External and Internal Structure of Stem Flashcards by Max Sy

GENERAL FUNCTION OF
STEM

Provide pathways for the:
§ Movement of water and
dissolved minerals from the
roots into the leaves
§ Food synthesized in leaves
to move into roots

How well did you know this?

Not at all

Perfectly

PRIMARY FUNCTION OF
STEM

§ Support and orient the leaves
§ Conduct water and minerals
§ Bear flowers and fruits

How well did you know this?

Not at all

Perfectly

SECONDARY FUNCTION
OF STEM

§ Storage
§ Perennation
§ Vegetative propagation
§ Photosynthesis
§ Protection
§ Climbing

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

area of a stem where a leaf
or leaves are attached

Node

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

the stem region
between nodes

Internodes

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

a structure that has
the potential to form a lateral shoot
or branch

Axillary bud

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

aka: terminal bud, is
located near the shoot tip and
causes elongation of a young shoot

Apical bud

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

helps to maintain
dormancy in most non-apical buds

Apical Dominance

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

structure that
permits the passage of
gas inward and outward

Lenticels

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

characteristic
scar on stem axis made
by leaf abscission

Leaf scar

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

small
modified leaves for
protection from
desiccation

Bud scales

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

a stem’s primary
growing point. It can
either be leaf buds or
flower buds.

Bud

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

scars left
from the removal of bud

bud scar

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

an
immature lead of the
shoot

Leaf primordium

How well did you know this?

Not at all

Perfectly

EXTERNAL STEM
MORPHOLOGY

portion of the
internodes above the node and it is
made up of actively dividing cells
responsible for the elongation of the
monocot stem

Intercalary meristem

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

The outer group consisting of one or
more peripheral cell layer is known as
the ______. These cells divide
perpendicular to the surface of the
shoot apex.

tunica

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

The ______ lies below the tunica and
initially has a single layer of cells. Its cells divide perpendicular to the
surface of the shoot apex and parallel
to the surface of the shoot apex.

corpus

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

A shoot apical meristem is a _____-____ mass of dividing cells at the
shoot tip

dome-shaped

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

Leaves develop from leaf primordia
along the sides of the?

apical meristem

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

This develop from
meristematic cells left at the bases of
leaf primordia

Axillary buds

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

Primary Meristems:

: the outermost
layer of cells. It develops into
epidermis (a primary tissue
that covers and protects all
underlying tissues, prevents
excessive water loss and
allows exchange of gases
necessary

§ Protoderm

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

Primary Meristems:

: comprises
the greater portion of
meristematic tissue of the
shoot tip.

§ Ground Meristem

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

Primary Meristems:
§ Primary tissues forming the
ground meristem are:

: in the very center of
stem

§ Pith

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS
ORGANIZATION

§ Primary tissues forming the
ground meristem are:

: in a cylinder just
beneath the epidermis and
surrounding the vascular
tissues. Sometimes pith
and cortex are connected
by pith rays

§ Cortex

How well did you know this?

Not at all

Perfectly

SHOOT APEX AND ITS ORGANIZATION Primary Meristems: give rise to primary vascular tissues namely: primary phloem and primary xylem

Procambium cells

STEM ANATOMY are perpetually embryonic tissue and allow for indeterminate growth

MERISTEMS

STEM ANATOMY are located at the tips of roots and shoots and at the axillary buds of shoots. Apical meristems elongate shoots and roots, a process called primary growth

APICAL MERISTEMS

STEM ANATOMY § Stems usually undergo primary growth which results in the formation of primary tissues. These include the:

§ Epidermis § Ground tissue § Primary vascular tissues (primary xylem and primary phloem)

This term is applied to the part of the stem that includes the primary vascular tissues, pith and pith rays. The primary plant body is composed of the above primary tissues.

stele

outermost single layered, covered with cuticle, bears multicellular hairs, and offers protective function

epidermis

vascular tissues? (6 items)

§ Phloem § Vascular cambium § Xylem § Cortex § Pith § Pith rays

: conducts food

phloem

produces secondary phloem and secondary xylem

vasculart cambium

conducts water and mineral salts, and gives strength to stem

xylem

stores food and in young stems, manufactures food, strengthen and protects

cortex

Stores food

pith

store food, conduct water, mineral salts and food radically

pith rays

Secondary growth occurs in stems and roots of woody plants but rarely in?

