B Barber
Science Coordinator

Partner Primary & Secondary Schools
John Paul, Nazareth, Padua, St John's Reg. Colleges & Partner Primary

Science
Middle Years Science Program - Plant Show

Middle Years Science Program

 
"Plant Show" (Junior)
Return to Science Shows
Program: Clare Freston, Lyn Bonner & Joelle Dardene (St Anne's) 9.00-10.30am (2 shows).

Presentation:

Equipment:

  1. Microscopes (x5) with set of plant slides
  2. Microviewers (x5) with set of plant slides
  3. Stereo microscope (x2)
  4. Posters: stem, flower, roots, leaves
  5. Hand magnifying glasses (x5)
  6. A4 paper worksheet for illustrating slides

Handout: Plant sheet

Notes:

Topics:

  • basic structure of plants: flowers, stomata, leaves, stem
  • flowering versus non-flowering plants
  • climate and survival
  • how do plants reproduce?
  • types of plants

Basic structure of a plant: Plants are made up of a number of parts: the roots which carry water and minerals up into the plant and provide the plant with structural support; the stem which contains the phloem (channels that transport nutrients to other parts of the plant) and xylem (very strong cellulose lined channels that transport water way up into the leaves of the plant); the green leaves that provide through photosynthesis the transforming of sunlight into stored chemical energy; and the flowers or buds responsible for plant reproduction.

Flowering versus non-flowering plants: All flowering plants are termed angiosperm (as opposed to gymnosperm which are nut, pod or budding plants). Inside each seed there is 1 or 2 cotyledons. Plants with 1 cotyledon are called Monocotyledon and plants with 2 are called Dicotyledons. The classification of these two is below ...

Characteristic
Monocotyledon
Dicotyledon
Leaves usually long and thin with parallel rows of veins generally broad leaf with branching veins
Flowers often in 3's or multiples of 3 usually in multiples of 4 or 5
Root system fibrous roots usually tap roots
Stem usually soft may be soft or woody
Examples grasses, oats, kangaroo grass, bamboo, maize, orchids, flax lillies, asparagus daisies, dandelion, gum trees, bottlebrushes, tea-trees; orange or lemon trees; wattles, banksias, grevilleas

Leaves: Plants get their energy from the sun in a process called photosynthesis. This occurs in green leaves when carbon dioxide and water with the help of the green pigment chlorophyll are changed into glucose and oxygen. In the dark, plants cannot photosynthesize. They must have the sun in order to survive. Looking at a plant up close you will find small holes on the under side of the leaves called stomata through which The energy they make is either used straight away by the plant; stored as starch or oil in the stem, roots or fruits; used to make cellulose for the cell walls; or combine with minerals to make proteins for plant growth.

Composition and Types of Soil: What is soil? It is a complex mixture of minerals and organic matter. The minerals come from the disintegrated rock, the organic matter from decomposed plant and animal matter. Mixed in with this is water, air and numerous living organisms. The main function of soil is to provide plants with nutrients, water, oxygen and anchorage for the root system. Soil is constantly changing. Natural changes include the weather, insects, worms, bacteria and fungi. Adding fertilizer, chemicals and mulch can completely alter soil type. Most soil falls into two categories: heavy or light depending on the amount of clay or silt (fine particles) or sand (coarse particles) they have. Clay is made from very fine particles that pack together closely, thus hindering the downflow of water and air which are both essential for plant growth. Gypsum can break this up and allow the plant to take in water and air.

In clay soils in a large downpour, plant root may end up very wet and stay wet resulting in the rotting of tree roots - the spaces between clay particles are filled with water. Sandy soils are light because they are much easier to dig when wet or dry. Sandy soil drains faster but they may dry out too fast.Sany soils must be have rainfall more frequency. They must also be fertilized more often since their nutrients wash away quickly. Loamy soil is half way between the two and is ideal for plants. To identify soil types, follow the steps below ...

  • Clay soil: This type of soil and be worked like plasticine. When wet it becomes a solid mass.
  • Sandy soil: This type of soil cannot be formed into shapes or ribbons in your hand ... they simply fall apart.
  • Loamy soil: This can be shaped but will fall apart easily.

Climate and survival: Plants require many nutrients, minerals, carbon dioxide and sunlight to survive. Without all of these they would certainly die ...

How do plants reproduce? Within the flowers there are petals and nectaries used to lure insects and other animals in order to assist in delivering the pollen. Pollen is produced in pollen sacs and pollinate another plant or the same plant when they land on the carpel within a flower. After pollen lands on the stigma of a flower, pollen then travels through the style into the ovary. It is here that the pollen may fertilise the awaiting egg. Pollination occurs when the pollen grain reaches the stigma. Plants may self-pollinate their own stigma or travel from one plant to another and pollinate another plant by cross-pollination. They may travel their by insects, animals or the wind.

Another way for a fruiting plant to reproduce is the find ways to disperse their seeds. Plants can disperse their seeds using animals or birds (eg. tomatoes, grapes and apple trees), water (eg. coconuts) or wind (grasses and dandelion). Within the seed is largely cotyledons which contains rich nutrients for the seed to grow; the plumule which is the infant plant shoot and the radicle which is the infant plant roots. When a seed has dropped there is 3 conditions required before it can germinate. Water is necessary for the seed to swell and burst open and then transport food to the growing embryo; oxygen is needed to help provide the plant with the necessary energy to grow; and temperature conditions depending on the type of plant. Light is not necessary for germination but will be required soon to help the newly developing plant to start to use the sun to obtain energy for further growth.

Types of plants: We can classify plants in to different groups. The plant kingdom is made up of the following ...
Plant Kingdom
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Contains vascular material
(eg. phloem or xylem)

Does not contain vascular material
(found in damp )
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Tracheophyte

Bryophyte
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with seeds
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with no seeds
small delicate leaves
thick leathery leaves
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no flower, seeds in cones
flowers with seed
no seeds
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Gymnosperm
(Conifers)
Angiosperm
(Flowering plants)
Pteridosperms
(Ferns)
Mosses
Liverworts

Plant Kingdom detail:

Bryophytes
Pteridophytes
Angiosperms
Gymnosperms
Mosses and liverworts
Ferns
Flowering plants
Conifers
  • Found mainly in damp places
  • Root-like structures very fine and hair-like
  • Simple leaves or leaf-like structures
  • Usually only several centimetres long
  • Spores are formed in a capsule
  • Found in poist, shaded areas
  • No flowers, cones or seeds
  • Found on the underside of leaf-like fronds
  • Have proper roots and stems
  • Most less than a metre high (except tree ferns)
  • Most found on land
  • Most common type of plant
  • Produce flowers, fruits and seeds
  • Have true roots, stems and leaves
  • Found on land
  • Have true roots, stems and leaves
  • No flowers
  • Form seeds between scales of a woody cone
  • Most have fine, needle-like leaves
Examples
Examples
Examples
Examples
Mosses, liverworts maidenhair fern, tree fern, bracken Fruit trees, cereal crops, wattles, vegetables Cypress, pine, cedar