ICAR JRF Plant Form and Physiology — practice questions
99 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice ICAR JRF Plant Form and Physiology in the app →Which two organ systems make up the body of a vascular plant?Plant regions of continuous cell division and growth are known as what?Which meristem occurs only in monocots, at the bases of leaf blades and at nodes?A plant extends in length because of cell division in which tissue?Which plant tissue serves as a site for photosynthesis, supports vascular tissue, and stores water and sugars?Xylem tissue is built from which three cell types?Which statement about phloem conducting cells is correct?In roots, the structure formed by xylem and phloem lying adjacent to each other is called what?The stem region lying between two nodes is called what?Which cell type is the most common in plants and is found in stem, root, leaf and fruit pulp?Elongated support cells with unevenly thickened walls that remain alive at maturity are which type?Which pair of cells makes up sclerenchyma?How are vascular bundles arranged in a monocot stem seen in cross section?Water passes from one vessel element to the next through which structure?Which statement about mature sieve-tube cells is correct?Which cells lie alongside sieve-tube cells and contain more ribosomes and mitochondria than they do?In a stem, the ground tissue lying between the vascular tissue and the epidermis is known as what?An increase in the thickness or girth of a plant is produced by cell division in which meristem?Secondary growth in stems is usually seen in which group?Where does the vascular cambium lie, and what does it produce inwards?The cork cambium produces cork cells containing which water repelling substance?The periderm of a woody stem is made up of which three components?What is the function of lenticels on a mature woody stem?Which change in the secondary xylem produces late wood in the fall season?Besides the age of a tree, what else can an examination of its annual rings reveal?A modified stem that grows horizontally underground and bears nodes and internodes is called what?The eyes of a potato are best described as what?Which pair correctly matches an aerial stem modification with its role?Why does cutting off the top of a branch make a plant grow bushier?Which set names the three major functions of the roots of seed plants?Which root system type is found in monocots such as wheat, rice and corn?Which structure protects the tip of a growing root and is continuously replaced?Moving back from the very tip of a root, in what order do the three zones occur?Roughly how much of the root length do the zones of division, elongation and maturation occupy?The zone of cell maturation in a root begins at which landmark?How do root hairs contribute to the working of a root?How does the ground tissue of a root compare with that of a stem?What does the Casparian strip force water and dissolved solutes to do?Lateral roots arise from which layer of the root?How is the vascular tissue arranged in a monocot root compared with a dicot root?Which description fits an adventitious root?The roots of orchids that allow the plant to grow on another plant develop what?A leaf attached directly to the stem without any stalk is described as what?Which venation pattern is typical of dicot leaves?Three or more leaves connected at a single node is which arrangement?In which leaf type do leaflets radiate outwards from a single point like fingers from a palm?Botanists call the lower side of a leaf by which name?Which waxy layer covering the leaves of all plant species reduces the rate of water loss?Which of these is a stated function of leaf trichomes?Which mesophyll layer is built from column shaped, tightly packed cells?Which epidermal cells are the only ones to contain chloroplasts?What is true of every vascular bundle in a leaf, however large or small?Two features of conifer needles that reduce water loss in cold environments are which?Insect capturing leaves are thought to give carnivorous bog plants a supplementary source of what?What are pneumatophores, found in some mangroves and cypress trees?The air filled tissue in the root cortex of wild rice serves what purpose?How do tropical epiphytes obtain the water and minerals they need?Water potential is best defined as which quantity?Water potential is expressed in which units, and what value is assigned to pure water?Between two connected compartments, water moves in which direction?For water to move from the soil through the plant and into the air, which order of water potentials must hold?Adding solutes to an aqueous system has what effect on its water potential?Which component of water potential can a plant cell control metabolically?What is the highest pressure potential quoted for a well watered plant?A pressure potential of 1.5 MPa is equivalent to about how many pounds per square inch?Gravity potential in a standing plant has which character?Matric potential arises from water binding to which kind of component?What is the main driver of water movement in the xylem?At night, when stomata shut and transpiration stops, what holds the water column in the stem and leaf?What is the consequence of cavitation in a tall tree?Why is transpiration described as a passive process?What share of the water taken up by roots may be lost through transpiration?Guard cells open and close in response to which set of cues?How does the cuticle of a xerophyte compare with that of a mesophyte?In phloem transport, which structures are correctly described as sinks?How is sucrose loaded from mesophyll cells into the phloem sieve-tube elements?Phloem sap is an aqueous solution containing up to what percentage of sugar?In the pressure driven movement of phloem sap, where does the water that raises the pressure come from?How does the direction of flow in the xylem differ from that in the phloem?During reproductive development, photosynthates are directed primarily to which destination?The ability of a plant to use light to track time is called what?Which statement about light absorption by the two forms of phytochrome is correct?A leaf shaded by another plant receives far red enriched light. What follows?Why do very small seeds such as lettuce fail to germinate in the dark?Short-day plants flower at which point in the year, and on what cue?The chromophore of a phototropin is a covalently bound molecule of what?In the 1913 experiment, what happened when impermeable mica flakes were inserted between a seedling tip and itDuring phototropism, where does indole acetic acid accumulate and what does it do there?Which blue light receptors set the 24 hour activity cycle of a plant?Which organelles settle downward in gravity sensing cells and are also called statoliths?A tilted seedling redistributes indole acetic acid to its lower side. What happens in the root and in the shooWhich is the only naturally occurring auxin that shows physiological activity?The effect of cytokinins was first reported after adding what to plant embryos in culture?Gibberellins are described as a group of about how many closely related hormones?Low soil moisture raises the level of abscisic acid, which then does what?In ripening fruit, ethylene stimulates which conversion?Jasmonates elicit the synthesis of volatile compounds that attract which agents?A tree exposed to constant strong wind shows which developmental response?Which defence compound of the cassava root becomes toxic only after a herbivore eats it?