BotanyRoots

Apoptosis

________ forms the conducting cells of xylem- the tracheary elements and we need living cells to transport materials (nucleic acids, mineral nutrients, etc) laterally in the plant.

Cortex

________ and epidermis sloughed Periderm consists of cork, cork cambium, and phelloderm.

Endomiycorrhizae

________ Are arbuscular inside the cells and in between the cells Progressivily stronger mutualistic symbioses between the fungi and the plant, depending on species and location.

Ectomycorrhizae

________- Surrounds but does not penetrate living cells in the roots Hyphae grow between the cells of the root epidermis and cortex, forming a characteristic highly branched network.

Endodermis

________ is the inner most layer of ground tissue, produced by the ground meristem.

Pericycle

________ makes the cork cambium, mature periderm has cork, cork cambium, and phelloderm.

Periderm

________ or bark Replaces epidermis as protective covering Originates from the lateral meristem called cork cambium.

Cuticle

________ is on the stem and on the leaves in primary growth, but not on the root.

Anticlinal

________ is perpindicular to the surface of the root.

Symplastic

________- moving through the plasma membrane from one membrane to another.

Water

________ is absorbed through the root hairs, passes through the cortex, and then into the xylem where it can be transported to other tissues and organs.

Periclinal

________ is parallel to the surface of the root.

Secondary root growth

________- Vascular cambium originates between primary phloem and metaxylem in sinuses of protoxylem poles from pericycle opposite protoxylem poles.

Protoxylem

________ occurs on outer projections of star- shaped core of xylem Metaxylem occurs in the middle.

Suberin

________ is a long chain lipid polymer, like cutin in the cuticle of leaves, both are hydrophobic and prevent movement of liquid into or out of cells.

Casparian strip

Endodermis- ________- ________ prohibits apoplastic movement of water and solutes and insures movement of water and solutes is controlled by living protoplast.

Endomycorrhizae

________- Fungal hyphae pemetrate cortical root cells and form highly branched arbuscules (arbusuclar mycorrhizae) Most common (80 % of vascular plants) not highly specific.

Apoplastic

________ is where the water moves through the spaces around cells by adhsion and capillary action of cellulose in the cell walls.

Lateral roots

________ originate by dedifferentiation and redifferentiation of the pericycle parenchyma cells.

Maturation

________ of the endodermis (with casparian strips) occurs prior to ________ of the xylem elements and development of root hairs.

Root cap

________- covers the apical meristem and is formed by divisions of cells at the tip in a forward direction.

Woody plants

________ require larger roots that are also woody.

Fungi

________ are heterotrophs, so plants are providing ________ with sugars and with suitable habitat.

Phloem cells

________ occupy sinuses between protoxylem poles.

Non functioning tracheary elements

________ occur in roots, and the ray cells sequester and transport nutrients from the dying vessel and tracheid elements inside to phloem outside for distribution throughout the plant.

Water moves

________ by osmosis From high concentration (soil) to low concentration (protoplasm of vascular cylinder) Active transport increases solute concentration in protoplast of roots Drives osmosis.

Pericycle

________- Originates from procambium Composed of parenchyma cells Redifferentiates into lateral roots Lies immediately inside endodermis Helps form root vascular cambium in secondary growth.

Suberin

________ is also found in periderm of stems (secondary growth)

Endodermis

________ is ground tissue.

Pericycle

________ is also responsible for secondary growth.

pericycle

So ________ is responsible for the formation of lateral roots.

Root cap

covers the apical meristem and is formed by divisions of cells at the tip in a forward direction

region of cell division

behind root cap and apical meristem

Region of cell elongation

behind region of cell division

Primary development

Apical meristem/region of cell division extends into and overlaps with region of cell elongation

Region of elongation is located

directly behind the root tip

Function of the Region of Elongation

where most of the growth or extension root length occurs

Region of maturation function

where root hairs occur

Sieve tube function

Extends furthest into the tip to provide sugars and energy for mitosis;the apical meristem is where cell division occurs

Primary root tissue systems

dermal tissue system (epidermis), Ground tissue system (cortex), vascular tissue system (vascular tissues, solid center in dicot, pith-like center of monocot)

Two major types

Endomycorrhizae Penetrate the root cells Most common-80% of vascular plants Not highly specific The fungal hyphae penetrate cortical cells of root form highly branched arbuscules (arbuscular mycorrhizae) Ectomycorrhizae Surrounds but does not penetrate living cells in the roots Hyphae grow between the cells of the root epidermis and cortex, forming a characteristic highly branched network

Endomycorrhizae

Fungal hyphae pemetrate cortical root cells and form highly branched arbuscules (arbusuclar mycorrhizae) Most common (80% of vascular plants) not highly specific

Ectomycorrhizae

Surrounds but does not penetrate living cells in the roots Hyphae grow between the cells of the root epidermis and cortex, forming a characteristic highly branched network

Root -cortex

Cortex occurs between epidermis and vascular cylinder

Symplastic

moving through the plasma membrane from one membrane to another

Root-endodermis

Innermost layer of cortex -Casparian strip Composed of hydrophobic suberin and sometimes lignin Lines the anticlinal surfaces of endodermis cell walls Prohibits apoplastic movement of water and solutes Solutes move through membrane into vascular cylinder controlled by living protoplast

Pericycle

Originates from procambium Composed of parenchyma cells Redifferentiates into lateral roots Lies immediately inside endodermis Helps form root vascular cambium in secondary growth

Secondary growth must originiate inside the endodermis to enjoy the protection of the casparian strips -the continuous cylender

to ensure uniform symplastic movement across the cells

Roots-secondary growth Root Secondary growth in large plants Additional anchorage Additional vascular tissue -Greater flow of nutrients Secondary growth involves

Creation of secondary xylem and phloem from a vascular cambium

Secondary root growth

Vascular cambium originates between primary phloem and metaxylem in sinuses of protoxylem poles from pericycle opposite protoxylem poles