Student misconceptions about plant transport a Sri Lankan example

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1 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, 2015, Student misoneptions aout plant transport a Sri Lankan example P.R.K.A. Vitharana Department of Eduation, University of Peradeniya, Kandy, Sri Lanka. For orrespondene: pushpa.vitharana@yahoo.om Astrat Students ring with them their own misoneptions to the siene lasses and it eomes a arrier in developing new onepts. Therefore, identifying misoneptions is an essential omponent in teahing siene. The ojetive of this study was to identify 10 th grade students misoneptions on plant transport with the use of twotier diagnosti test. The development proedure of the twotier diagnosti test had three steps; (i) defining the ontent oundaries of the test (ii) olleting information on student misoneptions and (iii) instrument development. Student alternative oneptions were olleted after interviewing 25 students and multiple hoie questions with free responses eing administered to the students. With the use of the date otained, sixteen (08) twotier multiple test items were onstruted. The first tier examined the ontent knowledge and the seond tier the reasons for the ontent. The oneptual knowledge examined in the test items were water asorption, mineral salt asorption, transportation of water, transpiration, organi food transportation. The diagnosti test was administered to 180, 10 th grade students. It was revealed that students possessed 18 misoneptions. The highest numer of misoneptions was reorded in the areas of organi food transportation and the transpiration. The most ommon misoneption was found in the area of organi food transportation. Keywords: Misoneptions; Twotier test; Plant transport Introdution Learning is a omplex proess in whih a learner onstruts new knowledge. Aording to Benow and Maly (2002) learners minds are not simply empty spaes waiting to e filled sine they ring their prior learning to that moment. As they further explain this is more ruial in learning siene eause of the omplex nature of ideas and onepts. Duit and Treagust (2003) emphasize that, majority of students ome to siene lasses with a knowledge or eliefs aout the phenomena to e taught and many students develop only a limited understanding of siene onepts after instrution. As Treagust (1995) further explains students onstrut understanding of phenomena and onepts as seen through their own eyes that do not math with the sientifially aepted views. Researhes onduted in Siene Eduation have demonstrated that students possess their own oneptions of natural phenomena (Treagust, 1995; Osorne, 1985; Skamp. 1998). Student oneptions that are different from sientists have een given numerous terms as misoneptions (Odom and Barrow, 1995) preoneptions, alternative framework, hildren s siene (Treagust, 1995) preoneived notions, naïve theories (Anderson, and smith, 1985) and informal ideas (Benow and Maly, 2002). Numerous researh studies have reported students alternative oneptions on a range of siene onepts e. g. eletri urrent and animals (Osorne, 1985) qualitative analysis (Tan, et al., 2002) photosynthesis and respiration (Treagust and Haslam, 1986) plant transports and human irulation (Wang, 2004) diffusion and osmosis (Odom and Barrow,1995).

