptor ___________and carrier ___________ in the process? In general, what happens in the light (dependent) reactions? Bullet your response. In general, what happens in the dark reactions (Calvin Cycle)? Bullet your response. What drives the dark reaction? Hint: Although it not light dependent, what is it dependent on? 15 Diagram an overview of cell respiration showing Glycolysis, Kreb’s (Citric Acid) Cycle and Electron Transport Chain (ETC). In general, what happens in glycolysis and where does it take place? In general, what happens in the Kreb’s (Citric Acid) Cycle, and where does it take place? In general, what happens in the ETC, where does it take place and what must be present. Why? What is fermentation? What are the 2 main types and what are their reactions? What are the electron acceptors in cell respiration? (abbreviations) What are the electron carriers in cell respiration? (abbreviations) Evolution Define evolution: List and describe/explain 5 characteristics that support evolution. * * * * * 16 Differentiate between gradualism and punctuated equilibrium. In terms of the Panda’s thumb, or giraffe’s long neck, describe both Lamark and Darwin’s evolutionary theories. Lamarck: Darwin: Give an example of natural selection. Explain, using and example, how geographic isolation can lead to reproductive isolation and speciation? Define and give an example of microevolution. What is a hominid? What is adaptive radiation? Compare divergent and convergent evolution. Give examples of each. Divergent: Convergent: Define and give an example of the following. Homologous structures: Ex. Analogous structures: Ex. What is genetic drift? Distinguish between evolutionary theory and evolutionary fact. List 4 different types of fossils and how they are formed, include sedimentary rock. Compare absolute and relative dating. 17 Human Systems/Review Notes One hundred trillion cells make up body Every cell independent unity & part of larger unit Levels of organization in a multi-cellular organism Cells Basic unit of S&F Specialized to perform certain Fx Tissues Group of cells that perform single Fx 4 Basic Types * Epithelial: glands & tissue that cover in/exterior body surfaces (skin, membranes) * Connective: provides support for body & connect parts (bone, blood) * Nerve: transmit nerve impulses thru body *Muscle: cardiac, skeletal, smooth allows mvmt & produces heat Organs Group of different tissue work together to perform single Fx Ex. eye (epithelial, nervous, muscle, connective Fx sight Organ System Group of organs work together to perform complex Fxs Homeostasis process of maintaining internal, relatively constant/balanced conditions despite changes in external environment Based on – Feedback Inhibition/Physiological loop Ex. home thermostat set at 700C. Temp drops <700C furnace turns on, runs until temp =700C & furnace turns off. When temp falls <700C furnace turns on & cycle repeats Ex. Body Temp maintained by hypothalamus Cold neurons detect ↓ temp hypothalamus releases chemicals that ↑ chemical Rxs produce heat (arrector pili) muscles contract form goose bumps produce heat BT ↑ (- feedback) ↓ hypothalamus activity Hot neurons detect ↑ in temp hypothalamus releases chemicals that ↓ chemical Rxs (sluggish/tired produce less heat) vessels dilate closer to skin releases heat prespire evaporates releases heat BT↓ (- feedback) ↑ increases hypothalamus activity Consult text for overview diagrams of the following Nervous System Structures: brain, spinal cord, peripheral nerves Fx: recognizes & coordinates body’s response to changes in its in/external environments Respiratory System Structures: nose, pharynx, larynx, trachea, bronchi, bronchioles, lungs Fx: provides O2 for C.R. & removes CO2 from body 18 Digestive System Structures: mouth, pharynx, stomach, sm/lg intestines, rectum Fx: converts foods into simple molecules that can be used by cells Absorbs food/nutrients, eliminates wastes Excretory System Structures: skin, lungs, kidneys, urinary bladder, urethra Fx: eliminates waste products to help maintain homeostasis Skeletal System Structures: bones, cartilage, ligaments (bone to bone), tendons (muscle to bone) Fx: support body, protect internal organs, allows mvmt, stores mineral reserves, site of blood formation Muscular System Structures: skeletal muscle, smooth, muscle, cardiac muscle Fx: works w/ skeletal system to produce mvmt, helps circulate blood & move food thru digestive system Circulatory System Structures: heart, blood vessels, blood Fx: brings O2, nutrients, hormones to cells, fights infection/clotting, removes cell wastes (incl CO2), helps regulate body temp Endocrine System Structures: hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas, ovaries/testes Fx: controls growth, development, metabolism, maintains homeostasis (chem. messengers/ducts) Reproductive System Structures: testes, epidydimis, vas deferens, urethra, penis males ovaries, fallopian tubes, uterus, vagina females Fx: Produces reproductive cells, female also nurtures/protects embryo Nervous System NS controls & coordinates fxs throughout body & responds to in/external stimuli Neurons: (nerve cells) basic unit of S&F of NS Cells that transmit electrical signals (impulses) to carry messages rapid & short duration (vs endocrine’s slow release of chemical messengers that act over lg time) 3 Types of neurons based on direction impulse carried Sensory Neurons: carry impulses from sense organs spinal cord/brain Motor Neurons: carry impulses from brain/spinal cord muscles & glands Interneurons: connect sensory & motor neurons & carry impulses between them Parts of a neuron Cell body: contains nucleus & cytoplasm & performs most of cell’s metabolism Dendrites: extensions from cell body, carry impulses from environment or other neurons towards cell body Axons: long fiber carries impulses away from cell body axon terminals 19 (Axons & dendrites clustered into bundles Nerves) Myelin Sheath: on some neurons (vertebrates/large) insulates axon w/ gaps called nodes where membrane is exposed Impulse moves along axon & jumps note to node ↑ impulse speed The Nerve Impulse: flow of electrical current Resting Neuron: Outside + Inside -- difference in charge electrically charged Resting Potential Na+ ions pumped out and K+ ions pumped in (Na/K Pump run by ATP Active Transport) Neuron Membrane selectively permeable to Na+ and K+ ions but more K+ leaks out than Na+ in creates overall – charge inside neuron c.m (other – charged ions present, Ex. Cl-) Moving Impulse: begins when a neuron is stimulated by another neuron or environment sudden reversal of membrane potential (electrical charge) Self propagating: impulse at any point along cm causes impulse at next point on cm Impulse travels rapidly down axon away from cell body Steps of the Action Potential Neuron c.m. has protein channels/gates that allow ions to pass thru normally closed Leading edge of impulse Na+ gates open Na+ ions flow inside c.m Reversal of charges 20 Inside more + than outsideAction Potential / Nerve Impulse As Impulse passes, K+ gates open and K+ ions flow out Restores Resting Potential (- inside + outside) Threshold: Minimal level of a stimulus required to activate neuron All or none principle Impulse moves in 1 direction b/c Na+ gates close and cannot be re-opened for short time Link to Action Potential Animation w/ Saltatory Conduction http://www.blackwellpublishing.com/matthews/actionp.html Resting Potential Action Potential Na+ rush in Depolarization Re-polarization – Action Potential – Resting Potential The Synapse (cleft/gap between neuron and another cell) Impulse reaches axon terminals w/ vesicles/sacs filled w/ neurotransmitters Neurotransmitters chemicals used by neuron to transmit impulse across synapse to another cell (ex. another type of neuron or muscle cell) Impulse arrives at axon terminal Vesicles release neurotransmitters into synaptic cleft/gap Neurotransmitters diffuse across synaptic cleft & attach to receptors on next cell Stimulus causes Na+ ions to rush into cell If threshold met/exceeded new impulse begins or Rx occurs (ex. muscle contraction) Neurotransmitters quickly broken ↓ by enzymes taken up & recycled by axon terminal diffuse away ???How do you think abnormal levels of neurotransmitters affect Fx of N.S? (Either ↑ or ↓ transmission of nerve impulse) 21 Divisions of the Nervous System Nervous System 2 main subdivisions CNS (control center of the body) PNS (relays commands from CNS and receives info from environment) CNS Brain and Spinal Cord Relays messages, processes & analyses info Skull & Vertebrae in spinal column protect brain & spinal cord Brain & Spinal Cord wrapped in 3 layers of Connective Tissue Meninges (outer) Dura, (middle) Arachnoid, (inner) Pia matter Between Meninges & CNS tissue space filled w/ CSF bathes brain & spinal cord Shock absorber—Protects Allows exchange of nutrients & waste products between blood & nervous tissue The Brain: where impulses flow to & from which impulses originate from part of brain damaged determine effects Figure 35-9 The Brain Section 35-3 Cerebrum Thalamus Pineal gland Hypothalamus Cerebellum Pituitary gland Pons Medulla oblongata Spinal cord Go to Section: Cerebrum (lgst. most prominent part of brain) Voluntary/Conscious activities Intelligence, Learning. Judgment Deep groove divides cerebrum into LT & RT hemispheres Hemispheres connected by band of tissue corpus callosum Folds/Grooves ↑ surface area 22 Each hemisphere of cerebrum divided into lobes (after skull bones that Frontal Lobe (front) voluntary muscle mvmt cover them) Parietal Lobe (behind frontal) Temporal Lobe (sides) Occipital Lobe (back) Each ½ of cerebrum deals w/ opposite side of body Sensations from LT side of body RT hemisphere Sensations from RT side of body LT hemisphere Commands to move muscles also opposite LT Hemisphere controls RT side of body RT Hemisphere controls LT side of body Studies suggest RT Hemisphere associated w/ creativity & artistic ability LT Hemisphere associated w/ analytical & mathematical ability 2 Layers of Cerebrum (outer) Cerebral Cortex gray matter densely pkd nerve cell bodies Processes info from sense organs & controls body mvmts (inner) white matter (bundles of axons & myelin sheaths) connects cerebral cortex & brain stem Cerebellum (2nd lgst region of brain) Located at back of skull (Commands to move from Cerebral Cortex but) Cerebellum coordinates & balances actions of muscles smooth & efficient mvmt/graceful Brain Stem Connects brain & spinal cord Located just below cerebellum Midbrain - Pons - Medulla Oblongata Switchboard—regulates flow of info from brain & rest of body Fx’s regulates BP, heart rate, breathing, swallowing Thalamus & Hypothalamus (between brain stem & cerebrum) Thalamus: receives messages from all sensory receptors throughout body then relays info to proper region of cerebrum for further processing Hypothalamus: (just below thalamus) Control center for hunger, thirst, fatigue, anger, BT Controls coordination of NS & Endocrine System 23 Spinal Cord: main communications link between brain & rest of body 31 prs of spinal nerves branch out from spinal cord connect brain to all parts of body Reflex: quick, automatic response to stimulus (ex. sneezing, blinking, knee jerk) Allows body to respond to danger fast w/o thinking! Processed directly in/out