BIOL 1134 - Lab Practical 2

Radicle or Primary Root

emergers from the seed and grows down

Secondary Roots

produced from primary root system

absorbs water and minerals, anchors the plant, adn stores food

Taproot system

large main root and smaller secondary roots branching from it

e.g. Carrot

Fibrous Root system

primary and secondary rotos are similar in size

Primary growth

roots and all primary tissues are produced by apical meristems

growth in length

Meristem

a localized area of cellular division

occurs at tips or roots and stems

Secondary growth

growth in grith resulting from nonapical meristems

Epidermis

outer layer of cell

covers the stem

coated with cutin

Cortex

inside the epidermis

Amylopasts

inside cells of cortex

starch-containing plastids

Endodermis

Inner layer of the cortex

affects water flow and regulates the flow of nutrients to the vascular tissue in the center of the root

Pericycle

immediately inside the endodermis

can become meristematic and produce secondary roots

Secondary roots

arise on the surface

Monocot root

bunched vascular bundles

one cotyledon

Eudicot

spread vascular bundles

two cotyledons

Buttercup root

a eudicot

Vascular Cylinder

the center of the buttercup root

composed of xylem and phloem

Xylem

transports water and minerals Ph

Pholem

transports water and most organic compounds in the plant

e.g. carbohydratesW

Tracheids

water-conducting cells in the xylem

long, spindle-shaped cells with thin areas or apertures called pits

Pits

Where cell walls of adjacent cells overlap

water moves through pits from one cell to the next

Vessel Elements

stacks of cylindrical cells with thin or completely open end-walls

water moves through in straight, open tubes

Tracheids and Vessel elements

water-conducting cells in the xylem

dead and hollow at maturity

Sieve cells and sieve tube members

conducting cells in phloem and alive at maturity

small, thin-walled, and arranged in bundles that alternate with the poles of xylem

shoot apical meristem

not covered by cap

the top of the root

Leaf Primordia

young leaves produced from apical meristem

Node

where leaves attach to stem

Axillary Bud

between the young leaf and stem - forms a branch or flower

Terminal bud

contains apical meristem at the stem tip

surrounded by bud scales

Leaf scares

occur at regularly spaced nodes along the length of the stem

Interndoes

portion of the stem between ndoes V

Vascular bundle scars

visible within leaf scars

Bud scale scares

distance between clusters or from a cluster to the terminal bud indicates the length of yearly growth

Cutin

wavy, waterproof substance that covers epidermis

Pith

center of the stem which also stores food

Collenchyma cells

three-four layers of cortex which are small, rectangular cells with unevenly thickened cell walls

support elongating regions of the plant

Sclerenchyma fibers

thick-walled cells just outside the phloem

Vascular cambium

tissue between xylem and phloem and each vascular bundle in eudicot stems

a secondary meristem

produces secondary growth of xylem and phloem

Wood

common name for secondary xylem

“grain” in wood

the change in density from the spring and summer wood

Function of secondary xylem in trees

conducting water and minerals and annual rings of the tree

What does the tree rings inform scientists about changes in climate

the size of the ring indicates the amount of water present in the environment, which shows climate change over many years

Tracheids in gymnosperms

small and help support the plant

Xylem of angiosperms

contain vessel elements and tracheids

vessel elements allow for better water flow (an adaptation)

Pine

gymnosperm

Oak

angiosperm

Bark

includes all tissues outside of the vascular cambium, including secondary pholem

Secondary phloem

consists of pyramidal masses of thick and thin walled cells

thin walled cells are conducting cells

Periderm

reconstructs ruptured epidermis tissue

Cork Cambium

produces cork cells, which reside in periderm. a secondary meristem

Lenticels

where gas exchange in peridermal tissues

look like small, white, horizontal, raised areas on stems of certain trees

Leaves consist of a _____ and ______

blade, petiole

Petiole

attach the leaf blade to the stem

Simple leaves

have one blade connected to the petiole

Compounds leaves

have several leaflets sharing on petiole

Palmate leaflets of compounds leaves

arise from a central area, as your fingers arise from palm

Pinnate leaflets

arise in rows along a central midline

Venation

arrangement of veins

Parallel veins

extern the entire length of the leaf with little or no crosslinking

Pinnately veined leaves

have one major vein from which other veins branch

Palmately veined

veins of vascular tissue in leaves each having branches

Phyllotaxis

arrangement of leaves on a stem O

Opposite phyllotaxis

refers to two leaves per node located on opposite sides of the stem

Alternate phyllotaxis

one leaf per node, with leaves appearing first on one side of the stem and then on the other

Whorled phyllotaxis

refers to more than two leaves per node

Stomata

small pores that allow for gas exchange

Palisade mesophyll

just below upper epidermis

closely packed cells that contain about 50 chloroplasts per cell

where most photosynthesis occurs

Spongy Mesophyll

cells with numerous intercellular spaces

below the palisade layers

Vegetative structures

roots, stems, and leaves

Reproductive structures

flowers, fruit, seeds

Cotyledons

seed leaves

Peduncle

flower stalk

Receptacle

the part of the flower stalk that bears the floral organs

located at the base of the flower

usually not large or noticeable

Sepals

the lowest whorls of structures

leaflike and protect the developing flowers

sepals collectively constitute the calyx

Petals

whorls of structure located inside and usually above the sepals

group of petals are - corolla

Androecium

male portion of the plant that rises above and inside the petals S

Stamen

contains filaments

located on anther

Anthers

contains the pollen grains

Microgametophytes of flowers

pollen grains

male gametes

Gynoecium

the female portion of the plant

consists of carpel, ovary, style and stigma

Ovules

located in the ovaries

Heterotrophic

consume organic molecules made by other organisms

Vetebrates

present backbone

invertebrates

lack backbone

Coelom

a body cavity

Molecular data

used to trace the evolutionary history of animals

Phylogenetic (evolutionary) tree

shows the evolutionary history of animals

Chordate

a few invertebrates and also vertebrates

Sponges

no tissue layers

asymmetrical or radially symmetrical

sessile (nonmobile)

reproduce asexually by budding or fragmentation

and reproduce sexually by producing egg and sperm

flagellated collar cells (choanocytes)

Parazoan

no tissue layers

Eumetazoa

two or more tissue layers

radial symmetry

two identical halves are obtained no matter how the animal is longitudinally sliced

Cnidarians

Eumetazoa

Radial symmetry

Ctenophores

Eumetazoa

radial symmetry

Bilateral symmetry

the animal has one plane of symmetry with a definite right half and left half

Protostomes

first opening of the embryo is mouth

Deuterostomes

first opening from the anus

Flatworms, rotifers, and roundworms are which pattern development

protostome development

Choanocytes

flagellated collar cells

keeps water moving through the pores into the central cavity and out of the osculum of sponge

also take in suspended food particles from the water and digest them for the benefit of all other cells