Brooks Exam 3 QUESTIONS AND ANSWERS
Ontogeny recapitulates phylogeny
if early developmental stages of animals are compared there are significant similarities
leaves
plant collection and conversion of solar energy
Stems
plant positioning and support of leaves
Roots
plant anchorage and absorption
Vascular System
plant transport
Make up Epidermis (Leaf)
Cuticle, guard cells w/ Stomata
Make up Mesophyll (middle leaf)
Parenchyma (dicots w/ palisade and spongy)
Leaf Cuticle
layer of wax, non-living
Stomata positioning
mostly on lower surface of leaf
Leaf Vein
Vascular bundle
Make up Stem Structure
Epidermis and Cortex
Cortex Supporting Structure
Collenchyma and Sclerenchyma
,Collenchyma
alive at maturity, stem supporting tissue, like strands in celery
Sclerenchyma
dead at maturity, stem supporting tissue
Fibers
Make up sclerenchyma, were used to make rope
Sclerids
Make up sclerenchyma, like granules in a pear, walnuts
Vascular Tissue
xylem, phloem, vascular bundles, procambium (vascular cambium)
Procambium (vascular cambium)
Produces phloem and xylem
Pith
Central stem structure found in dicots
Ground Parenchyma
Stem structure found in monocots
Companion Cells
What plant tissue is most metabolically active?
Xylem
Tracheids, vessel member
Tracheids
Xylem: vestigial trait (not very efficient), narrow, have perforated cell walls, slow flow,
dead
Vessel Member
Xylem: thick, hollow, dead cells with large holes on end (allow better water flow)
Phloem
sieve tube member, companion cell
Sieve Tube member
Phloem: not very metabolically active, hollow living cells w/ perforated ends
Companion cell
, Phloem: keeps sieve tube member alive, shares resources and nutrients, very
metabolically active
Epidermis w/ Root Hairs
Root structure: helps seedling absorb water quickly and immediately
Endodermis w/ Casparian Strips
Root structure: endodermis filters water while Casparian strips are waves that prevent
water from passing through endodermal cells
Stele
Root structure: central structure with vascular tissues inside
Apoplastic Pathway
water enters through epidermis and pass in the spaces between cortex cells until
reaching the endodermis
Symplastic Pathway
water is forced through cell membranes of endodermis where it is filtered before
reaching the vascular tissues within the stele (removes potentially harmful substances)
Root Nodules and Bacteria
bacteria fix nitrogen and are housed in root nodules to supply "fertilizer", allows plant to
thrive even in nitrogen poor soil
Nitrogenace
enzyme that breaks down nitrogen, doesn't like oxygen
Modified Root Nodules
house bacteria and fungi that break down nitrogen (and protect from oxygen)
Vegetative Reproduction
Plant asexual reproduction
Runner (stolon)
Strawberry: new plants arise at nodes on an above-ground horizontal stem
Rhizome
Bermuda Grass: new plants arise at nodes of underground horizontal stem
Corm
Gladiolus: new plant arises from axillary bud on short, thick vertical underground stem
Tuber
Ontogeny recapitulates phylogeny
if early developmental stages of animals are compared there are significant similarities
leaves
plant collection and conversion of solar energy
Stems
plant positioning and support of leaves
Roots
plant anchorage and absorption
Vascular System
plant transport
Make up Epidermis (Leaf)
Cuticle, guard cells w/ Stomata
Make up Mesophyll (middle leaf)
Parenchyma (dicots w/ palisade and spongy)
Leaf Cuticle
layer of wax, non-living
Stomata positioning
mostly on lower surface of leaf
Leaf Vein
Vascular bundle
Make up Stem Structure
Epidermis and Cortex
Cortex Supporting Structure
Collenchyma and Sclerenchyma
,Collenchyma
alive at maturity, stem supporting tissue, like strands in celery
Sclerenchyma
dead at maturity, stem supporting tissue
Fibers
Make up sclerenchyma, were used to make rope
Sclerids
Make up sclerenchyma, like granules in a pear, walnuts
Vascular Tissue
xylem, phloem, vascular bundles, procambium (vascular cambium)
Procambium (vascular cambium)
Produces phloem and xylem
Pith
Central stem structure found in dicots
Ground Parenchyma
Stem structure found in monocots
Companion Cells
What plant tissue is most metabolically active?
Xylem
Tracheids, vessel member
Tracheids
Xylem: vestigial trait (not very efficient), narrow, have perforated cell walls, slow flow,
dead
Vessel Member
Xylem: thick, hollow, dead cells with large holes on end (allow better water flow)
Phloem
sieve tube member, companion cell
Sieve Tube member
Phloem: not very metabolically active, hollow living cells w/ perforated ends
Companion cell
, Phloem: keeps sieve tube member alive, shares resources and nutrients, very
metabolically active
Epidermis w/ Root Hairs
Root structure: helps seedling absorb water quickly and immediately
Endodermis w/ Casparian Strips
Root structure: endodermis filters water while Casparian strips are waves that prevent
water from passing through endodermal cells
Stele
Root structure: central structure with vascular tissues inside
Apoplastic Pathway
water enters through epidermis and pass in the spaces between cortex cells until
reaching the endodermis
Symplastic Pathway
water is forced through cell membranes of endodermis where it is filtered before
reaching the vascular tissues within the stele (removes potentially harmful substances)
Root Nodules and Bacteria
bacteria fix nitrogen and are housed in root nodules to supply "fertilizer", allows plant to
thrive even in nitrogen poor soil
Nitrogenace
enzyme that breaks down nitrogen, doesn't like oxygen
Modified Root Nodules
house bacteria and fungi that break down nitrogen (and protect from oxygen)
Vegetative Reproduction
Plant asexual reproduction
Runner (stolon)
Strawberry: new plants arise at nodes on an above-ground horizontal stem
Rhizome
Bermuda Grass: new plants arise at nodes of underground horizontal stem
Corm
Gladiolus: new plant arises from axillary bud on short, thick vertical underground stem
Tuber