spinal cord then to brain Sensory neuron spinal cord (Interneuron) Motor Neuron response effector/ muscle 24 The Peripheral Nervous System: lies outside CNS Consists of nerves & associated cells that are not part of brain & spinal cord Cranial nerves that pass thru skull openings stimulate regions of head & neck Spinal Nerves Ganglia (collections of nerve cell bodies) Sensory Division of PNS: transmits impulses from sense organs CNS Motor Division of PNS: transmits impulses from CNS to muscles/glands (effectors) Motor Division of PNS divided into Somatic NS: regulates activities under conscious control (ex. mvmt of skeletal muscle uses motor neurons of Somatic NS) Some somatic nerves also involved w/ reflex arc (act w/o conscious control Reflex Arc (Rx before message reaches CNS) sensory receptor sensory neuron (interneuron in spinal cord sometimes) motor neuron effector (muscle for mvmt) Autonomic NS: regulates autonomic/involuntary body fxs not under conscious control (Ex. pupil reflex, digestion w/ sm muscle) Opposing effects Sympathetic NS speeds up Rxs (gas pedal) Parasympathetic slows down Rxs (brake pedal) needed for homeostasis between body systems! Ex. Running Sympathetic NS speeds up heart rate & flow of blood to skeletal muscles, stimulates sweat glands & adrenal glands Parasympathetic NS slows down contractions of smooth muscles in digestive system stop running what happens?? Parasympathetic NS slows down heart rate & flow of blood to skeletal muscles Sympathetic NS increases contractions of smooth muscles in digestive system 25 The Skeletal System Skeleton composed of connective tissue called bone, cartilage, ligaments Structure Function: structure of hip bones mvmt walk upright also, male/female different fx’s structure of hand bones dexterity opposable thumbs grasp size/shape of skull well developed brain Skeleton: supports body protects internal organs provides mvmt stores mineral reserves site for blood cell formation structure is strong/flexible w/o ↑ weight Ex. skull/brain rib cage/heart & lungs provides system of levers muscle use to mvmt Ca, salts, P blood cells produced in soft red marrow that fills internal cavities of some bones (long and flat) 206 bones make up axial and appendicular skeleton Axial skeleton supports central axis of body skull, vertebral column, rib cage Appendicular skeleton arms, legs, pelvis, shoulder 26 Structure of bones: Network of living cells & protein fibers surrounded by Ca salts Periosteum: tough layer of connective tissue that surrounds bone Blood vessels pass thru carry O2 & nutrients to bone beneath Beneath periosteum Compact Bone: Dense but not solid b/c of network Haversian Canals that contain blood vessels & nerves Spongy Bone: less dense & found inside the outer layer of compact bone found in the ends of long bones & in middle of short flat bones lattice like network ↑ strength w/o adding lots of weight Osteocytes: bone cells imbedded in matrix of Havesian System Osteoclasts: break bone ↓ Osteoblasts: produce bone Despite fact that we stop growing, constant bone loss/bone repair continues ue ccocontinues Bone Marrow: soft tissue w/in bone cavities Yellow Marrow mostly fat cells Red Marrow produces RBC’s, some WBC’s & Plts Development of Bones Embryos mostly cartilage connective tissue w/ cells scattered in network of tough collagen & flexible elastin fibers w/ No blood vessels relies on diffusion of nutrients from surrounding blood vessels Ossification: process of replacing cartilage w/ bone begins before birth Osteoblasts secrete mineral deposits that replace cartilage osteocytes (when osteoblasts surrounded by bone tissue they mature into osteocytes) 27 Long bones w/ growth plates at ends Growth of cartilage at ends bones lengthen cartilage replaced by bone tissue S&F Cartilage (flexibility) found in nose, ears & rib cage allows rib cage to move during breathing Types of Joints Determined by range of mvmt Immovable: Fixed, interlocked, No mvmt skull Slightly Movable: Permit small amt of restricted mvmt between vertebrae pubic symphisis Freely Movable: Permit mvmt in 1 or more directions Grouped according to structure & types of mvmt Ball & Socket permit mvmt in many directions (widest range of mvmt) hip/shoulder Hinge permit back & forth mvmt (in 2 directions) Pivot allow bone to rotate around another (neck atlas & axis vertebrae) Saddle permit bone to slide in 2 directions (thumb) Structure of Joints (S&F) Freely movable joints cartilage covers bones where they come together protects bones ↓ friction fibrous joint capsule helps hold joint together but permit mvmt w/ synovial fluid lubricates Some freely movable joints bursa sac filled w/ synovial fluid ↓friction & shock absorber Ligaments: connect bone to bone in a joint Tendons: connect muscle to bone Skeletal System Disorders Osteoporosis: weakening of bones due to Ca loss * older women during menopause Ca requirements ↑ Ca removed from bones makes them weak/brittle fractures ↑ Ca intake, weight bearing exercises, Vit D helps Ca absorption 28 The Muscular System Muscular System Function: Mvmt Heat production 40% of weight = muscle 3 Types of muscle tissue w/ specialized fxs (StructureFunction) Skeletal Muscle: (striated/voluntary) attached to bones produce voluntary (conscious NS) mvmt of skeletal system dark bands striations long w/ many nuclei (1mm-30cm) referred to as muscle fibers complete skeletal muscle consists of muscle fibers, connective tissue, blood vessels & nerves Smooth Muscle: (non-striated/involuntary) spindle shaped 1 nucleus found in walls of hollow structures (stomach), blood vessels & digestive tract control blood flow thru circulatory system, pupil