Chemistry Research Essay, Research Paper
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.
= 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-shivering; use tissue rich in Mit/blood supply and Thermogenin.
COLD vs HOT- Fig. 37.21
THERMAL INSULATION AND RATE OF HEAT LOSS
= Thermal energy is release by body to it’s environment
= Muscle contraction or change blood flow to skin; WOLF-constrict Blood vessel in its feet at above 0 C
= Elephant, Rhinos, water Buffaloes have thick layer of fur; so they wallow in water
= Sweating, panting are last resort use bu animals in hot climate or habitat (H2O evaporate quickly)
THE VERTEBRATE THERMOSTAT- Fig 37.22/37.23
= All animals that thermoregulate must have a regulatory system; Info get from Hypothalamus-integration center
In Humans: If glands is cool BT rises (constriction of Blood vessels and increase rate); Hypo temp is – feedback
= Amount of increase in heat is proportional to how much the glands is cooled below the Set point.
= Hypothalamus receive info from sensor in skin to shift the set point for responses; Higher when skin is cold
FEVER
Fever is a rise in BT in response to substance called Pyrogens; heat production above set point cause chills, shiver
= Macrophages attack antigen then secretes interleukins; Interleukin stimulate prostaglandin and raise the set point
ANIMAL AND THEIR THERMOSTAT
Hypothermia- condition in which BT is below normal (starvation, illness, anesthetic)
= Can cause unconsciousness, weaker contraction, nerve impulse, slow metabolism, cell damage/O2)
Torpor-condition in which an animal lowers its BT during the time of inactivity (Air temp, mice, hummingbird)
= Willow tit lowers it Bt at night; the brain of the willow is it’s integrated center for the thermostat.
Hibernation -is the hyptherming to low temp for days of weeks;
= It assures maximum energy conservation; BT is maintain at freezing pt.
= Metabolic rate 1/5 basal (Ex bats, bears, squirrel, poor will); occur when temp is low and food scarce
= Control by biological clock(Circannual rhythm); rhythm cycle of squirrel include active season; Hib-spring to fall
Active season -Animal breed, raise young, prepare nest, fatten bodies and store food
Hibernation season -occur in bouts; lose body weight; at end sex organs become functional
CHAPTER 44
MUSCLE CONTRACTION: Actin/myosin interaction
Effectors-adaptation in response to info that is sensed, integrated & transmitted by its neuron & endocrine