Starter

What do the following words mean to you? Write them in your jotters

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1. Sexual reproduction
2. Gamete
3. Pollination
4. Asexual reproduction
5. Clone

Propagating and Growing Plants

Starter

What do the following words mean to you? Please write them in your jotters

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1. Sexual reproduction - Two parents producing non-identical offspring
2. Gamete – Sex cell
3. Pollination - The act of transferring pollen grains from the male anther of a flower to the female stigma
4. Asexual reproduction - One parent producing identical offspring
5. Clone - organism that is genetically identical to its parent

Propagating and Growing Plants

Unit 2 Key Area 2: Propagating and Growing Plants

This Photo by Unknown Author is licensed under CC BY-NC-SA

Learning Intentions

Success Criteria

I can explain the meaning of propagation.

I can state the conditions needed for seeds to germinate.

I have planned an investigation into conditions necessary for the germination of seeds.

I can describe different ways plants reproduce asexually

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Learning intentions

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To learn about propagation of plants both sexually and asexually.

Propagating Plants?

Propagating Plant from Seeds

The number of plant can be increased by sowing seeds which are the product of sexual reproduction in flowering plants.

Seeds contain the genetic information that came from two parent plants. This means that seeds are genetically different from each other.

Growing Plants from seeds

Germination is the development of a plant embryo into an independent plant with green leaves.

During germination the food store present in the seed leaves is digested to give the young plant food and energy for growth.

Seed Dissection

1. Peel of the tough outer casing.
2. Split the seed in half.
3. Can you identify the embryo?
4. Press into the seed with your finger nail, then drop iodine on it. What do you see?

Tough outer layer

Food store

Embryo

Conditions for Germination

Giving the right conditions, seeds will germinate and grow into new plants. Usually when the volume of water, oxygen availability and temperature are all correct.

• Water helps the seed to swell and splits to work more water into the seed.
• Oxygen is needed for respiration which releases the food store’s energy.
• Temperature affects the chemical reactions that take place during germination.
• Some seeds need to be on the soil surface in the light to germinate while others, beneath the soil surface, will only germinate in the dark.

Conditions for Germination

W. O. W.

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Water

Oxygen

Warmth (temperature)

Learning Intentions

Success Criteria

I can explain the meaning of propagation.

I can state the conditions needed for seeds to germinate.

I have planned an investigation into conditions necessary for the germination of seeds.

I can describe different ways plants reproduce asexually

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Learning intentions

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To learn about propagation of plants both sexually and asexually.

What are the variables?

• Independent
• Dependent
• Control

Investigating Germination

Method:

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1. Take four small balls of cotton wool and press each down to the bottom of four petri dishes
2. Add 10 cress seed on top of the cotton wool in each petri dish.
3. Into each of the tubes, add enough water to soak the cotton wool but don’t drown the seeds.
4. Label each petri dish with a marker
5. Place the petri dishes in different environments.
6. Check back next week to see how many of your seeds have started to grow.

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Aim: to investigate the effect of temperature on seed germination

Equipment

• 16 x cotton wool
• 4 x petri dishes
• 40 seeds
• Water

Investigating Germination

Result:

Draw a line graph of your result.

National 4 Biology

Unit 2 LO1:

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Design an experiment to show the importance of one factor in seed germination.

Investigation planning sheet

Conclusion:

• Describe the effect of increasing temperature on the germination of cress seeds. Your description must relate to the aim.
• Can you use your knowledge of enzymes to explain the pattern you have found?

Evaluation:

• Can you identify any sources of error?
• If you could do the experiment again, how could you improve the method?

Investigating Germination

LO

Aim: To investigate the importance of _______ in seed germination

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Equipment:

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Method:

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Results:

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Conclusion:

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Evaluation:

Example

LO

Aim: To investigate the importance of _______ in seed germination

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Equipment: Equipment list is present and includes ALL items used

Method:

1. Clearly describes how the dependent variable is measured
2. Method is clearly written and easy to follow AND has included any health and safety concerns
3. Procedures have been followed safely

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Results:

• Data is recorded in a suitable table which contains correct headings and SI units.�Data has been correctly processed.
• Appropriate graph to present data is chosen
• Graph is plotted correctly, axes have been labelled correctly and contain correct SI units. Scale is linear

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Conclusion: Conclusions refer to the aim of the investigation and are supported by the results.

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Evaluation: Evaluation provides at least one possible improvement that is relevant for the experiment

What are the variables?