2 276 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, 2015 Researhers in the field of siene eduation state that students misoneptions are strongly held and are resistant to hange (Driver,1983;Yip, 1998; Treagust, 1995; Tekkaya, 2003). When students possess misoneptions at any level, the teahers role is ruial as it is needed to eliminate misoneptions of students. Otherwise, the students would eome alien to them eing unale to assimilate new knowledge into their existing level. Therefore, teahers need to know ideas of sientists aout the onepts to e taught as well as the misoneptions of students in order to promote effetive siene teahing. The importane of identifying misoneptions has een emphasized on many oasions in literature. Aording to Osorne (1985), Staver (2007), Selley (1999) and Ross et al., (2000), it is ruial in siene teahing to identify misoneptions or alternative oneptions of students. Yip (1998) explains identifying misoneptions as an initial step in siene teahing. The role of siene teaher is to find out student misoneptions and guide them towards etter understanding through handson ativities, investigation and interation with peers and adults. Investigating hildren s ideas is important for students and teahers (Ross et al., 2000; Duit et al.,1996). It helps teahers to understand existing levels of students and allows the students to ompare existing ideas with new ones. Twotier test as a diagnosti instrument has een widely used to identify student misoneptions on iologial siene onepts (Treagust and Haslam, 1987; Wang, 2004; Odom and Barrow, 1995). Naturalisti Settings ( Duit et al., 1996; Ollerenshaw and Rithie, 1993; Tuysuz, 2004), interviews (Tregust et al., 1996; Bell, 1995; Ross et al., 2000), onept maps ( Duit et al., 1996; Toysuz, 2009; Selley, 1999; Harlen, 1992), diagnosti test items (Treagust and Haslam,1986; Wang,2004; Odom and Barrow, 1995; Tan, et al., 2002), whole lass and group disussions, (Ollerenshaw and Rithie, 1993) students drawing, writing and annotations (Ross et al., 2000; Harlen,1992)have een reported as methods to identify student misoneptions in learning siene. However none of the researh has een onduted in Sri Lanka with the use of twotier diagnosti test to identify student misoneptions. Treagust (1995) desries two tiertest as an instrument having items with two tiers to diagnose student understanding in a partiular ontent area of siene. As he further explains, the first part of eah item on the instrument is a multiple hoie ontent question with usually two or three hoies. The seond part of eah item ontains a set of four possile reasons for the answer given to the first part onsisting of the orret answer together with inorret oneptions. The ojetive of this study was to identify 10 th grade students misoneptions on Plant Transport with the use of a twotier diagnosti test. Method The study onsisted of two main phases; onstruting the twotier test and implementing the test. The design of the diagnosti instrument was ased on the proedure desried y Treagust (1995) that inluded three road phases: (a) defining the ontent in terms of propositional knowledge statements and onept map for the speified onept () otaining information aout students oneptions and () developing a diagnosti instrument. In the twotier diagnosti instrument, the first tier of eah item in the test is a multiple hoie ontent question providing several distraters along with the orret answer, The seond tier is omposed of a multiple hoie set of reasons for the answer to the first tier. The reasons provided for students ontain the orret answer and possile misoneptions identified in questionnaires and interviews. Defining the ontent 18 propositional knowledge statements given elow were identified y reviewing the grade 10 siene syllaus, teaher instrutional manual and text ooks. A onept map for plant transport system was developed (Figure 1) aording to the ontent of grade ten syllaus. Propositional knowledge

3 European Journal of Siene and Mathematis Eduation Vol. 3, No. 2, statements were ontent validated y three experiened siene graduate teahers. Disrepanies identified in the test items were orreted and modified. 1. Plants asor water through root hair ells. 2. Water inside the root hair ells has muh higher solute onentration than that in the soil. 3. Water moves into the root hair ells y osmosis. 4. Ative transport is the movement of partiles from ells to the outside or outside to the ells against onentration gradient. 5. Ative transport ours with the help of energy released due to metaoli ativities. 6. Mineral irons atively transport through root hairs. 7. Water and mineral salts are asored through root hair and transport to various parts of the plant through xylem. 8. The water moleules are strongly attrated to eah other. This is alled ohesion 9. Cohesion ours as a result of attration etween water moleules and the wall of the vessel. 10. The pressure exerted y the root system of a plant to move water up in the xylem vessels is alled root pressure. 11. Transpiration is the loss of water vapour from the aerial parts of the plant. And it mainly ours through stomata. 12. The evaporation of water from the top of the plant reates a pulling fore drawing the water up the xylem and it is alled transpiration pull. 13. Light, temperature, wind and humidity affet rate of transpiration. 14. The rate of transpiration is inversely proportional to humidity and it is diretly proportional to light, temperature and wind 15. The food made y leaves transports to all the parts of the plants through phloem. 16. The movement of food an e upward as well as downward depending upon the needs of a plant. 17. The movement of food through phloem ours due to mass flow 18. Mass flow is the movement of materials as a ulk from one plae to another due to pressure hange.

