The “Source and Sink Theory”, simply indicates that “if there is a source, it must be at least one sink (at the same instance), with a flow pattern from source to the sink, and the process must be conserved”.
How does phloem transport products from the source to the sink?
Sap moves through phloem via translocation, the transport of dissolved materials in a plant. Unlike the xylem, which can only carry water upward, phloem carries sap upward and downward, from sugar sources to sugar sinks: Sugar sources are plant organs such as leaves that produce sugars.
How are solutes translocated from source to sink?
In this article we will discuss about the Flow of Source and Sink in Phloem Translocation. Since the source-sink relationship is variable, the direction of movement of organic solutes in phloem can be upwards or downwards i.e., bidirectional (c.f. unidirectional upwards in xylem).
What is source and sink in fluid mechanics?
Sink flow is the opposite of source flow. The streamlines are radial, directed inwards to the line source. As we get closer to the sink, area of flow decreases. In order to satisfy the continuity equation, the streamlines get bunched closer and the velocity increases as we get closer to the source.
What is translocation of solutes?
The movement of organic food material or solutes from one place to another in higher plants is called translocation of organic solutes.
How translocation occurs in the phloem?
Sugars produced in sources, such as leaves, need to be delivered to growing parts of the plant via the phloem in a process called translocation, or movement of sugar. The photosynthates from the source are usually translocated to the nearest sink through the phloem sieve tube elements.
What do you mean by translocation of solutes?
The movement of organic food materials or the solutes in soluble form one place to. another in higher plants is called as translocation of organic solutes.
What is a sink in fluid mechanics?
In sink flow, fluid moves radially inward (or absorbs fluid) towards a point known as sink, and fluid disappear at sink at a constant rate. Fig. b shows a sink flow, the point O is known as sink.
What is source and sink analysis?
Source-to-sink analysis is a novel method in sedimentary geology that includes investigating the entire sedimentary system from its ultimate upstream source in the continental realm to the ultimate sediment sink, most commonly on deep basin plains (Fig. 1; Sømme et al. 2009a, b).
What is translocation of water?
Water translocation is the transport of ions and molecules from soil (roots) to the desired location that occurs in xylem vessels as the result of the transpiration stream. 2. Transpiration is the evaporation of water from the leaves by mesophyll cells, also loss of water vapor through the stomata.
What is translocation for 7th class?
Translocation refers to the movement of nutrients from leaves to the other tissues in the plant. Water vapour is transported in transpiration. Sucrose is mainly transported in the translocation. Transpiration allows the inward movement of water in the xylem.
What is the process of translocation?
Translocation is the process within plants that functions to deliver nutrients and other molecules over long distances throughout the organism. The predominant nutrients translocated are sugars, amino acids, and minerals, with sugar being the most concentrated solute in the phloem sap.
What is source and sink flow in phloem translocation?
In this article we will discuss about the Flow of Source and Sink in Phloem Translocation. It is the long distance movement of organic substances from the source or supply end (region of manufacture or storage) to the region of utilization or sink. But the source and sink may be reversed depending on the season or need of the plants.
What is translocation in biology?
9.4 Translocation – a level biology student. Source to Sink: Translocation is the movement of organic compounds from where they are made at their source, to where they are required at their sink. It is an active process which can be used to transport phloem up or down the plant. Example sources of assimilates:
What is source source sink and assimilate in biology?
Source: Where an organic compound is made. Sink: Where an organic compound is required and used. Translocation: Movement of substances in the phloem from source to sink. Assimilate: A product of photosynthesis. Meristems: Meristematic tissue, a tissue which is actively dividing and growing.
How does sucrose sink in a mass transport system?
This increases sucrose concentration in companion cells, which creates a low water potential. Water osmoses into the companion cell, increasing turgor pressure. The water carrying the assimilates then moves to an areas of lower pressure – the sinks – in a mass transport system.
