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Chemistry Research

Chemistry Research CHAPTER 32 The tallest tree is the Redwood (Sequoia sempervirens) approx 110 m The tallest Angiosperm is the Australian Eucalyptus regnans Water Uptake and transport (Fig. 32.1) = water is essential because: transport solute, cool the body, photosynthesis and Turgor pressure Osmosis- movement of H2) through a semi-impermeable membrane Osmotic potential ( o)-depend on dissolve solute: Hi concentration means more negative o. Isoosmotic-two solution with same o; Hypoosmotic- solution that has a less negative o(more +) Turgor Pressure -hydraulic pressure result from water up take, cell turgid; analog to air pressure in a tire Water Potential ( )-Overall tendency of a solution or cell to take up water from pure water solution. = o + P, P is positive and is measured in MegaPascal (MPa); loss in P means the plant will wilt. MINERAL UPTAKE = Mineral and ions transported across membranes by protein: Pumps and Ion channel & Symport = Use both Facilitated (low K outside cell) and Active transport (depend on Respiration). = Plant do not have a Na/K pump but a H pump (generate membrane potential/ gradient). = Ion transport changes Electric potential of membrane (-120mV- can be measure by electrodes) = The traffic of ions into/out of cell can be measure by Patch clamping technique.

Apoplast & Symplast = Water moves into the Stele (more – ) from the cortex (less – ) from the soil (more less – ) = Mineral move by Mass flow or diffusion/Active transport (via Membrane Protein) Apoplast-movement through cell wall and intercellular space; it is continuous Symplast- movement through the cell and b/w cell via plasmodesmata; continuous but regulated = H2O from the Apoplast stops at the Endodermis (Stele); have Casparian strips -made of suberin = Strip separate Apoplast of the cortex from the Apoplast of the stele (periclcle) = Membrane protein enable enables selective mineral uptake and uptake rate. Transfer cells -in pericycle, transport minerals from cytoplasm back into the apoplast (MP/Mit, SA, rate) TRANSPORT IN XYLEM Model 1-pumping cells stem; ruled out by Eduard Strasburger exp-use poison pitric acid; Stop in the leaf = Exp. demonstrate: (1) pumping cell not responsible for uptake (2) leaves important (3) root not involve Model 2- Capillary action ruled out because capillary action cannot support 110 m tree (40 cm) Model 3- root pressure-based on more – in xylem & less neg in root; support by guttation Guttation- the removal of H2O through the leaves under high humidity and a abundance of H2O in the soil = The Oozing of sap from a cut stem of Coleus when the top is remove; not enough = Root pressure changes, it either weaker or stronger but will not exceed 2X atm pressure Evaporation-Cohesion-Tension mechanism (Fig. 32.8) (1)Evaporation of H2O through stomata-increase tension &make wall more – o; H2O enter nearest vein (2) Removal of H2O from leaf cause pull of water below; pull is send through the whole column (3) Column is maintain by the adhesion of water to the cell wall (glass) Summary-evaporation account for xylem transport & the resulting tension cause the cohesion Dry Air-more – o than root–less neg than sap in xylem which is less neg in leaf–less than air = Minerals dissolve in sap is transported to rest of the plant body by the phloem Evaporation-Cohesion-Tension mechanism -requires tension in column or solution of the xylem = Pressure can be measure by pressure bomb; done by Per Scholander, Fig 32.9 = In vines there is no tension in xylem until the leaves are removed; some Plants loss tension at night TRANSPIRATION THROUGH THE STOMATA Transpiration- is the loss of water from shoot (leaf) by evaporation; also cools the cell = Loss is minimize by the cuticle; impermeable to CO2 Stoma- composed of specialized guard cells in the epidermis which allow passage of H2O/CO2 = In monocot it is associated with specialized epidermal cells; but mechanism is the same in dicot = Open by pumping of K into guard cells; stretching is regulated by Microfibril = Pumping also allow for Cl & other organic ion uptake; maintain electrical balance or neutrality = Increase CO2 level in spaces of leaf and – (release of ABA); blue light also reduce H pumping CAM-succulent plants-Crassulaceae-such as Kalonchoe = Have a backward stomata cycle- opens at night; leaf tissue becomes acidic (Malic/Aspartic acid = Adapted for environment devoid of water; loss of H2O occurs in cool environment. TRANSLOCATION = Occur in the Phloem- transport sugars, aa, minerals from leaf to root Model: bi-directional, up and down the stem or petioles (2) Arrest if tissue is damage by heating (3) Inhibited by compound that inhibit cellular respiration Pressure Flow Model- fig. 32.14-32.16 = Involve active transport of sugar into sieve tube at source (leaf) and removal at sink (stem/root) = Sieve tubes at source cause increase in Turgor pressure; fluid is squeeze toward the Sink ends Sieve Plates- must be unclogged: it is regulated by protein which is randomly distributed (until cut) = Sugars pass from cell to cell via symport, then into the apoplast (active); likewise into sieve tube = Apoplast selectively sort out which compound is to be translocated; Sym-Apo-Sym not universal = Sucrose is transported via secondary transport through a symport protein (H/Sugar protein) = In sink sugar are actively unloaded-maintain gradient and P in tube; Also build up sugar in seed/fruits = In some plants, Maple, sugar is stored as starch in xylem(living) of trunk/twigs; digested in spring (syrup) CHAPTER 37 Need of one versus the many Sponges- compose of group of cell in direct contact w/ environment; function independently = get nutrients from seawater; only two layers thick Multi-cellular organism- creates internal environment made of varying extracellular matrix = Cell meet need & exchange w/ internal environment (IE)function independently thereof = Allow animal to occupy various habitat; Cell become specialized and efficient due to constant internal envment = Cell become arrange in tissue system which maintain internal Environment & perform certain task = Evolution of animal physiology maintain progress of cell-tissue-organs-organ system-maintain IE. HOMEOSTASIS- maintenance of a constant composition of the IE-regardless of it continual/variable. = Enable organism to function and adapt; It is under control and regulation in response to IE/EE.