4 278 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, 2015 Figure 1. Conept map of plant transport Otaining information aout students oneptions The findings of the researh onduted y Odom and Borrow (1995) to identify misoneptions of Osmosis and Diffusion and the researh onduted y Wang (2004) to identify misoneptions of Plant transport and Human irulation were examined in onstruting multiple hoie items. In the next step of the researh unstrutured interviews were onduted with 25 grade 10 students in order to gain a road perspetive of students understanding of plant transport. All the interviews were audiotape reorded and interview transripts were prepared for eah interview. Examples of openended questions used in interviews are, How does a plant otain water? A list of students misoneptions were prepared y examining interview transripts. The next step whih I followed was developing multiple hoie items with free responses. Eah multiple hoie item was ased on limited numer of propositional knowledge statements. Multiple hoie items were designed to address students oneptions and misoneptions enountered in the literature and the interview. Eah item was followed y a spae for the student to omplete the reason why partiular option of the multiple hoies was seleted. Openended multiple hoie test instrument was administered to 25 students and the free responses were examined to ollet misoneptions of plant transport. Constrution of TwoTier diagnosti instrument Based on the olleted group of misoneptions otained from eah item in the multiple hoie test with free responses and interviews a twotier diagnosti instrument was onstruted. Eah test item in the instrument onsisted of a stem followed y twotier questions. The first tier of eah item

5 European Journal of Siene and Mathematis Eduation Vol. 3, No. 2, provided a seletion of possile distrations related to the students misoneptions in addition to the orret answer. The seond tier onsisted of four possile reasons for the first tier: three alternative reasons and one sientifially aepted reason. A pilot study was onduted to refine the item on the diagnosti text. The final version of the test onsisted of 08 items. The ontent area addressed y eah question and the relevant propositional statement is given in Tale 1. Tale 1. The ontent area and the relevant propositional statement in eah of the test item Item Numer Topi Area Water asorption Mineral salt asorption Transportation of water Transportation of water Transpiration Transpiration Organi food transportation Organi food transportation Propositional statement 1, 2, 3 4, 5, 6, 7 8, 9, 10 10, , 14 15, 16 17, 18 Sample of population The plant transport diagnosti test was administered to 180 grade ten students after instrution. The onveniene sampling was used in this researh and total numer of 6 shools three from Kandy distrit and three from Kegalle distrit were seleted. Soring the items and analysis of responses An item was sored as orret on the twotier diagnosti test when oth the tiers (ontent and reason) were seleted, and students were offered two marks for eah item. As there were 08 items students were given marks out of 16 for the whole test. Perentage of students seleting eah response omination was alulated in all 08 items as an example shown elow. (Tale 2) Tale 2. Perentage of students responses to item no.1 Item Content Reason hoie Total hoie a d No reason (1) a * * the orret ontent hoie and reason response Question No. 1 was (1a). The proess responsile for asorption of water y root hair of plants is a. Osmosis. Ative transport. Diffusion (1) The reason for my answer is eause

