Plant Reproduction

4.7  Plant Reproduction

 Structure and Functiion of parts of Flowers

 Pollination

 

Types of flower
Unisexual

Example:

Corn flower, papaya flower

Bisexual

Example: 

Rose and Sunflower

 

Types of pollination
Self-pollination Cross-pollination
  • Pollen grains are transferred to the stigma of another flower on the same plant
  • Pollen grains are transferred to the stigma of the same flower
  • Pollen grains are transferred to the stigma of another flower on a differentt plant of the same species.

 Pollinating Agents

Animals and insects

  • Polllen grains usually stick on the beak or body of the animal.
    When an insect lands on a flower to suck its nectar, pollen grains will stick to its furry feet and body.
  • The characteristics of animal-pollinated and insect-pollinated flowers: 
  • - have big and colourful petals
  • - have nectar and smell nice
  • - produce rough and sticky pollen grains
  • Examples of animal-pollinated flowers and insect-pollinated flowers are durian, rambutan, papaya, hibiscus, sunflower and rose.

Wind

  • Light pollen grains are blown by the wind and reaches the stigma of another flower.
  • The characteristics of wind-pollinated flowers:
  • - have white or pale petals
  • - have a long and furry stigma
  • - have plenty of small, smooth and light pollen grains
  • - have a long filament and style
  • Examples of wind-pollinated flowers are corn, grass and paddy.

 

The Advantages of Cros-Pollination

  • New plants that are more resistant to pests and diseases
  • Healthier plants which can adapt better to changes in the environment
  • New varieties of plants
  • Good quality seeds

The Innovation of Cross-Pollination in Agriculture

Plant and parent plants Hybrid plant

Characteristics of hybrid plant

Palm oil

Pisifera and Dura

Tenera

More fruits

Flesh

Thinner shell

Papaya

Subang 6 and Sunrise Solo

Eksotika

Sweeter

Bigger fruits

Fertilisation Process

 Structures of a Seed and Their Functions

Structure of dicotyledon Structure of monocotyledon

 

The structure and functions of a seed
Part Structure Function
External Testa Protects the seed
Hilum Place where the seed sticks to the frui
Micropyle Small hole to allow air and water to enter the seed
Embryo Plumble Part of the embryo which develops into a new
shoot
Radicle Part of the embryo which develops into the root
Cotyledon / Endosperm Stores and provides food for the seed

 Germination of Seeds

Epigeal germination
Hypogeal germination

 

The Conditions Required for Germination of Seeds

  • Water
  • Air
  • Suitable temperature

Plant Reproduction

4.7  Plant Reproduction

 Structure and Functiion of parts of Flowers

 Pollination

 

Types of flower
Unisexual

Example:

Corn flower, papaya flower

Bisexual

Example: 

Rose and Sunflower

 

Types of pollination
Self-pollination Cross-pollination
  • Pollen grains are transferred to the stigma of another flower on the same plant
  • Pollen grains are transferred to the stigma of the same flower
  • Pollen grains are transferred to the stigma of another flower on a differentt plant of the same species.

 Pollinating Agents

Animals and insects

  • Polllen grains usually stick on the beak or body of the animal.
    When an insect lands on a flower to suck its nectar, pollen grains will stick to its furry feet and body.
  • The characteristics of animal-pollinated and insect-pollinated flowers: 
  • - have big and colourful petals
  • - have nectar and smell nice
  • - produce rough and sticky pollen grains
  • Examples of animal-pollinated flowers and insect-pollinated flowers are durian, rambutan, papaya, hibiscus, sunflower and rose.

Wind

  • Light pollen grains are blown by the wind and reaches the stigma of another flower.
  • The characteristics of wind-pollinated flowers:
  • - have white or pale petals
  • - have a long and furry stigma
  • - have plenty of small, smooth and light pollen grains
  • - have a long filament and style
  • Examples of wind-pollinated flowers are corn, grass and paddy.

 

The Advantages of Cros-Pollination

  • New plants that are more resistant to pests and diseases
  • Healthier plants which can adapt better to changes in the environment
  • New varieties of plants
  • Good quality seeds

The Innovation of Cross-Pollination in Agriculture

Plant and parent plants Hybrid plant

Characteristics of hybrid plant

Palm oil

Pisifera and Dura

Tenera

More fruits

Flesh

Thinner shell

Papaya

Subang 6 and Sunrise Solo

Eksotika

Sweeter

Bigger fruits

Fertilisation Process

 Structures of a Seed and Their Functions

Structure of dicotyledon Structure of monocotyledon

 

The structure and functions of a seed
Part Structure Function
External Testa Protects the seed
Hilum Place where the seed sticks to the frui
Micropyle Small hole to allow air and water to enter the seed
Embryo Plumble Part of the embryo which develops into a new
shoot
Radicle Part of the embryo which develops into the root
Cotyledon / Endosperm Stores and provides food for the seed

 Germination of Seeds

Epigeal germination
Hypogeal germination

 

The Conditions Required for Germination of Seeds

  • Water
  • Air
  • Suitable temperature