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Right choice is (c) Oozing out of liquid from pores and wounds

To explain I would say: Exudation is the coming out of liquid substances from pores and wounds. Guttation is the coming out of XYLEM sap from tips of leaves. Transpiration is the loss of water from LIVING AERIAL tissue in form of VAPORS. Movement of substances through vascular bundles is known as translocation.

Correct choice is (a) Pressure flow HYPOTHESIS

Easy explanation: Pressure flow hypothesis is the most accepted MECHANISM for the translocation of sugars from source to sink. Cohesion-tension theory EXPLAINS the PROCESS of transpiration. Root pressure theory demonstrates the movement of xylem sap. Imbibition is the reason behind emergence of seedlings out of the soil.

Correct answer is (d) greater kinetic energy

For explanation: Increase in concentration of water in a system LEADS to increase in K.E and thereby the water potential of the PLANT. It REDUCES hypertonic solution and aim to achieve isotonic condition. It decreases the solute potential as the water CONTENT increases in comparison to solutes DISSOLVED. Transpiration doesn’t depend on amount of water present in the system.

Correct answer is (b) Ca

For explanation: Ca is a part of structural component of the plant as it present in the CELL wall, middle lamella and also required for formation of MITOTIC spindle. N and K are present in metabolically active CELLS. P is present in cell membranes, PROTEINS, nucleic acids and nucleotides.

Right choice is (C) Pressure

To elaborate: Bulk flow system OCCURS as a result of difference in pressure. Difference in SIDES of leaf leads to change in amount of photosynthesis, where LOWER leaf carries higher amount of photosynthesis than the upper leaf. Difference in height doesn’t have any role to play as xylem VESSELS take water from lower height to upper height. Difference in temperature leads to change in transpiration rate.

Correct option is (c) Solute potential

Easy explanation: For a solution at atmospheric PRESSURE, the water potential is equal to solute potential. Gravitational potential and MATRIX potential are of negligible importance. Pressure potential is responsible for creating tension in the XYLEM which leads to water transport up a STEM.

Right option is (a) True

Best explanation: WOODY plants have DEAD vascular tissue so there is no conduction of water and do not contain much water. In case of soft PARTS, they have FUNCTIONAL vascular tissue HENCE possess sufficient amount of water.

Correct choice is (b) MATRIX potential

The best I can explain: Matrix potential is the ENERGY developed due the attachment of water with non-dissolved SOLUTES such as soil. It is of negligible value whereas Water potential is the ultimate energy and Solute potential and PRESSURE potential are important components of water potential.

The correct option is (C) passive absorption

Easiest explanation: Water entering roots through DIFFUSION is a passive absorption. Osmosis requires a presence of semi-permeable membrane which is absent in case of roots and soil. ENDOSMOSIS is the process of entry of water inside the guard CELLS when the DPD inside the cell is HIGHER than the surrounding medium.

Correct ANSWER is (b) Thickness of membrane

Easy explanation: Thickness of membrane has no ROLE to play in the movement of molecules from one region to another. The cell membrane, TONOPLAST and membrane of the vacuole must be permeable to the substances, HENCE, are IMPORTANT determinants of the transportation of molecules.

Correct answer is (c) % OPEN STOMATA

To elaborate: % open stoma is an important DETERMINANT of the LOSS due to transpiration. If less NUMBER of stomata is open, less transpirative loss will occur. Temperature, humidity and wind speed affect transpiration externally.

Correct CHOICE is (b) False

For explanation: SUGAR solution flows from region of high turgor PRESSURE to region of low turgor pressure. It is BASED on the WATER potential gradient developed by adjacent xylem carrying out osmosis. It is an active process.

The correct ANSWER is (b) water in soil

To elaborate: Plants obtain hydrogen from water in the soil. Hydrogen from sunlight is formed from FUSION reactions and is helpful in photosynthesis. ATMOSPHERIC hydrogen is INFLAMMABLE and not helpful for plants. Fertilizers are not preferred as a source for hydrogen as it has many side effects. Water is the BEST source of hydrogen for plants.

Right option is (a) True

For EXPLANATION I would say: Mineral ions are moved from MATURE organs to YOUNGER organs of plants before senescence. In DECIDUOUS plants, elements are REMOVED to other parts before all the leaves fall.

