Bio Lab - Chapters 6-10

Angiosperms

Vascular plants that have the ovules and seeds enclosed in an ovary

Form the embryo and endosperm by double fertilization

Also called a flowering plant

Produce seed enclosed in a fruit, which was originally an ovary of the flower

Anther

The part of a stamen of the flower that produces and contains pollen and is usually borne on a filament

Apical Meristem

Embryonic tissue regions forming new cells at the tips of roots and shoots

Archegonium

Gametangium that produces an egg

Carpel

The ovule-bearing structures in an angiosperm differentiated into an ovary, style, and stigma, the innermost whorl of a flower

Double Fertilization

Fertilization characteristic of angiosperms in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm

Embryo

The young sporophyte of a seed plant, usually comprising a rudimentary plant developing within a seed

Endosperm

A nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus

Fertilization

In seed plants, the process following pollination, the process of union of two gametes

Filament

The anther-bearing stalk of a stamen

Fruit

The usually edible reproductive body of a seed plant, a mature ovary of the flower

Houses the seeds and important for dissemination of those seeds

Gymnosperms

A group of vascular plants that produce naked seeds not enclosed in an ovary (not covered by a protective outer structure)

Heterosporous

The production of microspores and megaspores, as in seed plants

The production of two different types of spores

Homosporous

The production of spores of only one kind by various plants (such as the mosses and ferns)

Indeterminate Growth

Plant growth in which the main stem and roots continue to elongate indefinitely without being limited

Integument

Outer protective layers (one in gymnosperms, two in angiosperms) of cells surrounding the ovule

Develop into the seed coat

Megagametophyte

The female gametophyte produced by a megaspore

Megasporangia

A sporangium that contains megaspores

Megaspores

A spore in heterosporous plants giving rise to female gametophytes and usually larger than a microspore

Megasporocyte

Megaspore mother cell that divides by meiosis to produce a megaspore

Microgametophyte

Pollen, the male gametophyte produced by a microspore

Microsporangia

A sporangium that contains only microspores

Microspores

Haploid spores in heterosporous plants arising from meiotic division of the microsporocytes in microsporangia and give rise to male gametophytes

Microsporocyte

A microspore mother cell giving rise to microspores after meiosis

Nucellus

The central and chief part of a plant ovule that encloses the female gametophyte

Remnant of the megasporangium housed within the seed coat and is used as nutrient for the growing embryo

Ovary

Enlarged basal portion of the carpel, the female organ of a flower

The ovary contains ovules which develop into seeds upon fertilization

The ovary matures into the fruit as seeds develop

Ovules

Compartments in the ovary within which eggs develop and are fertilized

The ovules will develop into the outside covering of the seed

Ovulate Cone

Female pine cone

Petals

One of the modified often brightly colored leaves of the corolla of a flower

Pollen Cone

Male pine cone

Pollen Grain

The male gametophyte of a seed plant, produced by mitotic divisions of the haploid microspores

Can be transferred to the female gametophytes before sperm cells are produced

No need for water for sperm to reach the egg

Pollen Tube

A tube that is formed by a pollen grain and conveys the sperm nuclei to the embryo sac of an angiosperm or the archegonium of a gymnosperm

Pollination

The transfer of pollen from an anther to the stigma in angiosperms or from the microsporangium to the micropyle in gymnosperms

Primary Growth

Vertical growth of plants in roots and shoots (the apical meristems) as a result of cell division, lengthening stems to that plants grow taller, enabling leaves to reach sunlight and lengthening of roots for more absorption of water and minerals

Receptacle

The end of the flower stalk upon which the floral organs are borne

Where modified leaves of the flower area are attached together

Roots

Parts of plants that function to keep the plant anchored to the soil and to absorb water and minerals

Scale

Modified leaves or perhaps modified branches of the male or female pine cone

Seedling

A young plant, especially one raised from seed and not from cutting

Seed Coat

The outer tissues of the ovule that harden, covering and protecting the seed

Seeds

The fertilized ripened ovule of a flowering plant containing an embryo and capable normally of germination to produce a new plant

