transport of food and minerals in plants Flashcards
what is transport in plants
transport in plants refers to the process of carrying substances like food, water, and minerals from one part of the plant to another.
what is diffusion
diffusion is the movement of molecules (of gas, liquid, or solid) from an region of higher concentration to a region of lower concentration until they are spread out evenly.
what is xylem ?
xylem is a vascular tissue, that facilitates the upward movement of water through channels known as xylem elements. xylem is a complex tissue, consisting of parenchymatous cells (living thin-walled cells) and sclerenchymatous (dead thick-walled cells) cells.
what are the parts of xylem?
- tracheid: non-living, elongated cell with tapering ends.Its cell walls are highly thickened with lignin, except at certain circular spots known as pits.
- vessel: non- living cell with lignified walls. elongated, cylindrical shaped cell placed one above the other vertically. the cell walls dissolve partially or completely forming one continuous channel.
-xylem parenchyma: living, thick-walled cells that perform the function of storage.
-xylem fibers: non-living, thick-walled cells that provide mechanical support to the plant.
what are the parts of phloem?
-sieve tubes are the main conducting element in the phloem. They are cylindrical, elongated and thin-walled cells arranged in vertical rows. The end wall of ach sieve tube is perforated.the perforated walls are known as sieve plates. The pores r perforations are known as sieve areas. these perforations allow food materials to pass through easily. At maturity, sieve cells lack a nucleus but remain living because of companion cells.
-companion cells : companion cells are mainly associated with sieve cells and help in conducting food.they have dense cytoplasm and prominent nuclei.
-phloem parenchyma:thin-walled, living parenchymatous cell, it performs the function of storage.
-phloem fibers: sclerenchymatous, elongated, thick-walled dead and lignified cells.They provide mechanical support to the plants.
what is osmosis?
osmosis is the movement of water molecules from a region of higher concentration to a region of lower concentration through a semi-permeable membrane .
what is ascent of sap?
-the cell membrane of a plant is a semi-permeable membrane
-the cell sap inside the vacuole is a strong solution that contains high concentration of solute
-water passes into the root hair cell by osmosis.
-the concentration of sap in the vacuole gets weaker as the water concentration increases
-hence, the water passes into the next cell through osmosis
-the process continues until the water reaches the xylem tissue in the root, From xylem, the water moves upward against gravity due to the transpirational pull.
what is transipiration?
transpiration is the loss of water in the vapour form from the leaves in to the atmosphere.
what is the importance of transpiration?
-results in the transport of water and minerals
-produces a cooling effect in the plants which help prevent the sun from damaging the delicate leaf cells.
what are the factors affecting transpiration?
-intensity of light
-temperature
-humidity
-the amount of available soil water
-wind velocity (transpiration and wind velocity are inversely proportional.
what is root pressure?
root pressure id the pressure under which water moves from the living cells of root into the xylem.
-developed due to the upward flow of water as a result of the pressure developed in the roote due to the accumalation of water absorbed by them.
what is active transport?
-movement of water molecules across a semipermeable membrane against a concentration gradient using energy is known as active transport.
what minerals are needed by plants?
-16 essential elements
-macro-nutrients: carbon, hydrogen, oxygen
-micro-nutrients: chlorine. copper ,boron
