Lab practical 2

heterotrophic

cosume organic molecules made by other organisms

vertebrates

have a backbone

invertebrates

lack a backbone

coelom

true body cavity

asymmetry

has no particular symmetry

radical symmetry

wheel symmetry

bilateral symmetry

one plane of dymmetry with a definite right and left half

protostomes

pattern of development which first opening of embryo forms the mouth

deuterostomes

first opening forms the anus

Sponges

(porifera)

sessile filter feeders

sessile

nonmobile

collar cells (choanocytes)

keeps water moving through the pores into the central cavity

osculum

main excurrent opening in sponges

spicules

fine projections over the body and especially encircling the osculum

polyp

basic body of a cnidarian

mouth directed upward

sessile

Medusa

basic body of a cnidarian

mouth is directed downward

(jellyfish)

polymorphism

life cycle that involves two forms

gastrovascular cavity

single opening that is used as both an entrance for fodd and an exit for wastes

cnidocytes

specialized stinging cells

nematocyst

fluid filled capsule in cnidocyte which contains a long spirally coiled hollw thread. Traps and/ or stings prey

hermaphroditie

means they posses both male and female sex organs

(planarians

flame cells

excretory organs that collect fluids from inside the body and send them via a tube to an excretory pore

(planarians)

ladderlike

nervous system contains a brain and lateral nerve cords connect by transverse nerves

(planarians)

scolex

head

proglottids

segments of the body

mature ones detach and pass out with the host’s feces(scattering fertilized eggs.)

(planarians)

radicle (young primary root)

root that emerges from the seed and grows down

secondary roots

these forms a root system that absorbs water and minerals, anchors the plant and stores food

taproot system

large main root and smaller secondary roots

fibrous root system

primary and secondary roots are similar in size

primary growth

produced by apical meristems

growth in length

produces herbaceous tissue (nonwoody)

apical meristems

localized area of cellular division

occur at the tips of roots and stems

secondary growth

growth in girth

produced by nonapical meristems

root cap

protects the root by secreting mucilage and sloughing cells as the root grows through the soil

root apical meristem

behind the root cap and produces all of the new cells for primary growth

zone of elongation

new cells from primary growth elongate (produces primary growth)

root hairs

outgrowths of epidermal cells and are short lived.

increase the surface area of the root

in zone of maturation

epidermis

(root)

outer layer of cells

cortex

(root)

just inside the epidermis

cells contain numerous amyloplasts

Amyloplasts

(root)

starch containing plastids

Endodermis

(root)

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

(root)

inside the endodermis

can become meristematic and produce secondary roots

vascular cylinder

fluid conducting composed of xylem and phloem

xylem

transports water and minerals

phloem

transports water and most organic compounds in the plant (carbs)

tracheids

dead at maturity

water conducting cells in the xylem of angiosperms

long spindle shaped cells with thin areas or apertures called pits

vessel elements

water conducting cells in the xylem of angiosperms

dead and hollow at maturity

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

water moves through in straight open tubes

pits

(tracheids)

thin areas where the cell walls of adjacent cells overlap

water moves through from one cell to the next

sieve cells and sieve tube members

conducting cells in phloem

alive at maturity

cells are small thin walled and arranged in bundles that alternate with the poles of xylem

lignin

molecule that strengthens xylary cell walls

shoot apical meristem

dome shaped

not covered by a capas is the tip of a root

produces young leaves that attach to the stem at a node

leaf primordia

young leaves

axillary bud

young leaf and stem forms a branch or flower

node

where young leaves attach at the stem

terminal bud

contains apical meristem

stem tip

surrounded by bud scales

internodes

space between the nodes

vascular bundle scars

could be visible within the leaf scars

bud scale scars

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

epidermis

(stem)

covers stem

coated with cutin

cutin

waxy waterproof substance on epidermis

cortex

(stem)

below epidermis

stores food

pith

(stem)

center of stem

stores food

collenchyma cells

(stem)

support elongating regions of the plant

smaller rectangular cells with unevenly thickened cell walls

sclerenchyma fibers

thick wall cells outside the phloem

function in support

eudicots

flowering plants with two cotyledons

cotyledons

seed leaves

monocot

flowering plant with only one cotyledon

vascular cambium

eudicot stems

secondary meristem that produces secondary growth

cylindrical and produces secondary xylem to its inside and secondary phloem to its outside

periderm

functions to minimize water loss

consists of cork cells

cork cambium

secondary meristem the produces cork cells

lenticels

gas exchange through the peridermal tissue occurs through structures called

leaves

consist of a blade and petiole

petiole

(leaf)

attaches leaf blade to the stem

simple leaves

one blade connected to the petiole

compound leaves

have several leaflets attached to one petiole

palmate leaflets

arise from a central area (fingers from palm)

pinnate leaflets

arise in rows along a central midline

venation

(leaf)

arrangement of veins

parallel veins

extend the length of the leaf with little or no cross linking

pinnately veined

one major vein from which other veins branch

palmately veined

several veins each having brnaches

phyllotaxis

arrangment of leaves on a stem

opposite phyllotaxis

two leaves per node located on opposite sides of stem

alternate phyllotaxis

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

stomata

pore on the epidermis

surrounded by two guard cells

palisade mesophyll cells

below upper epidermis

contain 50 chloroplasts per cells

Spongy mesophyll

below palisade layer

numerous intercellular spaces

vegetative structures

roots

stems

leaves

we eat and use these

reproductive structures

flowers

fruits

seeds

we eat and use these

dicots

two cotyledons (before genetic analyses)

peduncle

flower stalk

receptacle

flower stalk that bears the floral organs

located at the base of flower usually no large or noticeable

sepals

lowermost or outermost whorls of structures which are usually leaflike

protects the developing flower

androecium

all stamens

-filament

-anther (on top)

pollen grains (inside anther) microgametophytes

gynoecium

all carpels

-ovary (contains ovules) megagametophyte (embryo sac)

-style

-stigma

rises about and inside the androecium

corolla

all petals

calyx

all sepals

petals

located inside and usually about sepals

may be large and pigmented

or inconspicuous

sporophyte

diploid

produces haploid spores by meiosis

gametophyte

haploid spore develops into this by mitosis and cellular differentiation

sporogenesis

production of spores is part of a larger process called