Just as humans have a circulatory system responsible for distributing nutrients, plants have a complex transport system. This system transports sap, a liquid substance essential for plant life. In vascular plants, two main types of sap are distinguished: raw sap y elaborated SAPBoth perform key functions and have very different characteristics. Throughout this article, you will learn in detail the differences between them, their functions, and how they are transported through the plant.
What is raw sap and elaborated sap
Sap is a circulating liquid in plants composed mainly of water, but also of mineral salts, amino acids, sugars and phytoregulatorsDepending on their origin and function, a distinction is made between raw sap and processed sap, each with specific characteristics and roles within the plant:
- Raw sap: It is formed in the roots when they absorb water and minerals from the soil. This aqueous mixture is transported to the leaves through the xylem.
- Elaborated SAP: It is the result of photosynthesis that takes place in the leaves. It contains sugars and other nutrients that are distributed throughout the phloem to various parts of the plant.
In this way, the raw sap provides the essential nutrients for photosynthesis, while the processed sap distributes the food and energy necessary for the growth of the plant, even reaching the roots.
Main functions of sap
Both raw sap and processed sap are crucial to the proper functioning of the plant. Each performs essential functions for plant survival and development.
- Essential Nutrient: The raw sap travels up the xylem and allows photosynthesis to take place in the leaves. The processed sap then exports nutrients and energy products to the rest of the plant.
- Thermal regulation: Transpiration through leaves and stems helps plants regulate their temperature, thus ensuring proper metabolic functioning.
- Defense against adverse conditions: In some cases, the sap of certain plants can act as a defense, as it may contain compounds that deter herbivores or minimize water loss in arid environments. Additionally, there are species that can store sap in their stems to use in times of drought.
Moreover, the sap is not only beneficial for the plant itself, but also has nutritional and medicinal applications for humans and animals. For example, the sap of some trees such as birch is traditionally used in medicine for its beneficial properties.
Differences between raw sap and processed sap
The differences between raw and processed sap are in their composition, transport and functions. Let's look at some of the main ones:
- raw sap: Its composition is formed almost exclusively by water and mineral salts. Its circulation is upward, from the roots to the leaves through the xylemRaw sap is crucial for preparing the raw material needed for photosynthesis.
- Elaborated SAP: Unlike raw sap, processed sap contains energy products, mainly sugars, and some other nutrients. Its movement is falling, being transported from the leaves to the other parts of the plant by means of the phloem.
These differences determine how the plant allocates and uses its resources to grow and develop.
Sap transport: mechanisms behind the process
The transport of sap along the plant follows different mechanisms depending on the type of sap:
- raw sap: The rise of water and nutrients from the roots to the leaves is facilitated by the xylemThe process is due to the suction generated by the Breathable grips in the leaves the cohesion of water, which allows it to counteract gravity.
- Elaborated SAP: With regards to elaborated SAP, the transportation process follows the pressure flow hypothesisThis mechanism involves osmosis and pressure changes in different parts of the plant, pushing the sap from the leaves to demanding areas such as fruits, roots or growing shoots.
Thanks to these mechanisms, plants maintain their metabolism and continue to develop, even under challenging conditions.
Understanding the complex sap transport system and how it enables plant life allows us to appreciate not only the biology of plants, but also the adaptations that allow them to survive in diverse environments.