The CORRECT ANSWER is (a) True

For explanation: Imbibition is a special type of diffusion which helps solids absorb moisture resulting in INCREASE in volume. In the same WAY, it provides the required pressure for emergence out of the soil to the tiny SEEDLINGS.

Right answer is (a) True

To elaborate: The FUNCTION of the source and sink is interchangeable. During the favorable season, leaves acts as a major source transferring FOOD to sugar STORAGE organs which act as a sink. During dry season, these storage organs act as a source and the sink leaves as well as other organs BECOME the sink.

The correct CHOICE is (b) sucrose

The best I can explain: PHLOEM SAP consists of water and sucrose. Other than those, other SUGARS such as stachyose along with hormones and amino acids are ALSO transported by phloem tissue.

Right choice is (B) False

The explanation: There is no clear distinction that xylem only conducts water and MINERALS, and PHLOEM only conducts ORGANIC food. There is exchange of mineral ions in between them during the process of loading and unloading.

Right OPTION is (a) Ernst Munch

For explanation: Ernst Munch gave the Mass flow HYPOTHESIS. Transpiration STREAM THEORY was given by Henry Dixon. Starch SUGAR Inter-conversion Theory was given by Steward. Adolph Fick gave the diffusion rate theory.

Correct answer is (a) ringing the stem

Easy explanation: Defoliation is the detachment of leaves from the branch. Grafting is a METHOD of vegetative propagation. ROOT pressure is responsible for upward movement of WATER and minerals in xylem. Ringing of stem in girdling experiment is the method of explain the TRANSLOCATION of sucrose is CARRIED out through phloem.

The correct ANSWER is (a) guttation

Best explanation: Guttation is the liquid water loss from SPECIAL openings of veins of leaves. Exudation is liquid which comes out of the pores or wounds. Girdling is the experiment which proves that translocation of food occurs through phloem. TRANSPIRATION is the loss of water from leaf stomata in the FORM of vapors.

The correct option is (c) both xylem and phloem

The explanation is: Vascular BUNDLE is mainly COMPOSED of xylem and phloem. There is PRESENCE of intra-vascular CAMBIUM and inter-vascular cambium in between them in different stages of their life cycle.

Correct answer is (b) root hairs

To explain I WOULD say: Control points or transport proteins are present in endodermal cells of the PLANT system. Root hairs arise from region of maturation of the root system. They help in INCREASING AREA for absorption. EPIDERMAL cells and the cortical cells allow both apoplastic and symplastic pathway.

Correct choice is (d) mycorrhiza

Best EXPLANATION: Mycorrhiza is the symbiotic association of fungus with the ROOT of the plant. Ureides is a form of nitrogen in which nodules of PLANTS like soyabean EXPORT fixed nitrogen. MUTUALISM is the association where both the partners are interdependent such as plants and animals. Nodules are general associations of legume plants and bacteria.

Right answer is (C) positive

To EXPLAIN I would say: Pressure potential is usually positive but it causes negative potential in the XYLEM in order to ENABLE water transport up the stem. Water potential of pure water is ZERO. Solute potential is negative. Gravitational and matrix potential remains relatively constant.

Correct choice is (C) LIPIDS

Explanation: DIFFUSION is faster in SUBSTANCES with molecules having hydrophobic MOIETY. Among the following, lipids have hydrophobic moiety whereas carbohydrates, proteins and vitamins have hydrophilic moiety.

Right answer is (c) MELVIN Calvin

Easiest explanation: Stephan Hales is the Father of Plant Physiology. Schwendener was the first to propose stomatal movements are due to TURGOR changes in the guard cells. Melvin Calvin received Nobel PRIZE in 1961 for MAPPING the pathway of carbon assimilation in photosynthesis. LIPMANN is known as the father of ATP Cycle.

The correct answer is (b) Unidirectional

The EXPLANATION: Xylem transports WATER and minerals in a PARTICULAR DIRECTION from roots to leaves via stem. The movement of phloem is usually BIDIRECTIONAL and sometimes multidirectional.

