Description : Phloem in gymnosperms lacks (a) both sieve tubes and companion cells (b) albuminous cells and sieve cells (c) sieve tubes only (d) companion cells only.
Last Answer : (a) both sieve tubes and companion cells
Description : Phloem in gymnosperms lacks (a) both sieve tubes and companion cells (b) albuminous cells and sieve cells (c) sieve tubes only (d) companion cells only
Description : State the function of a) sieve tubes b) sieve plate c) companion cells d) phloem fibres.
Last Answer : a) Sieve tubes: They play an important role in the conduction of food. b) Sieve plate: It allows the food to pass through the pores. c) Companion cells: They control the passage of food through the phloem. d) Phloem fibres: They provide tensile strength to the plant body.
Description : Which of the following plant cells will show totipotency? (a) Sieve tubes (b) Xylem vessels (c) Meristem (d) Cork cells
Last Answer : (c) Meristem
Description : The translocation of organic solutes in sieve tube members is supported by (a) cytoplasmic streaming (b) root pressure and transpiration pull (c) P-proteins (d) mass flow involving a carrier and ATP
Last Answer : (a) cytoplasmic streaming
Description : $ Seive tubes in plants are formed of enucleated cells called seive members. ! All the activities of a seive cell are controlled by nucleated parenchy
Last Answer : $ Seive tubes in plants are formed of enucleated cells called seive members. ! All the activities of a seive ... wrong D. If both As and R are wrong.
Description : Identify the two components of Phloem tissue that help in transportation of food in plants (a) Phloem parenchyma & sieve tubes (b) Sieve tubes & companion cell. (c) Phloem parenchyma & companion cell. (d) Phloem fibres and sieve tubes
Last Answer : (b) Sieve tubes & companion cell.
Description : What are sieve tubes?
Last Answer : Sieve tubes comprise of longitudinally arranged cells. The cells are joined end to end in a series. At maturity the cells lose the nucleus.
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
Description : Sieve tubes are suited for translocation of food because they possess (a) bordered pits (b) no end walls (c) broader lumen and perforated cross walls (d) no protoplasm
Last Answer : (c) broader lumen and perforated cross walls
Description : An organised and differentiated cellular structure having cytoplasm but no nucleus is (a) vessels (b) xylem parenchyma (c) sieve tubes (d) tracheids.
Last Answer : (c) sieve tubes
Description : Companion cells are closely associated with (a) sieve elements (b) vessel elements (c) trichomes (d) guard cells.
Last Answer : a) sieve elements
Last Answer : (a) sieve elements
Description : Companion cells are closely associated with (1) Guard cells (2) Sieve elements (3) Vessel elements (4) Trichomes
Last Answer : (2) Sieve elements
Description : $ Those plants which produce seeds, without the formation of fruits are called Gymnosperms. ! Endosperm is triploid in Angiospherms
Last Answer : $ Those plants which produce seeds, without the formation of fruits are called Gymnosperms. ! Endosperm is ... D. If both As and R are wrong.
Description : $ Angiosperms produce seeds, but do not produce fruits. ! Fruit and seed formation occurs in Gymnosperms.
Last Answer : $ Angiosperms produce seeds, but do not produce fruits. ! Fruit and seed formation occurs in Gymnosperms. A. ... wrong D. If both As and R are wrong.
Description : $ Tracheophytes are the plants with vascular tissues. ! Tracheophytes are of three types (i) Pteridophytes (ii) Gymnosperms (iii) Angiosperms
Last Answer : $ Tracheophytes are the plants with vascular tissues. ! Tracheophytes are of three types (i) Pteridophytes (ii ... D. If both As and R are wrong.
Description : $ Rhodopsin of rod cells and iodospin of cone cells of retina are proteins ! Myosine and Actin are contractile proteins
Last Answer : $ Rhodopsin of rod cells and iodospin of cone cells of retina are proteins ! Myosine and Actin are ... wrong D. If both As and R are wrong.
Description : Consider the following statements: (1) The seed of pea is exalbuminous (2) The fruit of peach is drupe (3) The seed of tomato is albuminous (4) The fruit of coconut is berry
Last Answer : Ans. ((b))
Description : Albuminous seeds store their reserve food mainly in (a) endosperm (b) cotyledons (c) hypocotyl (d) perisperm.
Last Answer : (a) endosperm
Description : Non-albuminous seed is produced in (a) maize (b) castor (c) wheat (d) pea.
Last Answer : d) pea.
Description : Which of the following is dicotyledonous albuminous seed — a. Soybean b. Cotton c. Sweet pea d. Castor
Last Answer : d. Castor
Description : Pasteurisation of milk means (A) Removal of fatty and albuminous substance from it (B) Killing of organisms present in it by heating it at controlled temperature without changing its natural characteristics (C) Inhibiting the growth of micro-organisms without killing them (D) None of these
Last Answer : (B) Killing of organisms present in it by heating it at controlled temperature without changing its natural characteristics
Description : A common structural feature of vessel elements and sieve tube elements is (a) enucleate condition (b) thick secondary walls (c) pores on lateral walls (d) presence of P-protein
Last Answer : (a) enucleate condition
Description : A common structural feature of vessel elements and sieve tube elements is (a) enucleate condition (b) thick secondary walls (c) pores on lateral walls (d) presence of P-protein.