size, mvmt of food thru digestive tract gap junctions between smooth muscle cells allow impulses to move from 1 cell to next w/o NS stimulation Cardiac (heart) Muscle: (striated/involuntary) branched for spreading contraction 1-2 nuclei Involuntary Striated like skeletal perform hard mechanical pumping Involuntary like smooth keeps beating w/o voluntary control http://www.bioedonline.org/slides/slide01.cfm?tk=5&dpg=10 29 Muscle Contraction (of skeletal muscle) S&F cardiac similar b/c of striations but not smooth which provides for different type of contraction Skeletal Muscle has bundles of muscle fibers (muscle cells) that are made up of myofibrils/myofilaments thin filaments contain protein actin thick filaments contain protein myosin Striations in skeletal muscle from alternating actin/myosin filaments Filaments arranged in units called sarcomeres separated by Z lines When muscle relaxed, no thin filaments in center of sarcomere Sliding Filament Model/Theory Muscle contraction thin actin filaments slide over thick myosin filaments Thick myosin filament has knobs that form a cross bridge w/ binding sites on thin actin filament actin filament slides towards center of sarcomere distance between Z lines ↓ (knob/cross bridge detaches from actin, process repeats) muscle contract shortens/thickens ATP provides energy for muscle contraction (aerobic CR & lactic acid fermentation) Control of Muscle Contraction Motor neurons connect CNS to skeletal muscle cells at neuromuscular junction Impulse vesicles in axon terminals release neurotransmitter acetylcholine diffuses across synapse to cm of muscle fiber causes release of Ca2+ ions trigger thin actin & thick myosin to interact muscle contraction 30 Muscle cell remains contracted until release of acetylcholine stops & enzyme produced at axon terminals destroys acetylcholine, it diffuses away or is reabsorbed by axon terminal Cross bridges stop forming muscle contraction ends. Strong vs Weak contraction: result of # of muscle cells contracting within muscle Muscle building adds myofibrils to muscle cell hypertrophy Muscle loss myofibrils in muscle cell lose myofibrils atrophy Spinal Cord injury: Injury interrupts pathway of impulses from brain nerves that controlmuscles Without impulses from nerves muscles can’t contract paralysis How Muscles and Bones Interact Skeletal muscles: generate force & produce mvmt by contracting/ pulling on bones joined to bones by tough connective tissue tendons Tendons attach muscle to bone & pull on bones so they work like levers joint fxs as fulcrum (fixed point around which lever moves around) muscle provides force Several muscles surround each joint that pull in different directions Most skeletal muscles work in opposing pairs: one muscle contracts while other relaxes Biceps contracts bends/flexes elbow joint Triceps/relaxed Triceps contract opens/extends elbow Biceps/relaxed Controlled mvmt requires action of both muscle groups antagonists Hold tennis racket/violin both biceps & triceps must contract in balance Brain must learn how to work opposing muscle pairs for precise joint mvmt 31 Exercise & Health Partial contraction resting muscle tone & posture even when you are relaxed! Regular exercise maintains muscle strength & flexibility firm & ↑ in size by adding actin & myosin protein filaments excessive hypertrophy muscles not used ↓ in size by losing actin & myosin protein filaments atrophy Aerobic exercise efficient body systems heart & lungs ↑ efficiency ↑ endurance so less fatigue w/ activity Regular exercise strengthens bones thicker/stronger injury less likely Resistance exercise ↑ muscle size & strength ↓ body fat ↑ muscle mass ↑ coordination & flexibility The Circulatory System Each breath brings O2 into Respiratory System needed by cells in body (to produce ATP thru CR) Beating heart force that moves O2 rich blood thru Circulatory System Circulatory & Respiratory Systems supply cells throughout body w/ nutrients & O2 and w/ Excretory System filter blood to remove wastes from cell metabolism Fx’s of Circulatory System (needed in large organisms humans/vertebrates vs sm organisms diffusion) Closed system circulating blood contained w/in vessels Circulatory System Structures: Heart that pumps Blood thru Vessels Heart: Size of fist Enclosed in protective tissue Pericardium 2 thin layers of epithelial & connective tissue surround myocardium (heart muscle) Contractions of myocardium pump blood thru circulatory system Avg 72 contractions/min w/ 70ml/contraction 5L blood/min Septum: Divides heart into RT/LT prevents mixing of O2 rich on LT w/ deO2 on RT 32 Anatomical Rt side Anatomical Lt side septum 4 Chambers 2 Atrium/Atria: Upper receiving chambers 2 Ventricles: Lower discharging chambers Circulation Thru the Body Heart Fx’s as 2 separate pumps: Pulmonary Circulation: RT side of heart pumps deO2 blood to Lungs In lungs CO2 out & O2 in (diffusion) O2 rich blood flows to LT side of heart Systemic Circulation: Blood pumped from LT side of heart Body Blood that returns to RT side of heart deO2 (O2 poor) b/c cells absorbed O2 & loaded blood w/ CO2 from cell metabolism/CR via diffusion Circulation thru Heart (1 way flow efficient) Blood enters heart thru LT & RT atria (receiving chambers) Heart contracts blood flows into ventricles either body (systemic) or lungs (pulmonary) 33 Valves: Fx Keeps blood moving in 1 direction 2 flaps of connective tissue between atria & ventricles (AV valves) Tricuspid between RT atrium & RT ventricle Bicuspid/Mitral between LT atrium & LT ventricle Blood moving from atria ventricles keeps valves open When ventricles contract AV valves close LUB & prevent backflow into atria 2 