ECO LAB EXAM 2

Labs 4-6

type of growth axillary buds responsible for

lateral growth of branches leaves flowers

in angle between leaf and stem at nodes

type growth apical buds responsible for

vertical growth

at tip/apex of shoots and roots

method of pollination used by gymnosperms vs angiosperms

gymnosperms: wind dispersal

angiosperms: animal dispersal

what type symmetry more common

radial symmetry

male reproductive flower parts

anther + filament = stamen

female reproductive flower parts

stigma + style + ovary = pistil

receptacle

base above peduncle where sepals, petals, stamen, pistil attach

why might plant produce dry fruit instead of fleshy fruit

save energy for other processes like making seeds that get dispersed by wind/water instead of animals

why some plants winter deciduous

drop leaves to avoid energy loss when limited sunlight in winter

why some plants summer deciduous

drop leaves survive hot and dry summers avoid dehydration

angiosperms tend have what kind venation

pinnate venation

how many leaves at nodes for alternate, opposite, whorled

alternate - one

opposite - two

whorled - three or more

pulvinus

nastic movement - make leaves/leaflets gain/lose water, move in no particular direction toward stimulus

prickles

sharp projections of epidermis

randomly dispersed

easier to break off than thorns

ex: eggplant calyx

thorns

sharpened shoots on leaf axil

bigger than prickles

only come out at nodes

plants

multicell euks - land, freshwater, marine envirs.

modular growth form - some organs indeterminate in growth

can regen limbs

plant organs

stems

leaves

roots

flowers (angio), cones (gymno)

fruits (fertilized flowers)

plant shoots consist of

stems, leaves, reproductive organs

leaves and reproductive organs attach at

nodes of stem

buds

small, embryonic shoots

active grow or dormant

can diff locations and have immature leaves/flowers/both

2 types: apical (terminal), axillary (lateral)

apical meristem

region of roots and shoots where undifferentiated stem cells actively divide

banana squash

Cucurbita maxima

apical (terminal) buds

tips of shoots + roots (vertical growth)

releases hormone AUXIN inhibit lateral growth

axillary (lateral) buds

at nodes, 1 above each leaf just where leaf petiole attaches to stem

auxin effect on plants

when cut near base of stem to remove auxin source

branches further away from cut grow wider angles

male gymnosperm cones

pollen cones

papery, release pollen

female gymnosperm cones

seed cones

generally woody, contains seeds

Coastal Redwood

Sequoia sempervirens

sepals

green leaf like modified leaf at flower base

colorful petals above sepals

protect as blooms

peduncle function

hold up flower, provide nutrients

ovule

produces eggs

house female gametes

nutrients for embryo develop

protective layers

petals and stamen arrangement

can be alternate or opposite (switch between or line up)

petals can be

free or partly fused into a ring/tube

ovary function

initially - protect ovules

after pollination - protect developing seed embryos

swells to form fruit

aid mature seed dispersal

fruits

mature ovaries

ovary wall with internal seeds

dry or fleshy

dry fruits

outer wall stays closed / split open release seeds

capsules, legumes, nuts

capsules

split open release seeds

ex: okra, Crepe Myrtle

legumes

pod like fruits, open or close

ex: green beans, edamame

nuts

thick wall doesn’t open

only 1 single seed inside

ex: acorns, hazelnut

fleshy fruit

thick juicy wall doesn’t crack open

berries, drupes, pomes

berries

entirely fleshy fruit wall

ex: avocado, banana

drupes

large pit center with single seed

ex: peach, plum, almond

pomes

like berries but outer skin and flesh derived from receptacle

not ovary wall

ex: apple, pear

evergreen leaf retention

keeps leaves all year but periodically shed old leaves

Maidenhair tree

Ginkgo biloba

stalk/petiole

attaches leaf to stem

sessile leaves

no petioles

leaf connects directly to stem

leaf veins

vascular tissues run throughout leaf

parallel, pinnate, palmate

leaf arrangement - simple

no leaflets, undivided leaf blade

lobed = simple

leaf arrangement - compound

leaflets, arise from division of leaf blade

pinnate, twice pinnate, palmate

leaf arrangement - pinnately compound

rachis - midrib where leaflets arise

leaf arrangement - twice pinnately compound

1° leaflets divide into 2° leaflets

midrib of 1° leaflet now 2° rachis

leaf arrangement - palmately compound

no visible rachis

leaflets clustered at tip of petiole

leaf ranking view

look down from top of stem at tip shoot

see how leaves arranged around stem

leaf ranking - alternate spiral

most common

spiral staircase

leaf ranking - distichous

2-ranked

flat like fan

can be alternate/opposite

leaf ranking - decussate

in opposite leaves

perpendicular node to node

leaf shapes

linear, oval, oblong, ovate (most common)

obovate, deltoid, cordate, elliptical, lanceolate

leaf margins

(4) entire, dentate, lobed, serrate

others: ciliate, crenate, sinuate, lacerate, undulate, pectinate, pinnatifid

leaf apices (apex)

acute (most common)

acuminate, aristate, cuspidate, mucronate

obtuse, retuse, emarginate

leaf bases (can be asymmetrical)

cuneate, attenuate, obtuse, cordate

auriculate, sagittate, truncate

bract

modified leaf associated w flower/cluster flowers

tend smaller than leaves

sometimes diff color/texture

stipules

appendages sometimes present either side of base petiole

can be fused to petiole, spine like, leaf like, form tendrils help climb

or just appear as narrow hairs, dots, glands

when check: look at youngest leaves near shoot tip

spines

modified lea