Unit 3 - Plant Anatomy Lecture (ch. 26, 19, 12)

Describe determinant growth and what organisms it occurs in

Cells that differentiate and form tissues with a pre-programmed body plan, stops after a certain age (common in animals)

Describe indeterminant growth and what organisms it occurs in

Areas of rapidly dividing undifferentiated cells throughout life with a feature called meristems, without a pre-programmed body plan (common in plants).

What are the two lateral meristems that causes secondary growth?

vascular cambium and cork cambium

Describe vascular cambium.

Lateral meristems that produces secondary xylem inward and secondary phloem outwards

Describe cork cambium (phellogen)

Lateral meristems that produces cork (phellem) and phelloderm, which together forms the periderm

What are the two types of initials that form meristematic cells?

Fusiform initials and ray initials

Describe fusiform initials

Vertically elongated meristematic cells in the vascular cambium that gives rise to the axial system of secondary vascular tissues

Describe ray initials

Cuboidal meristematic cells in the vascular cambium that gives rise to the radial system for horizontal transport

Describe anticlinal division

Cell divisions perpendicular to the organ surface that allow the vascular cambium to expand in circumference

Describe periclinal division

Cell divisions parallel to the organ surface produce secondary xylem inwards and secondary phloem outwards

Describe the wood dynamics of sapwood

Outer, youngest layers of secondary xylem containing living parenchyma cells responsible for water and mineral conduction

Describe the wood dynamics of heartwood

Inner, oldest layers of secondary xylem with no living cells that stores reserves, accumulates resins, and provide structural strength

Describe the wood dynamics of early wood (spring wood) vs late wood (summer wood)

Early wood has larger, wider cells formed early in the growing season for rapid water transport, while late wood has smaller, thick-walled cells formed later in the season for structural support.

Describe the difference of Ring-Porous Wood vs. Diffuse-Porous Wood

Ring-porous wood has large vessels concentrated in early wood (e.g., oak); diffuse-porous wood has vessels distributed evenly across the growth ring

Describe periderm

Protective tissue layer replacing the epidermis in woody stems, consisting of cork, cork cambium, and phelloderm

Describe bark

All plant tissues located completely outside the vascular cambium (includes living and dead phloem plus periderm layers)

Describe lenticels

Porous, unregulated aerating openings in woody bark that replace stomata to allow gas exchange

Describe systematics

Scientific study of biological diversity and evolutionary history, combining taxonomy and phylogeny

Describe cladogram

A branching diagram that represents an estimate of phylogenetic relationships based on shared derived characteristics

Describe the difference between Homologous vs. Analogous Features

Homologous features share a common evolutionary origin, while analogous features share a similar function but different origins

What is the binomial system of nomenclature

A formal naming system created by Carl Linnaeus consisting of a capitalized Genus name and a lowercase specific epithet

Describe the features of monocots vs dicots

• Monocots: scattered vascular bundles, parallel leaf venation, floral parts in multiples of 3, one cotyledon, fibrous roots, absent secondary growth.

• Dicots: ring-arranged vascular bundles, net leaf venation, floral parts in multiples of 4 or 5, two cotyledons, taproot, secondary growth present in woody plants.

Describe the difference of complete vs incomplete flowers

Complete flowers contain all four floral whorls (sepals, petals, stamens, and carpels); incomplete flowers lack one or more whorls

Describe the difference between monoecious and dioecious plants

Monoecious plants have separate male and female flowers on the same individual plants; dioecious plants have them on separate individual plants

For seed development, a mature ovary turns into a BLANK

fruit

For seed development, a mature ovule turns into a BLANK

seed

Describe the difference of a perfect flower vs imperfect flower

Perfect flower contains both androecium (stamens) and gynoecium (carpels), while an imperfect flower lacks one of these parts

Describe the fertile parts of a flower and what organs are featured in each part

Stamens (male organs: anther and filament); Carpels (female organs: stigma + style + ovary)