C8: Mineral Nutrition (Pt 1) Flashcards
Plant ____ are essential components of higher plants, performing vital functions
like anchorage, water and nutrient absorption, and storage
root systems
A plant’s ___originates in the embryo
formed within the seed.
root
section of the embryo that is root tissue is called the ___.
radicle
root that forms from the embryonic radicle
is called the ___
primary root
embryonic shoot.
plumule
two types of root systems:
tap root or fibrous root.
is a persistent root that remains throughout the plant’s life; a strong primary root that grows downward the soil, acting as the central axis.
tap root
branch off irregularly from the tap root, responding to soil
conditions like moisture, nutrients, and soil structure.
Lateral (secondary) roots
type of root:
=grows perpendicular to the soil surface
= grow
parallel to the soil surface.
Primary (tap) root;
lateral roots
are thin, extensive, and web like making them effective at holding soil
in place and preventing erosion, especially in grasses
Fibrous root systems
are those that emerge from the main stem instead of the primary root.
Adventitious roots
two types of adventitious roots: (beans)
Basal roots
Hypocotyl roots
– emerge just above where the main stem transitions to the root, located at the
base of the main stem.
Basal roots
– form above the basal roots, emerging from the ___(the stem
portion above the root-shoot transition zone)
Hypocotyl roots; hypocotyl
Zones of the Root (4)
Root cap zone
Zone of cell division
Zone of elongation
Zone of maturation
– outermost region at the tip of the root, protecting the delicate growing cells
behind it as the root pushes through the soil. It secretes a slimy substance that lubricates the
root’s path and senses gravity, guiding the root’s direction.
Root cap zone
– located just behind the root cap, this zone contains meristematic cells
that rapidly divide to form new cells.
Zone of cell division
– in this region, cells produced in the cell division zone expand, pushing
the root further into the soil.
Zone of elongation
primarily responsible for the root’s vertical
growth and is where most of the increase in root length occurs.
root elongation
– located above the elongation zone, cells here differentiate into
specialized cells for functions like nutrient absorption, water transport, and food storage; Root hairs also develop
Zone of maturation
are tiny hair-like structures that increase the surface area for water and nutrient
uptake. They are found near the root tip and are crucial for efficient absorption.
Root hairs
serve as the
primary interface between plants and the soil environment
roots
Roots also release ___—organic compounds such as
acids, sugars, and amino acids—into the surrounding soil, modifying its chemistry to improve
nutrient availability
exudates
relationship between mycorrhizal fungi and plants; symbiotic and mutualistic interaction
Mycorrhizal Associations
In this association, fungi colonize plant roots,
forming extensive networks that penetrate the soil, facilitating the uptake of nutrients and water
for the host plant. The fungi benefit by receiving essential carbon compounds from the plant,
Mycorrhizal Associations
provide plants with several vital advantages, including enhanced
nutrient acquisition, improved tolerance to abiotic stresses (such as drought and salinity), and
protection against soil-borne pathogens.
Mycorrhizal fungi
, the most common
type of mycorrhizae, interact with about 80% of terrestrial plant species, including many
agricultural crops, significantly improving phosphorus, calcium, magnesium, and iron uptake.
Arbuscular mycorrhizal fungi (AMF)
two types of mycorrhizae
Arbuscular Mycorrhizae (AM)
Ectomycorrhizae (ECM)