Description : How do guard cells regulate opening and closing of stomatal pores ? -Science
Last Answer : The opening and closing of stomatal pores is controlled by the guard cells, when water flows into the guard cells, they swell, become curved and cause the pore to open whereas when the guard cells lose water, they shrink, become straight and close the stomatal pore
Description : (a) Draw a diagram to show open stomatal pore and label on it: (i) guard cells (ii) chloroplast (b) State two functions of stomata. (c) How do guard cells regulate the opening and closing of stomatal pore? -Biology
Last Answer : (a) (b) Two functions of stomata are: (i) Exchange of gases between the plant and the atmosphere takes place through stomata. (ii)Transpiration in plants takes place through stomata. ( ... through these stomata, the plant closes these pores when it does not require carbon dioxide for photosynthesis.
Description : The exchange of gases takes place in the leaves through these pores for the purpose of photosynthesis. These pores are called – (1) Guard Cells (2) Stomata (3) Chloroplast (4) None of the above
Last Answer : (2) Stomata Explanation: Stomata are tiny pores present on the surface of the leaves via which exchange of gases takes place in the leaves for the purpose of photosynthesis. However, exchange of gases also occurs across the surface of stems, roots and leaves as well.
Description : Stomatal opening is based on (1) Exosrnosis (2) Endosmosis (3) Plasmolysis in guard cells (4) Decrease in concentration of cell sap
Last Answer : (2) Endosmosis Explanation: According to the K+ ion theory the guard cells absorb K+ ions from the cells around them as they produce ATP (due to photosynthesis) and become ... guard cells become turgid and the stomata opens. Decreasing light intensity and photosynthesis causes Stomatal closing.
Description : Which of the following facilitates opening of stomatal aperture? (a) Decrease in turgidity of guard cells (b) Radial orientation of cellulose microfibrils in the cell wall of guard cells (c) ... microfibrils in the cell wall of guard cells (d) Contraction of outer wall of guard cells
Last Answer : (a) Decrease in turgidity of guard cells
Description : Which of the following facilitates opening of stomatal aperture ? (1) Decrease in turgidity of guard cells (2) Radial orientation of cellulose microfibrils in the cell wall of guard cells (3) Longitudinal ... microfibrils in the cell wall of guard cells (4) Contraction of outer wall of guard cells
Last Answer : (2) Radial orientation of cellulose microfibrils in the cell wall of guard cells
Description : Stomatal opening is based on (1) Exosmosis (2) Endosmosis (3) Plasmolysis in guard cells (4) Decrease in concentration of cell sap
Last Answer : Endosmosis
Description : Which of the following is responsible for transport of food and other substances in plants? (1) Xylem (2) Phloem (3) Chloroplast (4) None these
Last Answer : (2) Phloem Explanation: The transport of water, nutrients and other substances from one part of a plant to another is called translocation. While, phloem transports synthesized food from the ... the plant body; water and minerals are transported from the roots upwards through the xylem tubes.
Description : Which of the following is responsible for transport of food and other substances in plants? (1) Xylem (2) Phloem (3) Chloroplast (4) None of these
Description : Which of the following is responsible for transport of food and other substances in plants ? (1) Xylem (2) Phloem (3) Chloroplast (4) None of these
Last Answer : Phloem
Description : Explain the mechanism of stomatal opening and closing. -Biology
Last Answer : answer:
Description : Conversion of starch to sugar is essential for - (1) Stomatal opening (2) Stomatal closing (3) Stomatal formation (4) Stomatal growth
Last Answer : (1) Stomatal opening Explanation: For keeping the stomata open a constant expenditure of energy is required. This is provided by the conversion of starch to sugar. The stomata! opening is, in turn ... at the leaves while their stomata are open for the passage of CO2 and 02 during photosynthesis.
Description : Conversion of starch to organic acids is required for (a) stomatal opening (b) stomatal closing (c) stomatal formation (d) stomatal activity.
Last Answer : a) stomatal opening
Description : Conversion of starch to sugar is essential for (1) Stomatal opening (2) Stomatal closing (3) Stomatal formation (4) Stomatal growth
Last Answer : Stomatal opening
Description : Opening and closing of stomata is due to the (a) hormonal change in guard cells (b) change in turgor pressure of guard cells (c) gaseous exchange (d) respiration.