6 280 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, 2015 a. Conentration of ell sap is lower than that of soil water. Conentration of ell sap is higher than that of soil water. Movement of water moleules spending energy, opposing to diffusion d. Water onentration of soil partiles is lower than water onentration of root hair ell. Results and disussion The harateristis of Plant Transport System Diagnosti Test (Annex 01) summarizes in Tale 3. Tale 3. Charateristis of the Plant Transport and Human Cirulatory System diagnostis test Areas evaluated : Water asorption: item,1 Mineral salt asorption: item 2 Transportation of water: items 3, 4 Transpiration: items 5, 6 Organi food transportation: item 7, 8 Content ased on: Validated propositional knowledge statements and onept map Numer of items: 06 Reommended grade level: 10 th grade (Grade 10) Time to omplete test: minutes Perentage of students with orret ontent hoie and omination: ontent and reason are given in Tale 4. Tale 4 Perentage of students seleting the orret ontent and omination Item Content Choie Comination The range of orret answers for the first tier varied from 42.2% to 82.2% where as omination varied from 14.4% to 59.4 %. When the firsttier of the items only is taken into onsideration the results show that there is generally high perentage of orret response hoie exeeding 50% exept in two items; item 1 and 3. However when students reasoning for their hoie (omination hoie of Tale 4) in the firsttier of the item is taken into onsideration, the perentage of orret responses are muh lower in most of the items.. The highest perentage of orret ontent hoie was reorded from items no. 5 whih was ased on transpiration. The lowest perentage of orret ontent was shown in item no. 3 ased on uptake of water y roots. There is a onsiderale differene in the perentages of orret ontent hoie and the omination hoie. Eighteen major misoneptions were identified through analysis of items on the Plant transport diagnosti test (Tale 5)

7 European Journal of Siene and Mathematis Eduation Vol. 3, No. 2, Tale 5. Student misoneptions of plant transport and human irulatory system identified y the two tiered test Item Area Misoneption Identified Perentage (1) Water The movement of water to the root hair ells our due 2 asorption to osmosis sine solute onentration in the fluid inside root hair ells is lesser than in the fluid outside (soil) (2) Mineral salt Asorption of mineral irons in plants our due to 22.7 asorption onentration gradient Asorption of mineral irons take plae through permeale memranes 1 Asorption of mineral irons our due to osmosis sine it is to aording to onentration gradient 9.4 (3) Transportation of water A ontinuous water olumn maintains in xylem vessels in a tall plant due to the fore exerted y root system A ontinuous water olumn maintains in the xylem vessels due to lose of water vapor from plants (4) Transportation of water Transportation of water through xylem vessels to leaves of a tall plant our due to transpiration pull sine it loses water from leaves and filling vaant plaes 28.8 Transportation of water to the leaves of a tall plant through xylem vessels ours due to ontinuous upward pressure exreted y roots (5) Transpiration A person under a large tree in a sunny day feels ool due to transpiration sine water vapor releases from different parts of the plant Transpiration is loss of water vapor from different parts of a plant (6) Transpiration Rate of Transpiration is greater when the humidity is higher sine temperature inrease in the environment When the humidity in the environment is higher the amount of water vapor in the air eomes limited Rate of transpiration is slower when the humidity is higher sine temperature derease in the environment (7) Organi food transportation Plants otain organi food y root hairs and transport all parts of plants Food storage in plants takes plae only in the upper parts of plants (8) Organi food transportation The movement of food in phloem tissues takes plae due to onentration gradient 8.3

8 282 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, 2015 Mass flow ours due to the movement of materials to same diretion as a result of gravitational fore Mass flow is the movement of partiles to same diretion due to pressure hanges As shown in Tale 5 students had misoneptions related to eah item of the diagnosti test. The first two questions were ased on asorption of water and mineral irons. In onsidering the first question, although students seleted osmosis as the orret ontent hoie, 2% of them had misoneption regarding the solute onentration in the ells of root hairs. Students had several misoneptions in understanding movement of mineral irons. A onsiderale perentage of students 2% and 32.7% showed misoneptions in question no 3 whih was ased on transportation of water through xylem vessels. They were in the view that root system provides an enough fore to maintain a ontinuous water olumn. The next two questions were ased on transpiration. More than 10% of students showed eah misoneption in the proess of transpiration. The most ommon misoneptions were identified from the su areas organi food transportation and transportation of water. Out of those 35.5% students had misoneption in otaining organi food. Asorption of water and Minerals Item 1 and 2 examined students understanding of water and mineral asorption respetively. Responses of eah item were analyzed as shown in Tale 6. Tale 6. Perentage of students responses to item no.1 and 2 Item Content hoie (1) a (2) a d Reason hoie a d No reason * * Total *the orret hoie and reason response No response in this ategory Four major misoneptions were identified from these two items. Out of these four misoneptions three were related to mineral salt asorption. Aording to the perentage of reason hoie, it was lear that reasonale perentage of students had misoneptions regarding solute onentration of root hair ells. Nearly fifty perent of students (48.3%) have understood osmosis as the mehanism of water asorption while 34.4 and 17.1 responded ative transport and diffusion as the orret ontent hoie. During interview with students, they provided all three mehanisms osmosis, ative transport and diffusion ut most of the students were not onfident in explaining mehanism. When the first part of the item only is taken into onsideration in item 2 the results show that more than 15%