valves at ventricle exits (Semilunar Valves) Pulmonary Valve between RT ventricle & Pulmonary Artery Aortic Valve between LT ventricle & aorta DUB when semilunar valves close & prevent backflow into ventricles Damaged valves repaired b/c ↓ efficiecy Blood flow thru body * = d-eoxygentated * = oxygenated Capillaries deO2 venules veins superior/inferior vena cava RT atria tricuspid RT ventricle pulmonary valve *pulmonary arteries* lungs (O2 picked up/ CO2 dropped off / diffusion) O2 blood returns to heart via *pulmonary veins* LT atrium mitral/bicuspid valve LT ventricle aorta arteries arterioles capillaries O2 dropped off CO2 picked up start again! Heartbeat 2 networks of fibers: one in atria one in ventricles when single fiber in either network stimulated network contracts as unit Each contraction begins w/ SA Node (Sinoatrial Node) Pace Maker in RT atrium Impulse spreads from SA Node network of fibers in Atria picked up by Atrioventricular Node (bundle of fibers) & carried to network of fibers in ventricles 2 step pattern of contraction makes hear pump efficient When network in atria contract blood in atria ventricles When network in ventricles contract blood in ventricles flows out of heart Heartbeat ↑ or ↓ based on O2 need Vigorous exercise need ↑ O2 for CR (ATP production) heart rate 200bpm (from 72) Controlled by Autonomic NS (Brain Stem regulates BP, HR, breathing, swallowing) Neurotransmitters released by sympathetic NS ↑ heart rate Antagonistic Neurotransmitters released by parasympathetic NS ↓ heart rate 34 CNS (brain/spinal cord) NS Somatic NS (skeletal/voluntary) Motor nerves PNS sympathetic ↑ Autonomic NS (involuntary/smooth/cardiac) Sensory nerves parasympathetic ↓ Blood Vessels O2 blood (left side of heart) leaves LT ventricle Aorta body Blood is circulatory system flows thru 3 types of blood vessels: Arteries Capillaries Veins Arteries: Lg vessels that carry blood away from heart O2 except for pulmonary artery (going to lungs to get O2) Thick walls to withstand pressure produced when heart contracts/blood pumped Connective tissue & Smooth Muscle (thicker), Endothelium smaller arterioles Capillaries: Smallest blood vessels Walls 1 cell thick for diffusion of nutrients, gases, wastes Blood cells pass single file smaller than veins venules collect into veins Veins: Returns blood to heart Connective tissue & smooth Muscle (thinner), Endothelium (like arteries) Valves (open 1 way) keep blood moving in 1 direction heart Many veins located near skeletal muscle contractions help move blood thru veins often against force of gravity Exercise prevents pooling of blood & stretching of veins If walls weaken blood pools in veins varicose veins * post mortem pool/ all muscle contractions stop 35 Capillaries: site of O2, CO2, nutrient and waste exchange Blood Heart contract produces pressure Force of blood on artery walls = BP Pressure BP ↑ when hear contracts and ↓ when hear relaxes Measure BP w/ sphygmomanometer & cuff wrapped around upper arm (Typical 120/80) Air pumped into cuff until flow thru artery is blocked As pressure is released listen to pulse w/ stethoscope (#’s w/ pressure gauge) 1st # systolic force felt in arteries when ventricles contract 2nd # diastolic force felt in arteries when ventricles relax *bad if high Body regulates BP in 2 ways Sensory receptors in body detect BP & send messages to medulla oblongata in (brain stem) BP too high Autonomic NS releases neurotransmitters smooth muscles in blood vessels to relax (↓BP) BP too low neurotransmitters smooth muscles in blood vessels to constract (↑BP) Kidneys remove/retain H2O from blood & regulate BP BP too high Hormones released cause kidneys to remove more H2O from blood reduces volume ↓BP BP too low release of kidney enzyme renin activates hormone angiotensin causes arterioles to constrict ↑BP Angiotensin also stimulates adrenal glands to release aldosterone causes kidneys to retain salt leads to ↑ H2O in blood ↑BP 36 Diseases of Circulatory System Cardiovascular Disease: heart disease & stroke leading cause of death/disability in US 2 main causes High BP & Atherosclerosis force heart to work harder High BP/Hypertension weakens/damages heart muscle & vessels ↑ incidence of heart attack/stroke Atherosclerosis plaque (fat deposits) build up on inner walls of arteries ↑BP Atherosclerosis in coronary arteries (bring nutrients,O2 to heart) MI MI symptoms: nausea, shortness or breath, severe/crushing chest pain Early detection new medications ↑ blood flow to heart if given early! Atherosclerosis in carotid arteries (brings nutrient, O2 to brain) stroke Blood clots from Atherosclerosis break free block brain vessel stroke Regular exercise heart stronger, ↑ endurance-efficiency, ↓wt & body fat, ↓ stress Balanced Diet ↓ in fats (sat) & cholesterol, ↓wt & body fat, ↓ chance of atherosclerosis Blood Circulatory System carries blood thru vessels body Blood: Connective Tissue Contains dissolved substances & specialized cells Collects O2 from lungs, nutrients from digestive tract, waste products from tissues Regulates body temp RBC’s carry O2 from lungs cells & CO2 from cells lungs WBC’s fight infection Platelets help clotting Human Body has 4-6L of blood 45% cells 55% liquid plasma liquid that suspends cells Plasma: 90% H2O 10% dissolved gases, salts, nutrients, enzymes, hormones, waste products, & plasma proteins Plasma Proteins (3 groups) Albumins & Globulins: transport fatty acids, hormones, vitamins Albumins: regulate osmotic pressure & blood volume Globulins: fight viral/bacterial infections Fibrinogen: helps in blood clotting 37 Blood Cells: Cellular portion of blood RBC’s/ Erythrocytes: 5million/ml blood Transport O2/CO2 