• Independent
• Dependent
• Control

Investigating Germination

Method:

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1. Take four small balls of cotton wool and press each down to the bottom of four petri dishes
2. Add 10 cress seed on top of the cotton wool in each petri dish.
3. Into each of the tubes, add enough water
4. Label each petri dish with a marker
5. Place the petri dishes in the different environments.
6. Check back next week to record how many seeds have started to grow.

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Aim: to investigate the effect of temperature on seed germination

Equipment

• 16 x cotton wool
• 4 x petri dishes
• 40 seeds
• Water

Investigating Germination

Result:

Draw a bar graph of your result.

1. Finish your Practical write up in your assessment jotter
2. Check your seeds and fill in your results table
3. Draw a bar graph
4. Write a conclusion
5. Write an evaluation

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If you finish:

TASK 1: Read Pages 161 to 163 and take notes under the following headings:

-Vegetative propagation

-Bulbs

-Tubers

-Runners

-Artificial propagation (cuttings.)

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TASK 2: Answer Question 1 on page 162

TASK 3: Complete the chapter assessment on page 164

Extension: Chapter assessment page 158

Learning Intentions

Success Criteria

I can explain the meaning of propagation.

I can state the conditions needed for seeds to germinate.

I have planned an investigation into conditions necessary for the germination of seeds.

I can describe different ways plants reproduce asexually

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Learning intentions

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To learn about propagation of plants both sexually and asexually.

• Asexual reproduction involves just one parent plant.
• There are no sex cells involved.
• The new plants are genetically identical clones of the parent.

Asexual Reproduction in Plants

Vegetative propagation

Is a type of asexual reproduction used by plants.

It can occur naturally or be artificial propagation carried out by humans.

Research Task

Read Pages 161 to 163 and take notes under the following headings:

-Vegetative propagation

-Bulbs

-Tubers

-Runners

-Artificial propagation (cuttings.)

Propagating Plants

In your jotter – use your notes to help you

Starter: Draw the table and compare sexual and asexual reproduction

Your Task

In your jotter

Compare sexual and asexual reproduction

Multicellular organisms

Key area 1 Key Revision Notes

Asexual Reproduction ensures that:

1) Only one adult is needed for reproduction

2) Reproduction is fast

3) The offspring are identical to the parent.

Sexual Reproduction ensures that:

1) Two adults are required for reproduction.

2) There is greater variation within the species.

Bulbs

Some plants such as potatoes and dahlia reproduce using tubers.

Food made in the leaves is stored in the tubers and used as an energy source for new growth.

Tubers

Runners

Artificial Propagation

A large number of identical plants can be produced quickly by taking advantage of the ability of plants to regenerate.

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A small piece of leaf, stem or shoot can be used to grow a new genetically identical plant.

Cuttings

Small pieces of stem are cut from a healthy plant and placed in water, soil or a rooting medium to encourage root growth.

A portion of a plant with good flower or fruit growth is taken and joined to a plant with a, strong root system.

Roses

Grafting

The stem of the parent plant is bent until it touches the ground. It is then held in place until roots have formed.

Layering

Learning Intentions

Success Criteria

I can explain the meaning of propagation.

I can state the conditions needed for seeds to germinate.

I have planned an investigation into conditions necessary for the germination of seeds.

I can describe different ways plants reproduce asexually

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Learning intentions

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To learn about propagation of plants both sexually and asexually.

Title of Poster: Asexual Plant Reproduction �Create a poster on the different methods of plant reproduction. Include pictures and labelled diagrams for each method.

Some plants such as potatoes and dahlia reproduce using tubers.

Food made in the leaves is stored in the tubers and used as an energy source for new growth.

Some plants such as daffodils and onions reproduce using bulbs.

A bulb has thick fleshy leaves full of stored food which is used for the growth of a new plant the following year

Some plants such as strawberries and spider plants reproduce by sending out special side shoots called runners.

Where the runner touches the ground, a new plant will grow.

S1 to N4 Bio Textbook

Task 1:�Read Pages 155-156 and answer Question 1 on Page 156.��Task 2:� Page 158 Q1-3

Germination

Todays’ Activities

1. Check your Nat 4 LO1 feedback sheet. What do you need to do to pass?
2. Make improvements to your investigation write up
3. Using your knowledge of seed germination and the internet, create a step by step guide on a piece of A4 paper to explain how to grow a seed.

Include: diagrams, conditions needed for germination, instructions on watering etc.

• Plant your seed!

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