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= Control and regulation requires information-Endocrine and Nervous system. Organ & organ system- many types Organ- group of tissue compose of cell with similar structure and biological function; 4 cell types = Epithelial, connective, muscles and nervous Epithelial-sheet of cell of intestine, skin and lungs; some have secretory function = mucous, digestive enzymes and sweat; some are ciliated- Olfactory system and fallopian tubes = some involve in absorption and transport; some are stratified (skin) or single layered-GUT Connective tissue- support and to reinforce other tissue . = Cell are embedded in extracellular matrix; Include ligament and tendons; lens of the eye; surround Gut = Include the Skin contain elastrin protein but degrades with age; Bones-is a dense connective tissue = Include Adipose tissue- fat cells and the Component of blood Muscle tissue- include cells that cause movement of organs and limb; 3 types Skeletal-connects bone to bone; under Somatic NS control-responsible for behavior. Smooth muscles- found in internal organ (stomach); involve in the constriction of blood vessel Cardiac muscles -make up heart and pump blood Nervous tissue -enable animal to deal w/info; 2 basic cell type Neurons-generate electrochemical signals; response to specific stimuli; = Communicate over long distances with other neurons/muscles/secretory cell; control activity of most organ Glial cell -support function of neurons; abundant in brain NERVOUS AND ENDOCRINE SYSTEM Nervous-process info and use the info to control physiology and behavior = Brain, Spinal cord and peripheral nerves-conduct signal from sensor to CNS; CNS to effector = Sensors- eye, ears, organ of taste and smell, organ of balance and orientation, touch; pain/temp/Pressure Endocrine system -process info and control function of organs via extracellular fluid (hormones) = Ductless glands-secretes hormone in blood; pancreas secretes insulin = There is a close interaction b/w NS and ES; cell in brain produce hormone that effect ES and vice versa = Messenger of ES or Endocrine Glands travels great distance to stimulate target cells SKIN, SKELETON AND MUSCLE SYSTEM Skin- the 1st line of defense against pathogens, loss of water; It’s the largest organ = It a major sense organs-control rate of heat exchange (neurons); regulate body temperature. Skeleton system -support and protection; also an effector ; support lever system for movement.