Last Answer : (b) change in turgor pressure of guard cells
Description : Which process controls the opening and closing of the pores ?
Last Answer : The percolation process controls the opening and closing of the pores.
Description : The special modified epiderniai cells surrounding stomatal pore are called - (1) Epithelial cells (2) Guard cells (3) Subsidiary cells (4) Accessory cells
Last Answer : (2) Guard cells Explanation: The pore is bordered by a pair of specialized parenchyma cells known as guard cells that are responsible for regulating the size of the opening. Guard cells are specialized cells in the epidermis of leaves, stems and other organs that are used to control gas exchange.
Description : In guard cells when sugar is converted into starch, the stomatal pore (a) closes completely (b) opens partially (c) opens fully (d) remains unchanged.
Last Answer : a) closes completely
Description : Which of the following statements is not true for stomatal apparatus? (a) Guard cells invariably possess chloroplasts and mitochondria. (b) Guard cells are always surrounded by subsidiary cells. (c) Stomata are involved in gaseous exchange. (d) Inner wall of guard cells are thick
Last Answer : (b) Guard cells are always surrounded by subsidiary cells.
Description : The special modified epidermal cells surrounding stomatal pore are called (1) Epithelial cells (2) Guard cells (3) Subsidiary cells (4) Accessory cells
Last Answer : Guard cells
Description : Which tissue is responsible for the passage of water in plants? (a) Sclerenchyma (b) Xylem (c) Phloem (d) Collenchynatous cells
Last Answer : Ans:(b)
Description : The xylem and phloem elements in the plant are surrounded by a layer of living cells called (a) Casparian strips (b) Pericycle (c) Stele(d) Endodermis
Last Answer : (b) Pericycle
Description : The principal pathway of water translocation in angiosperms is (a) sieve cells (b) sieve tube elements (c) xylem vessel system (d) xylem and phloem
Last Answer : a) sieve cells
Description : Which of the following is made up of dead cells? (a) Collenchyma (b) Phellem (c) Phloem (d) Xylem parenchyma
Last Answer : (b) Phellem
Description : You are given a fairly old piece of dicot stem and a dicot root. Which of the following anatomical structures will you use to distinguish between the two? (a) Secondary xylem (b) Secondary phloem (c) Protoxylem (d) Cortical cells
Last Answer : (c) Protoxylem
Description : Which of the following is made up of dead cells? (1) Collenchyma (2) Phellem (3) Phloem (4) Xylem parenchyma
Last Answer : (2) Phellem
Description : The CO2 fixation during C4 pathway occurs in the chloroplast of (a) guard cells (b) bundle sheath cells (c) mesophyll cells (d) spongy parenchyma.
Last Answer : (c) mesophyll cells
Description : Which one gives the most valid and recent explanation for stomatal movement? (a) Starch hydrolysis (b) Guard cell photosynthesis (c) Transpiration (d) Potassium influx and efflux
Last Answer : (d) Potassium influx and efflux
Description : Given below is the diagram of a stomatal apparatus. In which of the following all the four parts labelled as A, B, C and D are correctly identified? A B C D A B C D ... ) Epidermal Guard cell Stomatal Subsidiary cell cell aperture (d) Epidermal Subsidiary Stomatal Guard cell cell cell aperture
Last Answer : d) Epidermal Subsidiary Stomatal Guard cell cell cell aperture
Description : What are the differences between the transport of materials in xylem and phloem ? -Biology
Last Answer : Xylem Phloem 1. Xylem conducts water and dissolved minerals from roots to leaves and other parts. 1. Phloem conducts prepared food material from leaves to other parts of plant in dissolved ... increases the osmotic pressure that moves the material in the phloem to tissues which have less pressure
Description : Which are the first terrestrial plants to possess xylem and phloem?
Last Answer : Which are the first terrestrial plants to possess xylem and phloem?
Description : What part of a leaf contains xylem and phloem?
Last Answer : Need answer
Description : What are the xylem and phloem of plants used for?
Last Answer : Xylem tissue is used mostly for transporting water from roots to stems and leaves but also transports other dissolved compounds. Phloem is responsible for transporting food produced from photosynthesis from leaves to non-photosynthesizing parts of a plant such as roots and stems.
