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Question:1. What might the advantage of a flat, thin leaf blade be to the photosynthetic capacity of a plant? How does the arrangement of leaves on a stem relate to the photosynthetic capacity of a plant? 2. On the basis of your observations of chloroplast location in the leaf, which cells are the main photosynthetic cells? 3. How might the cuticle affect effiency of photosynthesis? 4. How does the structure of the spongy tissue differ from that of other leaf tissue? 5. What does the relationship of stomata and spongy tissue suggest about the function of spongy tissue? 6. Why might some of the stomata you observed be open? Closed? Explain. 7. If a plant's stomata close in a hot, dry day, how could this affect the plant's rate of photosynthesis? 8. More stomata are located on the lower epidermis of most leaves than on the upper epidermis. Why? 9. Grass leaves have the same number of stomata on their lower and upper epidermis. Why?

Answers:1. Reduce the distance light has to travel to reach the photosynthetic cells. Leaves are arranged in a mosaic pattern so that all can have a chance to recieve light for photosynthesis. 2. Mesophyll and pallisade cells contain the most chloroplast so are the main photosynthetic cells. 3. Thinner cuticles increases the rate fo PSS 4. Check your diagram/picture and compare it 6. Stomata opens when water builds up in the guard cell, ending it and opening the stomata. When too much water is lost, guard cell shrink and close the stomata. 7. Slows down/ decrease rate 8. More on lower to reduce water loss by transpiration. 9. What do you think???

Question:1.explain the functions of roots in a vascular plant? Roots in a vascular plant are used to store food and water. 2.explain the function of the epidermis, cortex, endodermis, pericycle, xylem, and phloem in roots? 3.identify each type of tissue in either pictures or diagrams? 4.explain how roots take in water and minerals and get them to the xylem? 5.explain the function of the root cap, meristematic region, elongation region, and maturation region? 6.explain primary growth in a root?

Answers:Primary Growth: Apical meristem is responsible for primary root and stem growth in vascular plants. Primary Root Growth: is concentrated near the tip and results in the root growing in length. The root tip contains 4 zones of development: The root cap, which protects the area behind it and softens the soil ahead of it by producing a polysaccharide. The apical meristem, is an area of rapidly dividing cells. It will replace the cells of the root cap as they wear away and push cells above them that will develop into the main tissues of the plant. The zone of elongation, is an area where the cells elongate 10 times their original length. This elongation helps push the root into the soil. The zone of maturation, is the area farthest from the root tip. Here the new cells will specialize and carry out the functions of the epidermal, ground, and vascular tissue. The primary tissues in a dicot root are arranges in a central x pattern for the xylem with the phloem located in each of the angles of the xylem. In a monocot the vascular tissues are alternated in a circle. Primary Stem Growth: begins at the tip of the terminal bud in the area called the apical meristem. The cell divisions are responsible for the stem's growth in length. The primary vascular tissue in monocots takes on a scattered arrangement. In a dicot, it takes a circular pattern. Transport in Plants: Absorption of water and minerals by roots: Water and mineral enter through root epidermis, cross the cortex, pass into the stele, and are carried upward in the xylem. Active accumulation of Mineral Ions. The cells cannot get enough mineral ions from the soil by diffusion alone. The soils solution is too dilute. ACTIVE TRANSPORT of these ions must occur. Specific carrier proteins in the plasma membrane attract and carry their specific mineral into the cell. A Proton Pump: H+ is pumped out of the cell causing a change in pH and a voltage across the membrane. This helps drive the anions and cations into the cell. Water and minerals cross the cortex in one of 2 ways: Via SYMPLAST which is the living continuum of cytoplasm connected by PLASMODESMATA. Via APOPLAST which is nonliving matrix of cell walls. At the endodermis the apoplastic route is blocked by the CASPARIAN STRIP. this is a ring of suberin around each endodermal cell. Here water and minerals MUST enter the stele through the cells of the endodermis. Water and minerals enter the stele via symplast, but xylem is part of the apoplast. Transfer cells selectively pump ions out of the symplast into the apoplast so they may enter the xylem. This action requires energy. ASCENT of XYLEM SAP: Water transported up from the roots must replace water lost by transpiration. WATER POTENTIAL: Xylem sap rises against gravity, driven by a gradient of water potential. Water flows from an area of high potential to an area of low potential. Water Potential is expressed in units of pressure: 1 bar is the pressure needed to push up a column of water 10 meters. 1 megapascal = 10 bars. Pure water has a potential of 0. Addition of pressure increases water potential. Addition of solutes decreases it. ROOT PRESSURE: When transpiration is low, ions pumped into the stele decrease water potential and cause water uptake by the stele. This uptake force is called root pressure. It Cannot keep pace with transpiration, and can only force water up a few meters. TRANSPIRATION-COHESION-ADHESION THEORY: a). water exits leaf through stomata. b). this water loss is replaced by evaporation from mesophyll cells, lowering their water potential, causing them to take water from neighboring cells. c). the process connects back to the tracheids causing water to be taken from the xylem. d).Water travels from the tracheids to the air following a water potential gradient. e). Waters cohesive and adhesive properties and the small diameter of xylem aid in its movement of up the tube. f). This pull decreases water pressure in the xylem causing the roots to take water from the soil.

