C8: Mineral Nutrition (Pt 1)

Question 1

Plant ____ are essential components of higher plants, performing vital functions
like anchorage, water and nutrient absorption, and storage

Answer 1

root systems

Question 2

A plant’s ___originates in the embryo
formed within the seed.

Answer 2

root

Question 3

section of the embryo that is root tissue is called the ___.

Answer 3

radicle

Question 4

root that forms from the embryonic radicle
is called the ___

Answer 4

primary root

Question 5

embryonic shoot.

Answer 5

plumule

Question 6

two types of root systems:

Answer 6

tap root or fibrous root.

Question 7

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.

Answer 7

tap root

Question 8

branch off irregularly from the tap root, responding to soil
conditions like moisture, nutrients, and soil structure.

Answer 8

Lateral (secondary) roots

Question 9

type of root:

=grows perpendicular to the soil surface
= grow
parallel to the soil surface.

Answer 9

Primary (tap) root;
lateral roots

Question 10

are thin, extensive, and web like making them effective at holding soil
in place and preventing erosion, especially in grasses

Answer 10

Fibrous root systems

Question 11

are those that emerge from the main stem instead of the primary root.

Answer 11

Adventitious roots

Question 12

two types of adventitious roots: (beans)

Answer 12

Basal roots
Hypocotyl roots

Question 13

– emerge just above where the main stem transitions to the root, located at the
base of the main stem.

Answer 13

Basal roots

Question 14

– form above the basal roots, emerging from the ___(the stem
portion above the root-shoot transition zone)

Answer 14

Hypocotyl roots; hypocotyl

Question 15

Zones of the Root (4)

Answer 15

Root cap zone
Zone of cell division
Zone of elongation
Zone of maturation

Question 16

– 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.

Answer 16

Root cap zone

Question 17

– located just behind the root cap, this zone contains meristematic cells
that rapidly divide to form new cells.

Answer 17

Zone of cell division

Question 18

– in this region, cells produced in the cell division zone expand, pushing
the root further into the soil.

Answer 18

Zone of elongation

Question 19

primarily responsible for the root’s vertical
growth and is where most of the increase in root length occurs.

Answer 19

root elongation

Question 20

– 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

Answer 20

Zone of maturation

Question 21

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.

Answer 21

Root hairs

Question 22

serve as the
primary interface between plants and the soil environment

Answer 22

roots

Question 23

Roots also release ___—organic compounds such as
acids, sugars, and amino acids—into the surrounding soil, modifying its chemistry to improve
nutrient availability

Answer 23

exudates

Question 24

relationship between mycorrhizal fungi and plants; symbiotic and mutualistic interaction

Answer 24

Mycorrhizal Associations

Question 25

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,

Answer 25

Mycorrhizal Associations

Question 26

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.

Answer 26

Mycorrhizal fungi

Question 27

, 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.

Answer 27

Arbuscular mycorrhizal fungi (AMF)

Question 28

two types of mycorrhizae

Answer 28

Arbuscular Mycorrhizae (AM) Ectomycorrhizae (ECM)

Question 29

form intracellular associations with plant roots, penetrating the root cells and creating specialized structures called ___(tree-like formations) within the root cortex cells.

Answer 29

Arbuscular Mycorrhizae (AM); arbuscules

Question 30

this type of mycorrhizae form an __ or __ around the roots, without penetrating root cells. They establish a network called the ___, which extends between the root cortex cells, allowing nutrient transfer.

Answer 30

Ectomycorrhizae (ECM) external sheath or mantle; Hartig net;

Question 31

is the narrow region of soil that directly surrounds and is influenced by plant roots.

Answer 31

rhizosphere

Question 32

It is a highly dynamic area where root secretions (exudates) interact with soil particles, nutrients, and microorganisms, creating a microenvironment that differs chemically and biologically from the bulk soil.

Answer 32

rhizosphere

Question 33

___for iron, __ for phosphorus

Answer 33

coumarins; organic acids

Question 34

Nutrient Acquisitions (3)

Answer 34

Phosphorus Solubilization Iron Acquisition Nitrogen Fixation

Question 35

Certain rhizosphere microbes produce ___ and ___that release phosphorus from soil minerals, making it accessible to plant roots.

Answer 35

organic acids (like oxalate and citrate); phosphatases

Question 36

microbes example: Phosphorus solubilization= Nitrogen fixation=

Answer 36

Phosphorus solubilization= Burkholderia Nitrogen fixation= Rhizobium

Question 37

Some microbes, particularly ___ bacteria, help plants access this nutrient by producing compounds like ___—small molecules that bind and transport iron.