Description : Tyloses are: (a) Lactiferous channels (b) Secretory cells (c) Sieve plates (d) Tracheal plugs plugging the lumen of vessels and tracheids
Last Answer : Ans. ((d))
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 : Bordered pits are found in (a) sieve cells (b) vessel wall (c) companion cells (d) sieve tube wall.
Last Answer : (b) vessel wall
Description : Transport of food material in higher plants takes place through (a) companion cells (b) transfusion tissue (c) tracheids (d) sieve elements.
Last Answer : (d) sieve elements.
Description : Function of companion cells is (a) providing energy to sieve elements for active transport (b) providing water to phloem (c) loading of sucrose into sieve elements by passive transport (d) loading of sucrose into sieve elements.
Last Answer : (d) loading of sucrose into sieve elements.
Description : Bordered pits are found in (a) sieve cells (b) vessel wall (c) companion cells (d) sieve tube wall
Last Answer : d) sieve elements.
Description : Companion cells in gymnosperms? -Biology
Last Answer : answer:
Description : Companion cells of phloem are found in – (1) Gymnosperms (2) Bryophyta (3) Pteridophyta (4) Angiosperms
Last Answer : (4) Angiosperms Explanation: Only in angiosperms are sieve tubes and companion cells found in the plaloern. In other vascular plants, parenchyma cells function in the same way as companion cells (that ... living protoplasm), but they are not derived from the same mother cell as the sieve element.
Description : .A well developed archegonium with neck consisting of 4-6 rows and neck canal cells, characterises (a) gymnosperms and flowering plants (b) pteridophytes and gymnosperms (c) gymnosperms only (d) bryophytes and pteridophytes
Last Answer : d) bryophytes and pteridophytes.
Description : Companion cells of phloem are found in (1) Gymnosperms (2) Bryophyta (3) Pteridophyta (4) Angiosperms
Last Answer : Angiosperms
Description : $ Spirulina is a rich source of proteins. ! Spirulina has a spiral chloroplasts.
Last Answer : $ Spirulina is a rich source of proteins. ! Spirulina has a spiral chloroplasts. A. If both As and R are ... is wrong D. If both As and R are wrong.
Description : $ In conjugated proteins, the protein molecule is joined to a non proteins group called prosthetic group. ! Nucleproteins are a type of conjugated pro
Last Answer : $ In conjugated proteins, the protein molecule is joined to a non proteins group called prosthetic group. ! ... wrong D. If both As and R are wrong.
Description : $ Coenzymes are usually proteins ! The term feedback refers to the effect of enzyme concentration on its rate of reaction.
Last Answer : $ Coenzymes are usually proteins ! The term feedback refers to the effect of enzyme concentration on its rate ... wrong D. If both As and R are wrong.
Description : $ Enzymes are special types of proteins. ! Those substances which interfere with the action of enzymes are called inhibitors.
Last Answer : $ Enzymes are special types of proteins. ! Those substances which interfere with the action of enzymes are ... wrong D. If both As and R are wrong.
Description : $ Proteins, polysaccharides and nucleic acid are the macromolecules of a cell. ! DNA contains Ribose Sugar.
Last Answer : $ Proteins, polysaccharides and nucleic acid are the macromolecules of a cell. ! DNA contains Ribose Sugar. A ... wrong D. If both As and R are wrong.
Description : What is the difference between a complete digestive system and an incomplete digestive system? How are these types of digestive tubes associated or not to extracellular digestion?
Last Answer : Animals with an incomplete digestive system are those in which the digestive tube has only one opening (cnidarians, platyhelminthes). Animals with a complete digestive system are those ... . In animals with complete digestive systems extracellular digestion within the digestive tube predominates.
Description : CD 3 complex and p 56lck proteins are present in (A) Cytotoxic T cells (B) Helper T cells (C) Both (A) and (B) (D) None of these
Last Answer : Answer : D
Description : A dumper is filled in 15hrs by 3 tubes P,Q,and R. the tube R is thrice as fast as Q and Q is thrice as fast as P. How much time will tube Q alone take to fill the tank? A) 195hrs B) 190hrs C) 185hrs D) 180hrs
Last Answer : A Suppose tube P alone takes x hrs to fill the tank Then tubes Q and R will take x/3 and x/9 hrs respectively to fill the dumper. Therefore 1/x + 3/x+ 9/x = 1/15 13x = 1/15 X = 195 hrs
Description : Which cells are like short tubes ?
Last Answer : Vessel cells are like short tubes.
Description : The type of epithelial cells which line the inner surface of Fallopian tubes, bronchioles and small bronchi are known as
Last Answer : The type of epithelial cells which line the inner surface of Fallopian tubes, bronchioles ... epithelium C. Cilated epithelium D. Cubical epithelilum