MCQs on Plant Physiology: Introduction and Sample Questions

Ans. c) Negative geotropism.

Explanation: The movement of plant parts in response to the attraction of gravity is known as geotropism. if the movement of the plant parts is against gravity then it is called as negative geotropism. When a plant in a vase is positioned horizontally to the ground, the shoot acquires an upright growth, opposite of the pull of gravity indicating negative geotropism.

Ans. c) Stephan Hales.

Explanation: Root pressure theory explains It is a pressure that has been created in the xylem's tracheary components as a result of root metabolism. Root pressure is an osmotic phenomenon that was created as a result of the action of root cells. This theory is given by Stephen Hales in 1727.

Ans. a) Higher.

Explanation: C4 plants show more efficiency than C3 plants due to carbon fixation. C4 plants are more efficient to fix carbon atoms in drought areas also.C4 plants have higher photosynthesis rates about 50-75. RuBisCO is the primary carbon fixation enzyme in the Calvin cycle. When the carbon dioxide concentration is low, RuBisCO absorbs oxygen to conduct photorespiration. Since the RuBisCO site has a high concentration of carbon dioxide, photorespiration is significantly reduced in C4 plants.

Ans. d) 0.

Explanation: R.Q is the respiratory quotient. It is defined as the ratio of the carbon dioxide exhaled to the oxygen inhaled. In succulent plants at night, the stomata are open due to which oxygen is evolved but no carbon dioxide is evolved so the value of R.Q is 0.

Ans. a) Moist seed in low temperature.

Explanation: Stratification is a process in which seeds were pre-treated in order to stimulate the natural conditions that seeds could experience in the soil during the winter season. In winter temperature is low so it is treated with stratification. The seed is combined with wet inert material and stored cold for ten days to three months, and then the procedure is called "moist stratification."

Ans. d) None of these.

Explanation: Physiology disorder is a non-pathological condition that can occur due to any reason poor light, adverse weather, water-logging, or lack of nutrients. It is the irregular development pattern or abnormal external or internal conditions of fruits. Physiological disorders are due to adverse environmental conditions. So none of these are related to environmental conditions.

Ans. b) Grana of the chloroplast.

Explanation: The photochemical splitting of water yields oxygen in the presence of appropriate electron acceptors such as potassium ferrioxalate and potassium ferricyanide. The Hill response is what is meant by this. There is light present when this occurs. The hill reaction is the transfer of electrons from water to hill reagents in the direction against the chemical potential gradient as a part of photosynthesis. It is a photochemical reaction that takes place in the grana of chloroplast.

Ans. a) True.

Explanation: Concentration gradient is the process that occurs when the concentration of a particle is higher in one area than another. In a concentration gradient diffusion occurs no matter which process is involved. In order to move the chemicals from one location to another, all the activities require a redox potential.

Ans. d) Golgi complex.

Explanation: Porins are proteins that form in pores of large size in the outer membrane of the plastids like in chloroplasts. The most prevalent protein in the mitochondrial outer membrane is called porin, which is also known as the voltage-dependent anion channel. Porins are proteins present in the outer membrane. The outer membrane is not present in the Golgi complex.

Ans. c) Lipids.

Explanation: Diffusion is a process of movement of molecules from a region of higher concentration to a region of lower concentration. Diffusion across the membrane depends upon solubility in lipids. The ER and the outer and inner nuclear membranes are examples of membrane continuities through which lipids can first laterally diffuse. Lipids store energy for long-term use and provide insulation for plants.

Ans. b) Physical process.

Explanation: Diffusion is the process of movement of molecules from a region of higher concentration to a region of lower concentration. Diffusion is a physical and natural process that occurs in gases and liquids because random molecular movement is possible. The molecules run against one another and veer in a different direction. Diffusion is an important process for photosynthesis where carbon dioxide diffuses from the stomata to the leaves. It is a physical process.

Ans. a) p.

Explanation: Nucleic acid comes in two natural forms known as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Elements present in nucleic acid, ATP, and ADP are nitrogen, oxygen, carbon, phosphorus, and hydrogen. Phosphorus is an essential element since it is found in both ADP and ATP. It contributes to the formation of the phosphate group in adenosine triphosphate (ADP) and adenosine diphosphate (ATP). A crucial macronutrient for plants is phosphorus. DNA is found in found every organism.

Ans. a) Fe and Mg.

Explanation: Chlorophyll is the key process in photosynthesis. Due to chlorophyll plants get their green colour. Magnesium is present in the centre of the pigment of chlorophyll. Iron deficiency causes chlorophyll degeneration. Iron and magnesium are the essentials for photosynthesis. These elements' deficiencies result in the yellowing of the leaves and chlorotic spots on the foliage.

Ans. a) Calcium pectate.

Explanation: Calcium is an essential nutrient for living organisms. Calcium combined with pectin forms a glue that holds the cells together. Calcium pectate forms a salt that helps in keeping cell walls rigid and tough. Calcium is present in the form of calcium pectate. Pectate functions as a chelator to bind calcium and create cross-links that hold together neighboring pectate polymers and, in turn, the walls of plant cells.

Ans. b) B.

Explanation: The major function of pollen germination is to deliver sperm cells in the ovule to ensure successful fertilization. the result of many studies has also revealed that calcium is the critical element in pollen germination. boron is a micronutrient that is required for pollen germination, root modulation and cell elongation.

Ans. d) Mn.

Explanation: Mn is essential to split water and form an oxygen-evolving complex for photosynthesis. and Mn forms strong nitrogen and S ligands. Mn is selected overall due to greater functionality. In order to substitute noble metal catalysts in the oxygen evolution process, manganese oxide is thought to be a suitable material. Thus, Mn is essential for the evolution of oxygen during photosynthesis.

Ans. b) Oxidation.

Explanation: Oxidation is the loss of electrons and gaining oxygen. When nitrogen combines with the element or compound Nitrogen during the oxidation process adds oxygen to nitrous into nitric acid. Nitrobacteria oxidize nitrite to nitrate in the soil. Nitrobacter uses energy from the oxidation of nitrite ions (NO^2-), into nitrate ions (NO^3-), to fulfill their energy needs.

Ans. c) is the characteristics of all living cells.

Explanation: Respiration is a metabolic process in which living cells of organisms obtain energy. By taking in oxygen and exhaling carbon dioxide. Respiration is important for the growth of plants and the maintenance of all plant tissues. This energy is also important for the growth of plants. Respiration is the characteristic of all living cells in plants.

Ans. c) water-saturated sand.

Explanation: Hydroponics is a type of horticulture in which all plants were grown by using water-based minerals and nutrient solutions. In the case of aquatic plants plants grow in the environment of exposed nutritious liquid. Hydroponics is a kind of technique in which plants were grown in a balanced nutrition solution.

Ans. c) Gymnosperms.

Explanation: Gymnosperms are tall plants and root pressure would not be able to transport water up to the height of the plant. Another reason is that Gymnosperms lack xylem vessels, leading to no root pressure. Root pressure is thus not a feasible option for tall plants like gymnosperms for the transport of fluids.