, PLANT BIOLOGY 91mi
WI i
CHAPTER 35 DUNT STRUCTURE ,
GROWTH AND DEVELOPMENT
Wz CHAPTER 36 TRANSPORT
:
VASCULAR PLANTS IN
W3 CHAPTER 37 PLANT NUTRITION
"
W 4,5 CHAPTER 38 REPRODUCTION OF FLOWERING
:
PLANTS
WG 7- CHAPTER 38 PLANTS
BEHAVIOURS
"
, SIGNALS AND
METABOLITES
:
NT
-
PRIMARY METABOLITES : SUGAR , LIPIDS , PROTEINS AND AMINO ACIDS . ARE ESSENTIAL FOR ANY ORGANISM TO
SURVIVE .
'
SECONDARY DERIVED ARE
BIOLOGICAL
METABOLITES
:
FROM PRIMARY METABOLITES ,
OFTEN
ITE ACTIVE PLANTS ,
FOR CELL GROWTH , REPRODUCTION AND DEVELOPMENT .
Y CAN BE
USEFUL BUT CAN BE TOXIC .
USED TO BE CONSIDERED WASTE PRODUCTS .
THEY ARE NOT DIRECTLY
INVOLVED IN THE SURVIVAL OF PLANTS
SECONDARY
'
METABOLITES TYPES :
↳
ALKALOIDS :
COMPOSED MAINLY OF NITROGEN ; WIDELY USED IN MEDICINE
; MOST HAVE A BITTER
TASTE OR ARE POISONOUS WHEN INGESTED PROTECT THE
.
PLANT AGAINST INSECTS , HERBIVORES AND OTHER
PLANTS .
USE BY HUMANS IN FOOD AND MEDICINE ( egg .
Cows ,
COFFEE ,
CHOCOLATE ,
MORPHINE ) .
↳
TERPENOIDS :
MADE OF ISOPRENE UNITS AND ARE FOUND IN ALL PLANTS .
LARGEST GROUP
OF SECONDARY METABOLITES VERY
,
VOLATILE (EVAPORATES EASILY ) .
ESSENTIAL OILS . THEY PRO -
TEC THE PLANT AGAINST HEAT AND DAMAGE ,
ATTRACT POLIN ATOMS ,
ARE WASTE PRODUCTS .
USED BY HUMANS IN MEDICINE , AROMATHERAPY PERFUME AND RUBBER (
leg
.
TAXOL ,
PERFUMES , LATEX ,
etc ) .
b-
PHENOLS :
CONSIST OF A HYDROXYL GROUP ( OH ) ATTACHED TO AN AROMATIC
RING .
FOUND IN NEARLY ALL PARTS OF THE PLANT AND IN NEARLY EVERY PUNT .
P H
DEPENDENT THE ,
SOIL 'S pH CAN BE DETERMINED BY FRUIT COLOUR . ANTI -
OXIDANTS PROTECTION POLLINATORS AGAINST ENVIRONMENTAL
'
-
, , ATTRACTION ,
STRESS
leg . RED DYE , ASPIRING ) .
↳ FLAVONOIDS :
ANTHOCYANINS FLSVONES , AND FLAVDNOLS .
, CHAPTER 35 -
'
DUNT STRUCTURE ,
GROWTH AND DEVELOPMENT W 't
PUNT ORGANS
GH
:
i
'
SHOOT SYSTEM PHOTOSYNTHESIS ( PRODUCTION
:
OF SUGARS ) ,
REPRODUCTIVE ORGANS, TRANSPORT .
-
ROOT SYSTEM :
ANCHORING ,
ABSORPTION OF MINERALS AND
WATER ,
CARBOHYDRATE STORAGE
ROOT SYSTEM :
game
A ROOT IS AN ORGAN WHICH ANCHORS THE PLANTS ,
ABSORBS WATER AND MINERALS
,
AND
STORES CARBOHYDRATES . THE PRIMARY Boot is THE FIRST Theft TO EMERGE ,
FROM SEEDS BECOMES
,
THE TAPROOT ,
WHICH BRANCHES INTO LATERAL Boots ,
IMPROVING ANCHORAGE ,
STABILIZATION AND
WATER ABSORPTION CREATING AN ENVIRONMENT FOR MICROORGANISM
,
.