9 European Journal of Siene and Mathematis Eduation Vol. 3, No. 2, students (16.5%) in the view that osmosis as the mehanism of mineral salt asorption and 28.6% mass flow as the mehanism. Transportation of water This onept was assessed through items 3 and 4. Analyses of responses for these two are shows in Tale 7. Tale 7. Perentage of students responses to item no.3 and 4 Item Content Reason hoie Total hoie a d No reason (3) a * (4) a * *the orret hoie and reason response No response in this ategory Three misoneptions were identified from these two items. Nearly 60% of students were unaware of the role of adhesion and ohesion fores of water to maintain ontinuous water olumn. A onsiderale numer of students were in the view that transpiration only ontriute to maintain ontinuous water olumn in xylem vessels. Question no. 4 was addressed to asertain students understanding on transpiration pull. Although high perentage of them (67.2%) seleted orret ontent hoie they were inapale of seleting orret reason. Although students responded root pressure as the orret ontent ut it is only for shorter plants. Students have not paid their attention on the word higher in the stem of question. However students those who seleted root pressure without onsidering higher plants were unale to respond the orret reason. Transpiration Transpiration onept was examined through items 5 and 6. The result of the students responses to these questions are given in Tale 8. Tale 8. Perentage of students responses item no.5 and 6 Item Content hoie (5) a (6) a * *the orret hoie and reason response - No response in this ategory Reason hoie a d No reason * Total In onsidering item no. 5, 81.6% students seleted the orret ontent hoie however more than 10% of students (13.9) responded reason hoie as releases of water vapor from different parts of the

10 284 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, 2015 plant. They have not understood transpiration as the loss of water vapor from aerial parts of plants. Item no. 6 was hange of rate of transpiration when the humidity of the environment inreases. The desired response omination was Rate of transpiration dereases eause the amount of water vapor inreases in the environment A minority of students (28%) seleted the desired answer omination. The most ommon misoneption was rate of transpiration dereases when the humidity inreases eause temperature of the environment derease with inreasing humidity Transportation of organi food Item 7 and 8 examined students understanding of route of organi food. The analysis of students responses to these two questions are given in Tale 9. Tale 9. Perentage of students responses item no. 7 and 8 Item Content hoie 7 a 8 a Reason hoie a d No reason * * Total *the orret hoie and reason response No response in this ategory In item 7 the diretion of the water transport was addressed. The most ommon misoneption was the Movement of food only to upward eause organi food otains through root hairs of a plant (18.8%). Out of the students seleted orret ontent hoie 15% were in the view that food storage of plants our that upper and lower parts of plants. A total of 35.5% of students had the misoneption Plants asor organi food through root hairs and transport to different parts of plants students may have misunderstood this as the water and mineral salt asorption from food the soil. Item 8 was ased on the mehanism required for food transportation through phloem. More than 80% of students (82.2%) seleted the desired ontent hoie mass flow however only 32.8% of students seleted the orret reason. Conlusions This study provides evidene that grade ten students have several misoneptions of plant transport. The results show that high perentages of students are apale of seleting only the orret ontent hoie not the omination (ontent and reason). It is evident that students learn the ontent without understanding onepts in plant transport. The analysis of students responses reveals that students do not have a orret oneptual understanding of mehanisms responsile for plant transport espeially osmosis, diffusion, ative transport and transpiration. The results of the study were supported y other studies in the literature (Odom an Barrow, 1995 and Wang, 2004) The results of the study showed that the twotier diagnosti test was on effetive instrument for assessing students understanding and for diagnosing students misoneptions. Literature review supported the results (Treagust and Haslam, 1986, Chen et al., 2002 ; Tuysuz, 2009; Chen and Lin,2002).