leaves

The Secondary plant body consists of the tissues produced by the vascular cambium and cork cambium. Secondary growth is characteristic of __________ and many edicts, nut not monocots.

gymnosperms

These tissue layers for the PERIDERM

phellem phellogen pheloderm

The outermost layer of periderm, consisting of cork cells.

phellem

immediately into the inner of perriderm, also known as the cork cambium, consisting of flattened dividing cells

phellogen

The third layer of periderm, few cell layers in thickness

pheloderm

a cylinder of meristematic cells one cell layer thick. It develops from undifferentiated parenchyma cells

vascular cambium

In _____ _______, the vascular cambium appears as a ring of initials. The initials increase the vascular cambium’s circumference and add secondary xylem to the inside and secondary phloem to the outside.

cross section

this accumulates as wood and consists of tracheid, vessel elements (only in angiosperms) and fibers

secondary xylem

formed in the spring, has thin cell walls to maximize water delivery

early wood

formed in late summer, has thick-walled cells and contributes more to stem support

late wood

In _________ ______, the vascular cambium of perennials is dormant through winter.

temperate regions

these are visible where late and early wood meet, and can be used to estimate a tree’s age

tree rings

the analysis of tree ring growth patterns and can be used to study past climate change

Dendrochronology

As a tree or woody shrub ages, the older layers of secondary xylem, the _________, no longer transport water and minerals.

heartwood

The outer layers, known as _______, still transport materials through the xylem

sapwood

Older secondary phloem _______ ___ and does not accumulate

sloughs off

gives rise to the secondary plant body’s protective covering, or periderm

cork cambium

consists of the cork cambium plus the layers of cork cells it produces

periderm

consists of all the tissues external to the vascular cambium, including secondary phloem and periderm

bark

in the periderm allow for gas exchange between living stem or root cells and the outside air.

lenticels

A plant can grow throughout its life; this is called

INTERMEDIATE GROWTH

Some plant organs cease to grow at a certain size; this is called

DETERMINATE GROWTH

- complete their life cycle in a year or less Ex: Cereals and Legumes

annuals

- require two growing seasons Ex: Onion and Carrots

biennials

live for many years Ex: Shrubs and Trees

perennials

SPECIALIZED STEMS

RHIZOME RUNNERS AND STOLONS TUBERS BULBS CORMS CLADOPHYLLS/PHYLLOCLADE TENDRILS

§ horizontal stems that grow below ground with short internodes and bears scale-like leaves. § Ex: ginger, cogon grass

rhizome

horizontal stems that grow above ground, generally along the surface. Ex: strawberry

runners

like runners but are produced beneath the surface of the ground and tend to grow in different directions but usually not horizontally. Ex: potato

stolons

a thick under ground storage stem, usually not upright bearing outer buds but lack protective scales.

tubers

§ consist of small amount of vertical stem and a massive quantity of thick, fleshy storage leaves. § Most of them consist of concentric rings of scales attached to a basal plate

bulbs

§ resemble bulbs but differ from them in being composed almost entirely of stem tissue, except for a few papery, scalelike leaves sparsely covering the outside. § Consist of one or more internodes with at least one growing point. § Formed from a swollen bases of stems

corms

The entire shoot is flattened and leaf like

CLADOPHYLLS/PHYLLOCLADE

These are specialized stems in grapes but are modified leaves or leaf parts in plants like peas and cucumbers

tendrils

a stress-related disease that affects sweet gum, oak, elm and willow trees. The disease is caused by a microorganism that ferments the sap that seeps or bleeds from cracks and wounds in the bark. The result is a white, frothy ooze that has a fermenting odor similar to beer.

White Flux or Alcoholic flux

Filled with nutrients and minerals, ___ is the blood of a tree. It carries energy out into the branches when new buds are forming in spring-time.

sap

Because sap is like the engine that keeps nourishing ingredients running throughout the tree, small amounts of sap may ooze all year from pines. Usually that happens after they're ____, when they begin budding or as the seasons change. Typically, you'll see the most sap flow in spring and early summer.

pruned

The pine produces excessive amounts of sap to protect itself against the?

bark beetle