↳
THETAPROOT PREVENTS THE PUNT FROM TOPPLING
↳
ADVENTITIOUS Boots ARISE FROM STEMS OR LEAVES ,
ANY PART OF THE PLANT .
IN MOST PUNTS 1 ABSORPTION OF WATER AND MINERALS OCCURS NEAR THE TIPS OF THE Roots . ROOT
THE MANY PLANTS HAVE POOT
ADAPTATIONS
HAIRS NEAR THE theft TOP INCREASE THE SURFACE BRED OF ROOT .
WITH SPECIALIZED FUNCTIONS .
SHOOT SYSTEM :
\
A STEM IS AN ORGAN CONSISTING OF THE GROWING SHOOT
TIP ,
DR APICAL BUD WHICH CAUSES,
ELONGATION OF AN YOUNG SHOOT. AN
ALTERNATING SYSTEM OF NODES ,
THE POINTS AT WHICH THE LEAVES ARE
ATTACHED TO .
THE INTERNODES SME THE STEM . SEGMENTS BETWEEN
NODES .
AN AUXILIARY BUD IS A STRUCTURE THAT HAS THE POTENTIAL TO FORM A
LDTEMDL BRANCH , THORN ,
OR FLOWER .
↳
MANY PLANTS HAVE MODIFIED STEMS ( RHIZOMES , STOLONS TUBERS )
boy ,
.
, THE LEAF IS THE MAIN PHOTOSYNTHETIC ORGAN OF MOST VASCULAR PUNTS . LEAVES GENERALLY
CONSISTS OF A FLATTENED BUDE AND A PETIOLE ( STALK ) ,
WHICH Joins THE LEAF TO A NODE OF THE STEM .
↳
FUNCTIONS INTERCEPT
:
LIGHT ,
EXCHANGE GASES TRANSPIRATION ( HEAT
,
DISSIPATION )
,
DEFENSE FROM
HERBIVORES AND PATHOGENS ( Thick @ MES ) .
*
IN CLASSIFYING ANGIOSPERMS ,
TAXONOMISTS MAY USE LEAF MORPHOLOGY AS A CRITERION
↳
SOME SPECIES HAVE EVOLVED MODIFIED LEAVES THAT SERVE VARIOUS FUNCTIONS
( SPINES IN CACTI REPRODUCTIVE LEAVES SUCCULENTS STORAGE LEAVES ONIONS , TENDRILS
ng
- - -
.
, ,
VINES) IN SOME
*
PANTS TENDRILS ARE MODIFIED STEMS , YEARLY PLANTS HAVE LEAF TENDRILS ,
MORE PERMANENT
PLANTS HAVE STEM TENDRILS .
PLANT TISSUES
"
FLACH DUNT ORGAN HAS DERMAL , VASCULAR , AND GROUND TISSUES , EACH OF WHICH FORMS A TISSUE SYSTEM .
EACH
TISSUE SYSTEM IS CONTINUOUS THROUGHOUT THE PLANT .
'
ITE DERMAL TISSUE SYSTEM CONSISTS OF THE EPIDERMIS
'
ITE VASCULAR TISSUE SYSTEM FACILITATES THE TRANSPORT OF WATER , CARBOHYDRATES ,
MATERIALS ,
etc
,
THROUGH THE PUNT AND PROVIDES MECHANICAL SUPPORT .
'
TIE GROUND TISSUE SYSTEM ARE TISSUES THAT ARE NEITHER DERMAL NOR VASCULAR .
STORAGE
AND PHOTOSYNTHESIS .
DERMAL TISSUE SYSTEM :
IN NON WOODY PLANTS , THE DERMAL TISSUE SYSTEM CONSISTS OF THE EPIDERMIS ,
A WAXY COATING CALLED THE CUTICLE HELPS PREVENT WATER LOSS FROM THE EPIDERMIS .
IN WOODY PLANTS , PROTECTIVE TISSUES CSLLED PERIDERM REPLACE THE EPIDERMIS IN
OLDEN REGIONS OF STEM AND MOOTS .