11 European Journal of Siene and Mathematis Eduation Vol. 3, No. 2, Impliation for teahing Teahers need to identify students misoneptions of any siene topi in the teahing learning proess. The understanding of misoneptions is essential to develop strategies to avoid misoneptions of and promote aurate oneptual understanding of onepts and phenomena. Aknowledgements The study was finanially supported y the University of Peradeniya, Sri Lanka. Referenes Anderson, C.W. & Smith, E.L. (1985). In The eduator s handook: A researh Perspetive. Teahing Siene, Koehler, V. (ed). New York: Longman. Bell, B. (1995). Interviewing : A tehnique for assessing siene knowledge. Glynn, S. M. & Duit, R. (eds). New Jersey: Lawrene Erlaum Assoiates Pulishers. Benow, A. & Maly, C. (2002). Siene eduation for elementary teahers. USA: Wadsworth Thomson Learning. Driver, R. (1983 ) The pupil as sientist, Philadelphia: Open University press. Duit, R., Treagust, D. F. & Mansifield, H. (1996). Investigating students understanding as a prerequisite to improving teahing and learning in siene and mathematis. In Improving teahing and learning in siene and mathematis. Treagust, D. F., Duit, R. &fraser, B. J. (eds). New York: Teahers College Press. Duit, R. and Treaguat, D. F. (2003). Coneptual hange: a powerful framework for improving siene teahing and learning, International Journal of Siene eduation, 25(6), Harlen, W. (1992). The teahing of siene, London: David Fulton pulishers. Odom, A. L. & Barrow, L.H. (1995). Development and appliation of a twotier diagnosti test measuring ollege iology students understanding of diffusion and osmosis after a ourse of instrution. Journal of Researh in Siene Teahing, Vol. 32, No.1, 4561 Ollerenshaw, C. & Rithie, R. (1993). Primary siene making it work, London: David Fulton Pulishers. Osorne, R. (1985). Children s own onepts. In Primary siene: Taking the plunge. W. Harlen. (ed). Pp London: Heinemann Eduational. Ross, K., Lakin, L. & Callaghan, P. (2000). Teahing seondary siene, London: David Fulton Pulishers. Selley, N. J. (1999). The art of onstrutivist teahing in the primary shool, Great Britain: David Fulton Pulishers. Skamp, K. (1998). Ed. Teahing primary siene onstrutively, In Teahing primary siene onstrutively. 2 nd ed. Pp.143. Australia: Harourt Australia Ply Ltd. Staver, J. R. (2007). Teahing siene, Frane: International Bureau of Eduation Tan, K.C.D., Goh, N.K., Chia, L.S., treagust, D.F. (2002). Development and appliation of a twotier multiple hoie diagnosti instrument to assess high shool students understanding of inorgani hemistry qualitative analysis. Journal of Researh in Siene Teahing, Vol. 39, No.4, Tekkaya, C. (2003). Changing students sientifi misoneptions. Researh in Siene and Tehnologial Eduation, Vol. 21, No. 1, 516. Treagust, D.F. & Haslam, F. (1986). Evaluating seondary students misoneptions of photosynthesis and respiration in plants using a twotier diagnosti instrument. Paper presented at the 59 th annual meeting of the National Assoiation for researh in Siene teahing, San Franiso, California, Marh 2831, Treagust, D. F. (1995). Diagnosti assessment of students siene knowledge. In Learning siene in the shools. Glynn, S. M. & Duit, R. (eds). New Jersey: Lawrene Erlaum Assoiates Pulishers. Tüysüz, C. (2009). Development of twotier diagnosti instrument and assess students understanding in hemistry. Sientifi Researh and Essay Vol. 4(6), Wang, J. (2004) Development and validation of a twotier instrument to examine understanding of internal transport in plants and the human irulatory system International Journal of Siene and Mathematis Eduation, Vol 2, No,, Yip, D. (1998). Identifiation of misoneptions in novie iology teahers and remedial strategies for improving iology teahing. International Journal of Siene Eduation, Vol.20,No.4,

