Seed Plants Seed Plants
Gymnosperms & AngiospermsGymnosperms & Angiosperms
What is a seed??What is a seed??
A seed contains an embryonic sporophyteA seed contains an embryonic sporophyte It has a protective coat and enough nutrients to It has a protective coat and enough nutrients to
support the sporophyte until it is ready to support the sporophyte until it is ready to germinategerminate
Seeds differ depending on their mode of Seeds differ depending on their mode of species dispersal …eg: wind, animals, water species dispersal …eg: wind, animals, water etc.etc.
Gymnosperm = “Naked Seeds”Gymnosperm = “Naked Seeds”
In gymnosperms the In gymnosperms the seeds are uncovered or seeds are uncovered or “naked”“naked”
They are often exposed They are often exposed on the surface of scales on the surface of scales in conesin cones
Angiosperm SeedsAngiosperm Seeds
In angiosperms, the In angiosperms, the seeds are covered by seeds are covered by fruitfruit
Seed Plant Life CycleSeed Plant Life Cycle
A seed germinates into a sporophyteA seed germinates into a sporophyte The sporophyte produces megaspores and The sporophyte produces megaspores and
microspores by meiosismicrospores by meiosis The spores develop into megagametophytes The spores develop into megagametophytes
and microgametophytesand microgametophytes Fertilization takes placeFertilization takes place A seed is formedA seed is formed
Two Types of GametesTwo Types of Gametes
MicrosporesMicrospores develops into a develops into a
microgametophyte microgametophyte In seed plants this is the In seed plants this is the
POLLEN grainPOLLEN grain
MegasporesMegaspores Develops into a Develops into a
megagametophytemegagametophyte In seed plants this is the In seed plants this is the
EMBRYO sacEMBRYO sac
General Life Cycle…General Life Cycle…
In Gymnosperms….In Gymnosperms….
In Angiosperms…In Angiosperms…
GymnospermsGymnosperms
Includes Cycads, Gingko and ConifersIncludes Cycads, Gingko and Conifers
Gymnosperm Adaptations to Gymnosperm Adaptations to Land…Land…
SeedsSeeds allow for species dispersal on land allow for species dispersal on land NeedlesNeedles maintain water balance in dry cold maintain water balance in dry cold
climatesclimates Vascular tissueVascular tissue transports nutrients and transports nutrients and
water from surroundings throughout the plantwater from surroundings throughout the plant Pollen Pollen can be transported by wind, animals can be transported by wind, animals
or insects for fertilization or insects for fertilization
AngiospermsAngiosperms
An exceptionally large and successful group of An exceptionally large and successful group of plantsplants
Includes:Includes: All deciduous treesAll deciduous trees All broad leafed evergreen treesAll broad leafed evergreen trees All non-woody plants such as grasses, garden All non-woody plants such as grasses, garden
plants, flowering plantsplants, flowering plants
Some examples of angiosperms…Some examples of angiosperms…
Two Groups of Angiosperms..Two Groups of Angiosperms..Monocotyldons & DicotyldonsMonocotyldons & Dicotyldons
Flower StructureFlower Structure Heterospores (microspores & megaspores) are produced Heterospores (microspores & megaspores) are produced
within flowerswithin flowers SepalSepal
green, beneath the petals, protect the developing flowergreen, beneath the petals, protect the developing flower PetalsPetals
attract pollinatorsattract pollinators PistilPistil
vaselike structure in the centre of the flower, has 3 parts; stigma, style vaselike structure in the centre of the flower, has 3 parts; stigma, style & ovary& ovary
Stigma is an enlarged, sticky knob at the top of the pistil (sticks to pollen)Stigma is an enlarged, sticky knob at the top of the pistil (sticks to pollen) Style is the stalk between the stigma and the ovaryStyle is the stalk between the stigma and the ovary Ovary is the enlarged base containing ovulesOvary is the enlarged base containing ovules
StamensStamens grouped around the pistil, has 2 parts; the filament and the anthergrouped around the pistil, has 2 parts; the filament and the anther
Anther has 2 pollen sacsAnther has 2 pollen sacs Filament attaches the pollen sac to the flowerFilament attaches the pollen sac to the flower
Plant ReproductionPlant Reproduction
Pollen is produced by the stamenPollen is produced by the stamen Pollen moves away from the plant by wind or Pollen moves away from the plant by wind or
pollinatorspollinators The pollen lands on the pistil of another flower The pollen lands on the pistil of another flower
and fertilizes the eggs within the ovaryand fertilizes the eggs within the ovary The flower petal falls off and the ovary The flower petal falls off and the ovary
develops into a fruit that encloses the seedsdevelops into a fruit that encloses the seeds Fruits are dispersed in a variety of waysFruits are dispersed in a variety of ways EgEgeaten by animals, acorns, dandelions etc.eaten by animals, acorns, dandelions etc.
Flower StructureFlower Structure
AssignmentAssignment Prepare a summary chart comparing angiosperms and Prepare a summary chart comparing angiosperms and
gymnospermsgymnosperms
GymnospermGymnosperm AngiospermsAngiosperms
General General Characteristics Characteristics
Life Cycle and Life Cycle and Reproductive Reproductive StructuresStructures
Adaptations & Adaptations & Unique Unique CharacteristicsCharacteristics
Examples & Examples & ClassificationClassification