Color from Hgb (Fe containing protein binds O2 in lungs & transports it to body cells). Biconcave disks ↑ SA carries ↑O2 produced from stem cells in red bone marrow (ends of lg bones & in flat bones) Fill w/ Hgb & lose nuclei/organelles 120 day life span (no nucleus) destroyed in liver & spleen *poikilocytosis/anisocytosis anemiasinadeq O2 carry capacity b/c of shape or RBC # WBC’s/ Leukocytes: Part of Immune System 7000/ml blood (↑ WBC = infection) Produced in red bone marrow from stem cells Nucleated (life span days, months, years) Guard vs infections (bacterial, viral, parasitic etc) 5 Types / Specific Fx: Phagocytes (Neut’s & Mono’s) engulf/digest Baso’s release chemicals (histamines) that ↑ blood flow to area redness/swelling associated w/ allergies, release anticoagulants clotting Eos attach parasites, ↓ inflammation associated w/ allergies Lymphocytes produce Ab’s (proteins that help destroy Pathogens) Help produce Immunity 38 Platelets and Blood Clotting Plts (cell fragments from red bone marrow) contact w/ broken vessel Plt surfaces become sticky cluster of Plts release clotting factors (proteins/enzymes) Chemical Rxs Thromboplastin converts Prothrombin (in plasma) Thrombin Thrombin converts Fibrinogen sticky mesh fibrin filaments Cells trapped produce clot, bleeding stops Bleeding Disorders: factors in clotting cascade deficient Hemophilia inherited genetic disorder from deficient/defective factor VIII Treatment injections of missing clotting factors The Respiratory System Respiration and Breathing Breathing mvmt of air in/out of lungs C.R. in mitochondria release Energy from break↓ of food particles (w/O2) ATP Respiration Organism Level Process of gas exchange between lungs & env. Release of CO2 from CR uptake of O2 from air Human Respiratory System Fx exchange of O2 & CO2 between Blood, Air, Tissues nose/mouth pharynx larynx trachea Lt/Rt bronchi bronchioles alveoli Air enters nose/mouth pharynx (throat) passage for food/air larynx (at top of trachea) w/ elastic folds (vocal chords) Muscles pull vocal chords together Cause chords to vibrate produce sound Trachea/windpipe (cartilage) S&F/ prevents collapse Epiglottis (flap of tissue) covers trachea entrance when food swallowed (food esophagus) Air warmed, moistened, filtered protects lung tissue for efficient gas exchange hairs line nasal cavity cells lining resp tract produce mucus trap particles cilia sweep particles & mucus away from lungs pharynx swallowed or spit put * smoking/tobacco paralyzes cilia crap gets into lungs black! Rt/Lt Bronchi branch off trachea lead to Lungs smaller bronchi Bronchioles Surrounded by smooth muscle for support & enables Autonomic NS to regulate size of passageways Alveoli clusters site of gas exchange at end of bronchioles Network of capillaries surround each Alveolus Blood w/ CO2 & air w/ O2 side by side Exchange/Diffusion O2 carried by Hemoglobin protein in RBC’s (O2 binds to Fe in Hgb molecule) 39 Site of gas exchange Blood drops off CO2 & picks up O2 Breathing Mvmt of air in/out of lungs No muscles connected to lungs Force that drives air into lungs from Air Pressure Lungs sealed in 2 sacs (pleural membranes) inside chest cavity (heart just Lt of center Lt lung 2 lobes Rt lung 3 lobes) Diaphragm muscle at bottom of chest cavity Inhale Diaphragm contracts, moves ↓, rib cage rises and ↑ volume of chest cavity Chest cavity tightly sealed, partial vacuum created inside chest cavity b/c of atmospheric pressure air rushes into breathing passages ExhalePassive event Rib cage lowers as diaphragm relaxes & moves back up ↓ volume of chest cavity Pressure in chest cavity becomes greater than atmospheric pressure Air rushes back out of lungs Ah, but…greater force needed to blow out birthday candles Muscles surrounding chest cavity provide extra force & contract as diaphragm relaxes System works b/c chest cavity is sealed. Puncture wound to chest air leaks in lose vacuum lungs collapse 40 How Breathing is Controlled Breathing voluntary but ultimately involuntary Fx Medulla Oblongata in brain stem controls breathing Autonomic Nerves from Medulla Oblongata to diaphragm & chest muscles produce cycles of contraction that bring air into lungs Cells in Medulla Oblongata’s breathing center monitor amount of CO2 in blood As blood CO2 levels ↑, nerve impulses from breathing center cause diaphragm to contract Brings air into lungs Higher blood [CO2] stronger the impulse to breathe Can’t hold your breath! Plane at high altitudes: ↓ O2 but cabin pressurized Passengers have to be told to put on O2 masks b/c body starving for O2 but CO2 levels have not ↑ causing you to breathe involuntarily! Everest climbers rest camps Polycythemic ↑ # RBC’s to ↑ O2 carrying capacity Blood Doping Tobacco and the Respiratory System Nicotine: Addictive, Stimulant drug that ↑’s heart rate & BP CO: Poisonous gas blocks transport of O2 by Hgb in RBC’s CO binds 200x’s faster than O2 at same Hgb site Deprives heart & other organs of O2 required to Fx efficiently Tar: contains # of cancer causing cmpds Nicotine & CO paralyze cilia inhaled particles stick to sides of Resp Tract smokers cough, or to lungs damage Irritation from mucus lining of Resp Tract to swell &↓ airflow to alveoli 41 Diseases Caused by Smoking Chronic Bronchitis: Bronchi swell & clogged w/ mucus Simple activities like climbing stairs becomes difficult Emphysema: Loss of elasticity in lung tissue makes breathing difficult Can’t get enough O2 in Can’t get CO2 out Lung Cancer: cells spread to other locations in body deadly Heart Disease: Smoking constricts/narrows blood vessels ↑ BP Heart works harder Smoking and the Nonsmoker 2nd hand smoke damaging to anyone who