Answer 37

iron-reducing; siderophores

Question 38

recruit iron-reducing bacteria, thus improving iron uptake during deficiency periods

Answer 38

coumarins

Question 39

Abiotic Stress Rhizosphere microbes can produce ___(e.g., auxins, cytokinins, gibberellins) that regulate plant growth and enhance stress resilience. For instance, microbes like ____ produce hormones that stimulate root growth and improve tolerance to drought, salinity, and other abiotic stresses.

Answer 39

phytohormones; Pseudomonas and Bacillus strains

Question 40

___ is one whose absence prevents a plant from completing its life cycle.

Answer 40

Essential element

Question 41

classification of essential elements

Answer 41

macronutrients or micronutrients,

Question 42

The first group of essential elements are part of the ____ of the plant.

Answer 42

organic (carbon) compounds

Question 43

The second group of essential elements is important in __ reactions or in maintaining ___

Answer 43

energy storage; structural integrity.

Question 44

The third group of essential elements is present in plant tissue as either ____Of particular importance are their roles as ___

Answer 44

free ions or ions bound to substances. ; enzyme cofactors.

Question 45

The fourth group of essential elements has important roles in reactions involving ____

Answer 45

electron transfer.

Question 46

Group 1: Nutrients that are part of carbon compounds. (2)

Answer 46

Nitrogen sulfur

Question 47

– a constituent of proteins (amino group) and nucleic acids (nitrogenous bases).

Answer 47

Nitrogen

Question 48

– it is a component of some amino acids such as cysteine and methionine.

Answer 48

Sulfur

Question 48

Group 2: Nutrients that are important in energy storage or structural integrity. (3)

Answer 48

Phosphorus Silicon Boron

Question 48

– Component of nucleic acids and phospholipids as phosphate group. Has a key role in reactions that involve ATP.

Answer 48

Phosphorus

Question 48

– Contributes to cell wall mechanical properties, including rigidity and elasticity

Answer 48

Silicon

Question 49

– Constituents of cell walls; involved in cell elongation.

Answer 49

Boron

Question 50

Group 3: Nutrients that remain in ionic form (6)

Answer 50

Potassium Calcium Magnesium Chlorine Manganese Sodium

Question 51

– Required as a cofactor for more than 40 enzymes such as pyruvate kinase in glycolysis.

Answer 51

Potassium

Question 52

– Constituent of the middle lamella of cell walls. Required as a cofactor by some enzymes. Acts as a second messenger in metabolic regulation.

Answer 52

Calcium

Question 53

– Required by many enzymes involved in phosphate transfer. Constituent of the chlorophyll molecule.

Answer 53

Magnesium

Question 54

– involved in ionic balance during the photolysis of water.

Answer 54

Chlorine

Question 55

– Required for activity of some enzymes such as kinases, and peroxidases.

Answer 55

Manganese

Question 56

– Involved in the process of C4 and CAM cycle specifically by maintaining osmotic balance and overall cellular homeostasis.

Answer 56

Sodium

Question 56

Group 4: Nutrients that are involved in electron transfer (5)

Answer 56

Iron Zinc Copper Nickel Molybdenum

Question 57

– Constituent of cytochromes involved in photosynthesis.

Answer 57

Iron

Question 58

– Constituent of many enzymes in various biochemical processes which helps the plant grow.

Answer 58

Zinc

Question 59

– Component of phenolase and plastocyanin involved in oxidation of phenolic compounds which affect color of fruits and vegetables, and in transferring electrons between cytochrome b6f and Photosystem I, respectively.

Answer 59

Copper

Question 60

– In nitrogen-fixing bacteria, __ is a constituent of hydrogenases.

Answer 60

Nickel

Question 61

– Cofactor of enzymes nitrogenase which is involved in fixing atmospheric nitrogen (N₂) into ammonia (NH₃).

Answer 61

Molybdenum

Question 62

– initial phase where plants absorb essential nutrients. This step involves the uptake of minerals in their ionic form (e.g., nitrate, potassium, magnesium) along with water.

Answer 62

Nutrient Acquisition

Question 63

– follows acquisition and involves the transformation of these absorbed nutrients into forms that the plant can use for growth and development.

Answer 63

Nutrient Assimilation

Question 64

– main organ for nutrient and water uptake; – primary site for photosynthesis

Answer 64

Roots; Leaves

Question 65

– short lived tubular extensions of epidermal cells, where the water and nutrients first enter the plant; increase surface area of root

Answer 65

Root hairs

Question 66

Nitrogen and other elements absorbed by roots are used in ___to form proteins and other compounds.

Answer 66

leaves