Question:Can someone help me check for my answers... AACDAEEAEDEACACEDAACACBBAECBDD... 1) Under anaerobic conditions yeast release A) lactic acid.B) urea.C) ethyl alcohol. And carbon dioxide D) carbon monoxide.E) oxygen. 2) The term aerobic means A) with O2.B) wine making.C) without CO2.D) without O2.E) with CO2. 3) Respiration ____, and cellular respiration ____. A) produces glucose . . . produces glucose B) is gas exchange . . . produces ATP C) produces ATP . . . is gas exchange D) produces glucose . . . is gas exchange E) uses glucose . . . produces glucose 4) Humans use the calories they obtain from ____ as their source of energy. A) water B) sunlight C) minerals D) food E) both a and b 5) The overall equation for the cellular respiration of glucose is A) C6H12O6 + 6O2 > 6CO2 + 6H2O + energy. B) 5CO2 + 6H2O > C5H12O6 + 6O2 + energy. C) C6H12O12 + 3O2 > 6CO2 + 6H2O + energy. D) C5H12O6 + 6O2 > 5CO2 + 6H2O + energy. E) none of the above. 6) During cellular respiration, the energy in glucose A) is used to manufacture ATP by endergonic reactions. B) is released a little bit at a time. C) is released all at once. D) is released by exergonic reactions. E) a, b, and d. 7) Unlike those of eukaryotes, the electron transport chains of prokaryotes are located in/on the A) ER. B) central vacuole. C) plasma membrane. D) nuclear membrane. E) Golgi apparatus. 8) A drug is tested in the laboratory and is found to create holes in both mitochondrial membranes. Scientists suspect that the drug will be harmful because it will inhibit A) the Krebs cycle.B) chemiosmosis.C) formation of alcohol.D) glycolysis.E) both a and b. 9) Glycolysis A) does not occur in bacterial cells. B) does not occur in animal cells. C) does not occur in plant cells. D)does not occur in yeast cells E) takes place in virtually all cells. 10) Pyruvic acid is considered a(n) ____ aerobic cellular respiration. A) end product of B) enzyme in C) source of O2 for D) intermediate in E) cofactor in 11) During cellular respiration, glucose is converted into two pyruvic acid molecules. These molecules A) together contain less chemical energy than was found in the original glucose molecule. B) are each converted into a two carbon molecule joined to a coenzyme A molecule. C) are oxidized. D) each lose a carbon atom, which is released as CO2. E) all of the above. 12) The bridge between glycolysis and the Krebs cycle is A) the oxidation of FADH2.B) the conversion of pyruvic acid to acetyl CoA.C) the production of alcohol.D) the oxidation of NADH.E) the conversion of ADP to ATP. 13) The enzymes of the Krebs cycle are located in the A) cytoplasm.B) intermembrane space of the mitochondrion.C) mitochondrial matrix.D) outer mitochondrial membrane.E) inner mitochondrial membrane. 14) The end products of the Krebs cycle include all of the following except A) pyruvic acid.B) ATP.C) CO2.D) FADH2.E) NADH. 15) At the end of the Krebs cycle, most of the energy remaining from the original glucose is stored in A) FADH2.B) pyruvic acid.C) ATP.D) CO2.E) NADH. 16) In the respiratory electron transport chain, electrons are passed from one electron transport molecule to another and are finally accepted by A) ADP.B) an oxygen atom.C) a molecule of water.D) a molecule of carbon dioxide.E) ATP. 17) Each FADH2 yields a maximum of ____ ATP and each NADH yields a maximum of ____ ATP as a result of transferring pairs of electrons to the electron transport chain. A) 3 . . . 1B) 3 . . . 2C) 3 . . . 3D) 2 . . . 3E) 1 . . . 3 18) Both glycolysis and the Krebs cycle must occur ____ times per glucose molecule. A) 2B) 3C) 4D) 5E) 1 19) Bacteria that are unable to survive in the presence of oxygen are called A) strict anaerobes.B) microaerophiles.C) aerobes.D) chemosynthetic bacteria.E) facultative anaerobes. 20) Muscle soreness associated with strenuous exercise is at least partly due to A) the large amount of carbon dioxide that builds up in the muscle. B) the accumulation of alcohol from anaerobic respiration. C) the presence of lactic acid from fermentation by muscle cells. 21) When a fatty acid is used for aerobic respiration, it is converted into ____, which is fed into ____. A) glyceraldehyde 3 phosphate . . . glycolysis (partway through)B) citric acid . . . the Krebs cycleC) acetyl CoA . . . the Krebs cycleD) glucose . . . glycolysisE) pyruvic acid . . . the pyruvic acid "grooming" step 22) If you consume one gram of each of the following, which will provide the most ATP energy? A) proteinB) sucroseC) glucoseD) fat E) starch 23) The overall equation for photosynthesis is A) the same as the equation for glycolysis written in reverse. B) 6CO2 + 6H2O > C6H12O6 + 6O2. C) C5H12O6 + 6O2 > 5CO2 + 6H2O. D) C6H12O6 + 6O2 > 6CO2 + 6H2O. E) both a and d. 24) Autotrophs A) include only the green plants. B) make organic food molecules from inorganic raw materials. C) eat other organisms that use light energy to make food molecules. D) make sugar by using organic raw materials. E) both a and d. 25) Autotrophs that utilize light as their energy source are A) photosynthetic autotrophs.B) heterotrophs.C) consumers.D) fungi.E) chemosynthetic autotrophs. 26) Producers A) sustain themselves without eating.B) make organic food molecules from simple raw materials.C) manufacture the biosphere's food supply.D) are autotrophs.E) all of the above. 27) Chloroplasts contain disklike membranous sacs arranged in stacks called A) cristae.B) vacuoles.C) thylakoids.D) grana.E) stroma. 28) In the chloroplast, sugars are made in a compartment that is filled with a thick fluid called the A) thylakoid.B) stroma.C) stoma.D) mesophyll.E) matrix. 29) CO2 enters and O2 leaves a leaf via A) grana.B) stroma.C) thylakoids.D) stomata.E) central vacuoles. 30) Chloroplasts are surrounded by A) grana.B) a single membrane.C) cristae.D) a double membrane.E) thylakoids. 31) Which of the following molecules is both a reactant and a product of photosynthesis? A) glucoseB) chlorophyllC) CO2D) O2E) H2O 32) Which of the following is not a difference between photosynthesis and cellular respiration? A) Photosynthesis is ultimately powered by light energy; respiration, by the chemical energy of fuel molecules. B) Photosynthesis consumes CO2; respiration consumes O2. C) ATP is produced during respiration but not during photosynthesis. D) Photosynthesis produces O2; respiration produces CO2. E) The principal electron carrier in photosynthesis is NADPH; the principal electron carrier in respiration is NADH. 33) Why are (most) plants green? A) Green is the best color light for plant growth. B) Chlorophyll reflects green light. C) Chlorophyll absorbs green light. D) Chlorophyll primarily uses green light as the source of energy for photosynthesis. E) Carotenoids reflect green light. 34) Of the following wavelengths of light, which would you expect to be least absorbed by chlorophyll a)A) redB) greenC) yellowD) orangeE) blue 35) A packet of light energy is called a A) photon.B) wavelength.C) pigment.D) quantum.E) phaser. 36) When a pigment molecule absorbs a photon, one of its electrons A) is put into an unstable state.B) becomes excited.C) is raised from the ground state.D) gains energy.E) all of the above. 37) Photosynthetic organisms derive their carbon from A) carbon dioxide.B) carbon monoxide.C) methane.D) hydrocarbons.E) all of these, depending on environmental conditions. 38) ATP and NADPH A) production is associated with events taking place on the inner A)mitochondrial membrane. B) are inputs to the photosystems. C) play a role in glucose synthesis by plants. D) are products of the Calvin cycle. E) all of the above. 39) What type of nutrition do most fungi possess? 40) What type of nutrition do viruses possess?