inhales it Especially young kids lungs still developing Res Digestion System Food and Nutrition Food & Energy: Food provides body w/ Energy Cells convert chemical energy stored in food ATP Energy in food can be measured by burning it converted to heat measured in calories calorie: amt of heat needed to raise 1gm H2O 10 C 1 Calorie: = 1000calories = 1 kcal Nutrients: Substances in food that supply energy (ATP) & raw materials req’d for Chemical Rx’s, growth, repair, development H2O, minerals (inorganic) carbs, fats, proteins, vitamins, (organic) ↑ Energy w/ exercise = higher Energy needs Energy needs of average sized teen/day 2200 for females/2800 for males 42 Concept Map Section 38-1 Nutrients include Carbohydrates Fats Proteins Vitamins Minerals include are made of are made using include include Simple Complex such as such as Sugars Starches Amino acids Fatty Acids Calcium Glycerol Fat-soluble Watersoluble Go to Section: H2O: Most important b/c every cell needs H2O to carry on processes & Rxs Makes up most of blood, lymph & body fluids Sweat (mostly H2O) evaporates & cools body maintains B.T & homeostasis Lost in urine & breath 1L/day req’d to prevent dehydration affects body systems Carbs: Simple (mono/disaccharides & complex (polysaccharides, starch & glycogen) C-H-O = Main source of Energy 1 :2: 1 Broken ↓ by digestive system carried thru blood to cells Glycogen stored starch in liver & skeletal muscle Cellulose/Fiber: In whole grains, fruits, veg’s Can’t be broken ↓ Bulk keeps moving food thru digestive tract Fats/Lipids: (2 or 3 fatty acids + glycerol) C-H-O “essential” fatty acids req’d for C.M’s, myelin sheaths (axon), hormones 1 : 2 : few Help body absorb fat soluble vitamins Extra calories stored as fat Protects & insulates Saturated: (solid at RT, meats) no C=H in (f.a’s) Unsaturated: 1 C=H (in f.a’s) Polyunsaturated: (liquid at RT plants) 2+ C=H (in f.a’s) Max 30% calories from fat w/ ≤ 10% saturated ↑ (sat) fat intake ↑ BP, heart disease, obesity, diabetes, etc Iron 43 Proteins: Polymers of aa’s (8 essential (meat, fish, eggs,), 12 body makes) C-H-O-N Vegetarians must eat combo of beans & rice Growth, Development & Repair Regulatory & Transport fxs Ex. Hormone Insulin protein that regulates BS Hgb protein in RBC’s carries O2 Vitamins: Organic, help regulate body processes & work w/ enzymes Most obtained from food Bacteria in digestive tract synthesize Vit K Skin exposed to light synthesizes Vit D Vitamin deficiency disease Fat soluble: A,D, E, K can be stored in fatty tissues in XS can be toxic H2O soluble: C, B can’t be stored (must have daily) Minerals: Inorganic Ex. Ca,P in bones & teeth Fe needed to make Hgb Ca, Na, K nerve & muscle fx, etc Ca, K blood clotting Not metabolized lost in sweat, urine, waste Nutrition & Balanced Diet (Research Vitamin & Mineral Deficiencies) Food Guide Pyramid: Classifies foods into 6 groups Indicates # of serving from each group Food Label: Provides nutritional info w/ Daily Values, calories 44 Figure 38–8 Food Guide Pyramid Section 38-1 Fats, Oils, and Sweets (use sparingly) Soft drinks, candy, ice cream, mayonnaise, and other foods in this group have relatively few valuable nutrients. Milk, Yogurt, and Cheese Group (2-3 Servings) Milk and other dairy products are rich in proteins, carbohydrates, vitamins, and minerals. Vegetable Group (3-5 servings) Vegetables are a low-fat source of carbohydrates, fiber, vitamins, and minerals. Meat, Poultry, Fish, Dry Beans, Eggs, and Nut Group (2-3 servings) These foods are high in protein. They also supply vitamins and minerals. Fruit Group (2-4 servings) Fruits are good sources of carbohydrates, fiber, vitamins and water. Fats Sugars Bread, Cereal, Rice and Pasta Group (6-11 servings) The foods at the base of the pyramid are rich in complex carbohydrates and also provide proteins, fiber, vitamins, and some minerals. Go to Section: The Process of Digestion Digestive System: Alimentary Canal/GI tract 1-way tube that passes thru body Open at both ends Includes: mouth, pharynx (digestive & respiratory), esophagus, stomach, sm intestine, lg intestine/colon Accessory organs: food does not pass thru Salivary glands, Pancreas, Liver (+ secretions) Fx: convert foods into simple molecules for absorbed used by body cells Mechanical Digestion: Specialized teeth grind & chew Stomach sm muscles churning Peristalsis sm muscles pushing food thru tube Chemical Digestion: enzymes break down food sm molecules absorption into blood 45 Figure 38–10 The Digestive System Section 38-2 Mouth Pharynx Salivary glands Esophagus Liver Gallbladder (behind liver) Stomach Pancreas (behind stomach) Large intestine Small intestine Rectum Go to Section: 46 The Mouth Teeth: Mechanical Specialized S&F (cutting, grinding, tearing, crushing) ↑ SA by ↓ particle size for ↑ enzyme fx efficient Protected by enamel Saliva: Secreted by (3) salivary glands (NS control Ex. smell/thought- sour patch kids) moistens food ease passage Contains amylase Begins chemical digestion of starches sugars Lysozymefights infection by digesting CW of many bacteria (on food) The Esophagus: Swallowing actions of tongue & throat push bolus ↓ Epiglottis closes off trachea prevents food block of airways Food passes from throat Esophagus Sm muscle tube (throat – stomach) Peristalsis- sm muscle wavelike contraction (lg & slow) propel food ↓ into stomach Cardiac Sphincter: sm muscle ring between esophagus & stomach Prevents contents going stomach esophagus Heatrburn: painful/burning from backflow of acid from stomach Stomach: muscular sac Continues mechanical digestion Alternating contractions of 3 sm muscle layers churns food chyme Chemical digestion: Glands in