The plant embryo is packaged in a protective case with a supply of food

Secondary Growth

An increase in the thickness/girth of the shoots and roots of a vascular plant as a result of the formation of new cells in the cambium

Involves the production of wood

Sepal

Modified leaves at the base of the flower

Usually green and enclose the flower before it opens

Shoots

Parts of plants that function to bring the photosynthetic organs (leaves) closer to sunlight and to absorb CO₂ from the atmosphere for photosynthesis

Stamen

A microsporophyll of a seed plant

The pollen-producing male organ of a flower that consists of an anther and a filament

Stigma

Apical part of the carpel of a flower which receives the pollen grains

Strobilus

The cone of a pine

Style

The elongated part of the carpel bearing a stigma at its apex

Zygote

A cell formed by the union of two gametes - eggs and sperm

Roots

Generally underground and function in anchorage and absorption of water and minerals

Leaves

Composed of a petiole for attachment and a blade, which is specialized to create a large surface area for absorbing light and exchanging gases for photosynthesis

Node

Site on stem where a leaf emerges

Bud

Underdeveloped tissue that may give rise to new leaves, branches, or flowers

Apical Meristems

Regions of cell division at the tip of a plant's stems and roots

Meristematic Cells

The cells undergoing mitosis at the root tip

Cotyledons

Serve as the energy source for germination in seeds

Primordia

Structures that are newly developed and not fully formed

Simple Tissue

Consists of one cell type

Complex Tissue

Consists of more than one cell type

Primary Cell Wall

Relatively thin cellulose framework

Has the ability to expand during the growth of the cell

Secondary Cell Wall

Composed of multiple layers of cellulose fibers

Embedded with a substance called lignin

Parenchyma

Basic cell type for vascular plants

Alive at maturity

Collenchyma

Functions in support of soft or growing stems and leaves

Alive at maturity

Sclerenchyma

More specialized to provide support and structure to the plant

Come in 2 shapes: sclereids and fibers

Dermal Tissue Systems

Complex tissues forming the outer, protective covering of the plant

Outer covering may be composed of a single layer of epidermis

Often protected by a cuticle

Cuticle

Waxy covering that helps to reduce evaporation of water from the plant surface

Protects dermal tissue systems

Stomata

Openings in the epidermis and cuticle that allow gases in and out of the plant

Openings flanked by guard cells

Guard Cells

Open or close the stomata in response to conditions such as light or water loss

Vascular Tissue Systems

Complex tissue systems responsible for internal transport in plants

Two types: xylem and phloem

Xylem

Responsible for transporting water and minerals from the roots to the leaves

Phloem

Transports the sugars that are produced by photosynthesis to the rest of the plant

Ground Tissue System

Located internal to the dermal tissue on the edge of a plant and surrounding the vascular bundles

Includes several cell types that support, store, and metabolize

Monocot

Seeds have one cotyledon

Examples include corn, onions, palms, tulips, lilies, and grass

Leaves tend to have veins in a parallel pattern

Dicot

Seeds have 2 cotyledons

Examples include trees, shrubs, beans, peas, geraniums

Leaves have branching veins

Endodermis

Innermost layer of the cortex

A single layer of cells that surround the vascular cylinder

Epidermis

Single layer of cells on both surfaces of the leaf

Mesophyll Layer

Middle of the leaf between the layers of epidermis

Contains the photosynthetic parenchyma cells

Cortex

Region from the vascular cylinder outward

Herbaceous Dicot Stem

Soft green stem, as opposed to a woody stem

Procambium

Thin layer of cells sandwiched between the xylem and phloem in each vascular bundle

Pith

Region in the center of the ring of vascular bundles

Cortical Parenchyma

Cells found in the cortex

Pith Parenchyma

Cells found in the pith

Vascular Cambium

Continuous cylinder of meristematic cells found between the xylem and the phloem

Thin layer of cells

Growth Rings

Result of differential growth of xylem at different times of the year