Answers:Questions 1-30 (that's all the answers that were shown in the question): 1 is C (think about how beer is made) 3 is B (you were close, just reversed) 7 is C (prokaryotes don't have organelles) 8 is E (Putting holes in both membranes of the mitochondrion would allow hydrogens to leak back and forth and wouldn't allow the hydrogen ion gradient to form, thus preventing the gradient from providing the energy for ATP synthase to produce ATP. Also, it would likely disrupt the Krebs cycle as well as this occurs inside the mitochondrion) 12 is B (from you answers to 10 and 11, since you know that pyruvate is at the end of glycolysis, see the following diagram: http://www.sp.uconn.edu/~bi107vc/images/mol/krebs_cycle.gif) 15 is E (the key phrase is "at the end of the Krebs cycle" not at the end of the electron transport chain). 16 is B (ATP is not an electron acceptor of electrons from the electron transport chain, oxygen is the standard electron acceptor in eukaryotes). 22 is D (key phrase is "1 gram")

Question:an example is that the cell is surrounded by layers(interesting fact) which is like the earth surrounded by layers(connection). my science teacher told us that one so i cant use it... please help me, this is due tomorow!!

Answers:Guard cells flank the pores in a leaf. The pores are called stomata. Each stoma is surrounded by two guard cells. If the plant has a lot of water the guard cells are rigid and curved to leave the opening. If the plant wilts the guard cells become flaccid and fill in the opening. This is how living things regulate. They control how much water they release by how much water they have inside already. This is known as a feedback loop. This concept is important in how many things work whether electronics, our economy, or even how a float valve regulates water flow in the toilet tank. Here are diagrams of the valve concept. http://books.google.com/books?id=77aBY6NCIqAC&pg=PA6&lpg=PA6&dq=feedback+float+valve+toilet+tank&source=web&ots=cczbXnCgvq&sig=gQsA_6_T6t1aWXzuoDQr6i-kups&hl=en&sa=X&oi=book_result&resnum=5&ct=result http://en.wikipedia.org/wiki/Feedback