The correct CHOICE is (C) Leaves

The EXPLANATION: As leaves obtain minerals from soil directly, therefore, acts as a source for MOVEMENT of minerals. Seeds, apical and lateral MERISTEMS and developing fruits and flowers act as sink for mineral elements.

The correct option is (d) CAPILLARITY

The EXPLANATION is: In plants, capillarity is aided by the small diameter of the xylem elements, i.e., the tracheids and vessel elements. Capillarity is the ability to RISE in thin tubes. Cohesion is mutual attraction between molecules of H2O. ADHESION is attraction of water molecules to the surfaces of tracheary elements. Tensile strength is ability to resist a pulling FORCE. Adhesion, cohesion and tensile strength are properties of xylem which enables the ascent of xylem sap.

The correct ANSWER is (d) GOLGI complex

To explain I would say: PLASTIDS, MITOCHONDRIA and some bacteria possess porins but they’re absent in golgi complex.

The correct option is (c) casparian strips

The BEST explanation: Apoplastic pathway is carried out as:

Epidermis -> cortex-> endodermis -> pericycle -> xylem.

Casparian strips are a PART of endodermis which BLOCKS the Apoplastic pathway. It is made up of SUBERIN.

Right answer is (a) ATMOSPHERIC nitrogen

The best explanation: Nitrogen cannot travel in PLANTS in form of atmospheric nitrogen. It has to fixed and converted into inorganic IONS or organic FORMS such as amino ACIDS and ammonia.

Correct option is (b) symplastic pathway

The best I can explain: Symplastic pathway consists of cytoplasm and intercellular MOVEMENT through plasmodesmata. Apoplastic pathway consists of intercellular spaces and walls of the cells. DIFFUSION is simply the movement of water from higher CONCENTRATION gradient and lower concentration gradient. Pressure FLOW of hypothesis is the mechanism of pathway of translocation of sugars from SOURCE to sink.

The CORRECT answer is (d) colloids

Best explanation: Imbibition is USUALLY found in colloids which can absorb other SUBSTANCES. Liquids and GASES are fluids which are ABSORBED. Suspension is formed in centrifugation.

The correct answer is (a) The starch-sugar interconversion theory

To explain I would say: Steward in 1964 proposed a modified scheme of inter-conversion of starch and sugar for stomatal MOVEMENT. Theory of photosynthesis in guard cells was given by Von Mohl in 1856 and proposed that CHLOROPLASTS in the guard cells photosynthesize leading to production of sugar. Theory of GLYCOLATE metabolism was given by Zelitch in 1963 and he proposed that production of glycolic acid in the guard cells is a necessary factor in stomatal OPENING. Active Potassium Pump theory was given by Fujino. Levitt & Rashke in 1975 supported the theory of the K+ ion transport active mechanism requires ATP.

Right option is (b) False

To elaborate: Transpirative loss is studied through cobalt chloride test. The COLOR changes when water is absorbed. Girdling experiment is used to test that phloem TISSUE is responsible for translocation of FOOD. When a ring of BARK is REMOVED up to the depth of the phloem layer and in the absence of downward movement of food, the portion of the bark above the ring of the stem is swollen after a few weeks.

Right answer is (d) VASCULAR tissues

For EXPLANATION: Plasmodesmata is the connections through which cytosol movement take place. Xylem is used for water, MINERALS, organic nitrogen and hormones. Phloem is used for organic and inorganic SOLUTES. Vascular tissues consist of xylem and phloem, together carrying out complete translocation.

Correct answer is (a) 98%

The EXPLANATION is: The amount of water lost by plants due to transpiration and GUTTATION is approximately 98%. Watermelon contains 92% of water. Herbs have 12% of their fresh WEIGHT as the dry matter. Mustard plant absorbs water having 50% of their weight in 5 HOURS.

The correct option is (d) Hypertonic

Easiest explanation: Hypertonic condition is developed during the process of loading at the phloem TISSUE. Isotonic condition develops in equilibrium condition. Hypotonic condition occurs in TURGID cells which then swell as the WATER concentration in CELL increases MANY times.

Correct CHOICE is (a) True

Easy explanation: CYTOPLASMIC streaming is the movement of cytoplasm within a plant or animal cell. It helps in symplastic movement. It is commonly seen in the movement of chloroplast in CELLS of HYDRILLA leaf.