stomach lining secrete: Mucus: lubricates/protects stomach walls HCl ↓ pH activates enzyme pepsin (works best in acidic env) HCl & Pepsin protein digestion pp Acid inactivates amylase carb digestion stops until sm intestine Pyloric Valve: between stomach & sm intestine opens Chyme passes sm intestine Small Intestine: Most digestion & absorption of nutrients Duodenum (secretions from duodenum, pancreas, bile duct & liver enter ↑ chemical digestion) Jejunum Ileum 47 Accessory Structures of Digestion: (food DOES NOT pass thru) Pancreas: behind stomach 3 fxs: Produce hormones that regulate BS levels Produces enzymes that break ↓ carbs, proteins, lipids, nucleic acids Produces Na HCO3 base neutralizes stomach acid so enzymes effective (sensitive to pH) enzymes proteins can denature protects lining of sm intestine Figure 38–13 The Liver and the Pancreas Section 38-2 Liver Bile duct Gallbladder Pancreas Pancreatic duct Duodenum To rest of small intestine Go to Section: Liver: above & left of stomach Produces bile (w/ salts & lipids) stored in gal bladder under liver emulsifies fats for enzymes to work on smaller fat molecules Absorption in Small Intestine Duodenum short vs Jejunum & Ileum ~6m most absorption Vili: Folded surfaces of sm intestine (fingerlinke projections) Microvilli: off vili ↑ SA absorption of nutrients Peristalsis: moves chyme thru sm intestine Most carb & protein digestion absorbed into capillaries in vili Undigested fat & fatty acids absorbed into lymph vessels H2O, cellulose & other un-digestible materials remain lg intestine Appendix: Vestigial organ in humans inflamed appendicitis removed Other mammals use it to store cellulose & materials enzymes can’t break ↓ 48 Figure 38–14 The Small Intestine Section 38-2 Small Intestine Villus Circular folds Epithelial cells Villi Capillaries Lacteal Vein Artery Go to Section: Large Intestine (colon): shorter but wider diameter than sm intestine Ascending Chyme from sm intestine ileocecal valve lg intestine Transverse Descending Primary Function remove H2O from remaining undigested material Sigmoid Bacteria in colon produce Vit K Antibiotics can destroy (normal) bacteria Vit K deficiency Fecal material passes thru colon rectum anus Digestive System Disorders Ulcers: whole in stomach from ↑ acid Heliobacter pylori peptic ulcers Diarrhea (↓H2O absorption) & nutrient absorption b/c material moving thru too fast! Constipation (↑ H2O absorption) 38 Excretory Systems 49 Excretory Organs: Rid metabolic wastes xs salts & CO2 urea (toxic cmpd produced when aa’s used for energy Excretion: process of eliminating wastes Skin: excretes xs H2O, salts, urea, UA in form of sweat Lungs: excrete CO2 (produced from CR) Liver: takes up xs aa’s useful cmpds & produce N-wastes But then converts them to urea Urea removed by Kidneys Fx’s of Excretory System: Help maintain homeostasis & acid base balance Remove waster products from blood Maintain blood pH Regulate H2O content of blood ( so blood volume) Kidneys: Main excretory organs Located on either side of spinal column/lower back Ureter: (tube leaves each kidney & carries urine bladder) Dirty / O2 Blood: enters thru renal artery Clean / DeO2 blood exits thru renal vein Kidney Structure: 50 Renal Medulla (inner) Renal Cortex (outer) Nephrons: Functional units of kidney (>1million/kidney) In renal cortex except Loops of Henle (descend into medulla) Nephron Structure: Dirty / O2 blood enters nephron thru arteriole (sm) Wastes filtered out urine collecting duct ureter bladder (stored) urethra Clean / DeO2 blood exits nephron thru venule (lg) Figure 38–17 Structure of the Kidneys Section 38-3 Kidney Nephron Bowman’s capsule Cortex Capillaries Glomerulus Medulla Renal artery Renal vein Ureter Collecting duct Vein To the bladder Artery Loop of Henle Go to Section: Blood Purification / Urine Formation To the ureter 51 Filtration of blood in Glomerulus:sm network of capillaries Encased in Bowman’s Capsule permeable to filtrate Blood enters under pressure most materials filtered out filtrate Filtrate contains H2O, urea, glucose, salts, aa’s, vit’s Cells (RBC’s, WBC’s, plts & plasma proteins) too big to pass thru capillaries remain in blood All blood filtered every 45 minutes but most filtrate reabsorbed Reasborption: liquid/materials in filtrate that are taken back into capillaries 99% of H2O (osmosis) follows, aa’s, fats, glucose (AT) In Tubule system PCT, Loop of Henle, DCT Concentrated remains = Urine collecting duct Bladder stores urine urethra/void Secretion: opposite of reabsorption xs materials in peritubular capillaries tubules urine Drugs & Urinary System: Drugs usually remain in filtrate effects wear off Drugs (legal/illegal) concentrated in urine testing The Nephron Section 38-3 Reabsorption Filtration Most filtration occurs in the glomerulus. Blood pressure forces water, salt, glucose, amino acids, and urea into Bowman’s capsule. Proteins and blood cells are too large to cross the membrane; they remain in the blood. The fluid that enters the renal tubules is called the filtrate. As the filtrate flows through the renal tubule, most of the water and nutrients are reabsorbed into the blood. The concentrated fluid that remains is called urine. Go to Section: Control of Kidney Fx Maintained by blood composition Regulatory Hormones released in response to blood composition 52 If xs H2O, salts, etc less reabsorbed in tubules urine If deficient more reabsorbed in tubules blood Maintains: Proper blood composition Acid Base balance / pH Kidney Dialysis: Blood removed from line Pumped thru tubes that act as nephron (dialysis tubing) Wastes: urea, xs salts, etc diffuse out of blood Purified blood returned to body