Description : Leptome is used for: (a) Phloem (c) Fibres (b) Xylem (d) Parenhyma
Last Answer : Ans. ((a))
Description : What tissue present in leaves of Pinus conducts food and water laterally? (a) Transfusion tissue (b) Phloem (c) Xylem (d) Medullary rays
Description : What is the difference between xylem and phloem ?
Last Answer : Both xylem and phloem are vascular tissues found in a plant. Xylem is a tubular structure, which is responsible for water transport from the roots towards all of the parts of the plant. Phloem ... the other hand, is responsible for the transportation of food and other nutrients needed by plant.
Description : The tissue that is involved in the transport of food material in plants is called: (a) parenchyma (b) phloem (c) sclerenchyma (d) xylem
Description : If xylem and phloem are arranged in the same radius, such a vascular bundle is called : (1) collateral (2) bicollateral (3) concentric (4) radial
Last Answer : (1) collateral Explanation: In the collateral type of vascular bundle, xylem and phloem are arranged side by side on the same radius. This may be either open or closed. Usually xylem is seen ... the inner side and phloem towards outer side. The collateral vascular bundle is also known as conjoint.
Description : Water conduction takes place in mosses through – (1) Xylem and Phloem (2) Xylem (3) Collenchyma (4) Parenchyma
Last Answer : (4) Parenchyma Explanation: Botanically, mosses are nonvascular plants that absorb water and nutrients mainly through their leaves and harvest carbon dioxide and sunlight to create food by photosynthesis. ... They do not have a welldeveloped xylem. Their conducting tissue is made up of parenchyma.
Description : The food conducting tissue of a plant is (1) Phloem (2) Xylem (3) Parenchyma (4) Collenchyma
Last Answer : (1) Phloem Explanation: In vascular plants, phloem is the living tissue that carries organic nutrients, in particular, sucrose, a sugar, to all parts of the plant where needed. ... mainly with the transport of soluble organic material made during photosynthesis. This is called translocation.
Description : Ascent of sap in plants takes place through – (1) Pith (2) Phloem (3) Cambium (4) Xylem
Last Answer : (4) Xylem Explanation: The ascent of sap in the xylem tissue of plants is the upward movement of water from the root to the crown. Xylem is a complex tissue consisting of living and ... cells in xylem are typically nonliving and include, in various groups of plants, vessels members and tracheids.
Description : Which of the following moves/transports water and mineral from the soil to other parts of the plants? (1) Phloem (2) Xylem (3) Chlorophyll (4) Roots
Last Answer : (2) Xylem Explanation: Xylem moves water and minerals obtained from the soil. The other, phloem transports products of photosynthesis from the leaves to other parts.
Description : Water in plants is transported by - (1) cambium (2) phloem (3) epidermis (4) xylem
Last Answer : (4) xylem Explanation: Water is transported through the plant in Xylem vessels, these begin in the roots and end in the leaves of the plant, water is translocated through a combination of ... photosynthesis (glucose) through the plant, the tissue responsible for moving the "food" around is Phloem.
Description : Mention the differences between xylem and phloem.
Last Answer : Xylem 1) It conducts water and minerals from roots to other parts of the plant body Phloem 1) It transports food from leaves to other regions.
Description : Why are xylem and phloem called vascular bundles?
Last Answer : Since xylem and phloem occur together they are called vascular bundles.
Description : Jute fibre is extracted from ? a Xylem b Parenchyma c Secondary phloem d Epidermal layer
Last Answer : c Secondary phloem
Description : Highest auxin concentration occurs (a) in growing tips (b) in leaves (c) at base of plant organs (d) in xylem and phloem
Last Answer : (a) in growing tips
Description : Which is correct about transport of conduction of substances? (a) Organic food moves up through phloem (b) Organic food moves up through xylem (c) Inorganic food moves upwardly and downwardly through xylem (d) Organic food moves upwardly and downwardly through phloem
Last Answer : (d) Organic food moves upwardly and downwardly through phloem
Description : Bidirectional translocation of solutes takes place in (a) parenchyma (b) cambium (c) xylem (d) phloem.
Last Answer : (d) phloem.
Description : Minerals absorbed by root move to the leaf through (a) xylem (b) phloem (c) sieve tubes (d) none of the above.
Last Answer : (a) xylem