12 286 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, 2015 Annex 01 Plant Transport Diagnosti Test Instrution: This test onsists of 08 pairs of questions that examine your knowledge of Plant Transport Eah question has two parts: a multiple hoie response followed y a multiple hoie reason. On the answer sheet provided, please irle one answer from oth response and reason setions of eah question. (1) a. The proess responsile for asorption of water y root hair of plants is : a. Osmosis. Ative transport. Diffusion. The reason for my answer is eause : a. Conentration of ell sap is lower than that of soil water. Conentration of ell sap is higher than that of soil water. Movement of water moleules spending energy, opposing to diffusion d. Water onentration of soil partiles is lower than that of root hair ells (2) a. Mineral salt is essential for growth of a plant. The proess responsile for asorption of mineral salt is : a. Mass flow. Diffusion. Ative transport d. Osmosis. The reason for my answer is eause : a. Asorption ours due to onentration gradient. Asorption ours with the help of energy opposing to diffusion. Movement as a ulk due to pressure hanges d. Asorption through permeale memranes (3) a. The harateristis of water moleules to maintain a ontinuous olumn of water is : a. Root pressure. Transpiration. Cohesion Addison d. Fores. The reason for my answer is eause : a. Releasing water as water vapors. A pressure exreted y root through root system. Releasing water from tips of leaves as liquid d. Interation among water moleules and adsorption of water moleules to walls of xylem vessels (4) a. Whih one of the following proess is responsile for arrying water to the leaves of a tall plant through xylem vessels : a. Transpiration pull. Root pressure. Asorption through roots

13 European Journal of Siene and Mathematis Eduation Vol. 3, No. 2, The reason for my answer is : a. Due to a fore of moving water upward through xylem vessels. Defiieny of water in the xylem. Due to a upward pressure exerted y roots d. Removal of water from the leaves and fill that defiieny (5) a. A person under a large tree feels old. What is the responsile for this : a. Transpiration. Guttation. Transpiration and guttation. The reason for my answer is : a. Colletion of water in the environment due to removal of water as liquid form. Removal of water vapors due to sunlight from different aerial parts of a plant. Removal of water from the plant and adding to the environment d. Adding water moleules to the environment due to removal of water vapors from the leaves (6) a. When the humidity inreases transpiration rate : a. Inreases. Dereases. The reason for my answer is : a. Beause it inreases the water vapor in the environment. Beause it limits the amount of water vapour in the environment. Temperature of the environment inreases when the humidity inreases d. Temperature of the environment dereases when the humidity inreases (7) a. Organi food transportation ours in plants : a. Only to upward. Only to downward. upward and downward. The reason for my answer is : a. Movement of organi food produed in the leaves to all parts of a plant. Deposition of food in the upper and lower parts of a plant. Asorption of organi food through root hair and transportation to all parts d. Deposition of food in the upper parts (8) a. Whih one of the following phenomena is responsile for transportation of food through phloem tissue : a. Mass flow. Diffusion. Osmosis. The reason for my answer is : a. Movement of partiles for higher onentration to lower onentration

14 288 European Journal of Siene and Mathematis Eduation Vol. 3, No. 3, Movement of partiles of a material to one diretion due to gravity. Movement of partiles of a material to diretion due to pressure gradient d. Movement of materials as a ulk due to pressure gradient