Muscle system -include muscles under conscious (skeletal) & unconscious control & cardiac muscles REPRODUCTIVE SYSTEM Gonads- male/female reproductive organs; include the testes/ovaries; they produce gametes = include organ that deliver the organs; uterus-support the embryo = Mammary glands-provides nutrient for infants(breast); Gonads- contain hormone producing tissues. DIGESTIVE SYSTEM -extend from mouth to anus. = It’s a continuous tubular structure–include the Gut; Gut is divided in different segment so differ function = Involve in digestion of food and absorption of nutrients; Glands-deliver digestive enzyme to the Gut = The lower Gut (intestine) reabsorb H2O from waste; Stores waste and eliminate them. GAS EXCHANGE SYSTEM -Trachea, Larynx, diaphragm = Also called respiratory system–provide O2 and eliminate CO2 = Lung- consist of many airways leading to membranous sac with large SA; the alveoli = Diaphragm is a muscle and delivers air into and out of lungs CIRCULATORY SYSTEM = Transport O2 from lungs to rest of body and CO2 from tissue to the lungs = Transport nutrients from gut, deliver waste (N2 ) to excretory system; regulate by hormones & remove heat Blood contain a liquid medium the Plasma-is continuous with the extracellular fluids LYMPHATIC SYSTEM = Consist of vesicles extending through the body; do not include the heart and is not a circulatory system = Provide the extracellular fluid to circulatory system; include the immune system = Contain specialized blood cell produce in the spleen, lymphatic nodes, thymus and bone marrow EXCRETORY SYSTEM Urine-contain salt and waste product from catabolism of Amino acids and NA = Include the Kidney-control water content of body and correct salt composition of extracellular fluid =Bladder- storage of urine; Ureter- tube b/w kidney & bladder; Urethra-opening that release urine; = Skin- excrete H2O and salt. Excretory system: also include the end of the digestive tract CONTROL OF REGULATION Homeostasis- depend on control/regulation of organs; organ system- depend on the need of cell of body Control-implies change in rate of a process; Regulation-a physiological concept-refer to maintain to a certain limit Regulation- requires the ability to obtain and use information. = Physiological regulation requires feedback from control system = AND how the information is obtain, process, integrate & converted by the regulatory system.

To analyze a regulatory system requires US to identify the source of feedback. TEMPERATURE ANALOGY Thermostat-heating-cooling system is a regulatory system; furnace/ air condition is the control system Sensors- provide the negative feedback; positive feedback amplifies an already existing response (ethylene) Feed forward information- changes the set point; it adds a clock TEMPERATURE AND LIFE = All living cell function between – 0 C and 45 C; = Chemical reaction are temperature sensitive; measure in terms of Q10 =RT/ RT-10;Q10 =1 not sensitive = Q10 can be measure for single reaction or complex physiological process (O2 consumption) = Biological process is between 2 to 3; Temperature change can be detrimental to animal ANIMAL SENSITIVITY = Some animal BT is coupled to it external temperature. Acclimalization- a physiological& biological change that animal undergo in response to seasonal change in climate = Fish-temp difference is always higher if remove from pond to lab and then to pond Metabolic compensation-readjustment of biochemical mechanism to counter effect of temp due to Acclimalization = It is not sensitive to seasonal changes but to short term fluctuation (lysozymes-diff temp same function) MAINTAINING OPTIMAL BT Homeotherms-animal that regulates Bt at constant levels Poikiltherms-animals whose temperature changes Heterotherms-Animal that regulates it’s BT at constant level some of the time Ectotherms-depend on external source of heat to maintain BT above ET Endotherms-regulate BT by producing heat metabolically or by metabolizing active mechanism of heat loss ENDODERMS VS ECTODERMS = Ectoderms cannot regulates it BT independently of it environment; BT will not drop below ambient temp = Endotherms regulates it Bt by altering it’s rate of metabolic heat loss = Endotherms also have behavioral themoregulation; Ex. Nest construction/huddling; widespread in Animals = Both can alter their rate of heat exchange b/w blood and environment-control the flow of blood to skin Ex, Iguana of Galopagus- control BT by blood flow to skin; slower heart rate; these are adaptive process. = Some Ectoderms must maintain a certain temp at specific parts of it body (flight muscle, beetles, honeybee, shark) THERMOREGUALTION IN ENDOTHERMS -Fig 37.13b, 37.14 Thermoneutral zone -narrow range of temp in which metabolic rate of Endotherms is temp independent Basal metabolic rate- is temp of metabolic rate of an animal resting in a thermoneutral zone ( no digestion/reprod) = 6X the rate of an Ectotherms of same size; Endotherms have leaker cells-expend E for Na/K-increase rate Thermoneutral zone Low zone-high rate to maintain BT due to heat loss; At maximum rate BT decline (dies).

At high extreme-expand heat to cool the body (pants/sweat); at maximum rate/High temp- BT increases (dies) Methods- mammals-either shiver or sweat; birds-shiver (skeletal muscle ATP–heat) = Brown fats–Non-shiveri …

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