- Transport in Plants: As described earlier, plant physiology is the study of life-sustaining functions and as plants do not show locomotion, it is of utmost importance to understand how are they taking up various nutrient and water from the surrounding. Therefore, the chapter transport in plant deals with the ascent of sap and translocation of food. As you are already familiar with the complex tissues of xylem and phloem, you will appreciate the functioning of the same in this chapter. You will also realise the importance of water for the plants. It can be equated with blood in animals! The following sub-topics need to be studied with attention:
a) Means of transport: diffusion and its types; osmosis.
b) Plant-water relations: water potential, solute potential, matrix potential, plasmolysis, tonicity of solutions, Imbibition.
c) Long-distance transport in plants: translocation, absorption of water by roots (you will have to revise the anatomical details of the root).
d) Water Movement up a Plant: root pressure, transpiration pull, cohesion-adhesion theory.
e) Phloem Transport: Flow From Source To Sink
- Mineral Nutrition: The topics of plant physiology in this chapter are somewhat based on chapter biomolecules. Herein, you will understand the macronutrients and micronutrients required for the proper functioning of the plant system. The focus is laid on the inorganic mineral nutrition obtained from the soil and atmosphere. Hence, there will also be the concepts of nutrient cycles, namely nitrogen cycle, oxygen cycle, phosphorus cycle and the water cycle. This chapter also deals with the study of deficiency disorders in plants when mineral nutrition are not supplied as per the need. Nonetheless, the topics of this chapter can be summarised under the following heads:
Method to Study the Mineral Requirements of Plants: a detailed description of hydroponics.
Essential Mineral Elements: Criteria for the essentiality of the minerals, the role of macro and micronutrients, deficiency symptoms of essential elements, the toxicity of micronutrients.
Mechanism of Absorption of Elements: Bulk-flow hypothesis.
Translocation of Solutes
Soil as a Reservoir of Essential Elements
Metabolism of Nitrogen: nitrogen cycle, nitrogen fixation and nodule formation in leguminous plants.
- Photosynthesis in Higher Plants: It is one of those topics of plant physiology that intrigue the brains of both the teachers and students! Based on the concepts of biochemistry, the topic photosynthesis is highly recommended for proper reading because it offers a variety of questions. Let us understand the flow of photosynthesis as mentioned in the NCERT along with the additional concepts required for NEET preparation:
Brief description of the historical aspects of understanding photosynthesis, such as Priestley’s Experiment.
Site of photosynthesis - detailed analysis of chloroplast, structure, and types of chlorophyll molecules, action and absorption spectra of chlorophyll.
Phases of photosynthesis - events of light reaction and dark reaction, electron transport, splitting of water, cyclic and non-cyclic photophosphorylation, chemiosmotic hypothesis.
The utility of ATP and NADPH
The Calvin cycle, C4 pathway, CAM pathway.
Photorespiration
Factors affecting photosynthesis.
- Respiration in Plants: The topics of respiration in plants are conceptually at par with the topics of photosynthesis. The respiration in plants also involves the biochemical pathways. Additionally, the concepts of this chapter would be appliable in human physiology too. Hence, you will keep the understanding-of-the-concept mode on even for this chapter! Let us have a glance at the topics from the NCERT textbook as well as from the NEET syllabus:
The concept of respiration and breathing, how do plants breathe?
Aerobic and anaerobic respiration
Glycolysis, fermentation
TCA cycle and electron transport chain, the structure of mitochondria
Oxidative phosphorylation
The respiratory balance sheet
Respiratory quotient
5. Plant Growth and Development: The topics of this chapter are equivalent to the nervous system of animals. You will understand the plant hormones and their roles in regulating as well as coordinating various developmental aspects of plants. The significance of light in the growth of the plant will also be the topic of focus. After reading this chapter, you will be able to:
Define and characterize the growth in plants
Understand the difference between differentiation, dedifferentiation and
redifferentiation
Define and characterise the plant growth regulators or plant hormones
Know about the physiological effects of auxins, gibberellins, cytokinins, ethylene, and abscisic acid
Know about the physiology of seed dormancy
Know about the physiology of vernalization
Know about the physiology of photoperiodism, long-day plants, short-day plants and day-neutral plants.