RHS Level 2 Certificate

Week 16 – Review Week: Soil nutrients, limiting factors and relative humidity. Study Skills – active learning and mind mapping.

Learning objectives

Identify three active approaches to study State three basic principles of mind mapping. Draw a simple mind map for a macro nutrient Explain the effects on plant growth of nitrogen,

phosphorous, potassium, calcium and iron in normal quantities in the soil and in deficiency.

Explain the effect of air temperature on relative humidity and how RH can be increased or decreased

Explain the law of limiting factors and apply this to photosynthesis and respiration to explain increases and decreases in these processes.

Being an active learner Active learners are engaged with their own

learning – deliberately seeking new strategies, formulating their own questions, sharing ideas and understanding.

A more interesting and engaging way to learn – and more effective.

Learning is not something that is done to you – it is something that you do yourself.

The more you work with information and apply it, the better your recall and understanding will be.

Mind Mapping basics A visual record of the connections between ideas

and concepts, as well as the concepts themselves.

Presents information in the way that the mind perceives it, as a hierarchy with interconnections – not a linear, left to right approach.

Uses colour, humour, images to make memories and connections more powerful

The real benefit is making the mind map – actively seeking to make connections between ideas and information.

Lots of computer programs exist for this – but all you need is paper and colour pens and your information and creativity.

Stages to mind mapping Chose a topic – this goes in the centre of a

landscape page. Keep it simple. Add colour/pictures.

Select/identify the basic organising ideas Link these to the topic with thick, coloured curvy

lines. One colour per BOI. Add images. Thinner lines branch off the basic ideas lines for

the component/supporting information and ideas. Keep words to a minimum – they trigger memory.

Use arrows and lines to show interconnections. Bubbles, colour, highlights and pictures. Make it fun!

Main Plant macro-nutrients

Nitrogen – essential for production of chlorophyll and all metabolic processes. Deficiency causes chlorosis, older leaves first.

Phosphorous – root development, germination, photosynthesis. Deficiency – small, purple or blue tinged leaves.

Potassium – fruiting and flowering, cold and drought hardiness. Deficiency – brown, curled leaf edges, poor fruiting.

Other nutrients

Calcium – essential for cell wall formation; usually plant deficiency is pH or drought related not an absence in the soil. Low pH (acidity) makes Ca unavailable. Deficiency – bitter pit in Apples, blossom end rot in Tomatoes.

Iron – essential for chlorophyll; immobile in the plant; usually deficiency is pH related not due to lack in the soil. Alkaline soils may show iron deficiency. Deficiency – interveinal chlorosis, young leaves first.

Relative Humidity The warmer air is the more water vapour it

can hold before it becomes saturated and the water begins to precipitate out.

Cooler air can hold less water vapour and becomes saturated with a smaller amount of water vapour.

Relative humidity measures the temperature of the air and what proportion of the total amount of water vapour that the air at that temperature can hold is actually present.

Limiting Factors Where a chemical reaction is dependent on a

number of factors, the factor in least supply will limit the speed/efficiency of the reaction.

Photosynthesis is the process in chlorophyll of storing energy from the sun in carbohydrates.

Cellular respiration is the process (in the mitochondria of cells) of releasing that stored energy

Both are complex chemical reactions. Their speed and efficiency can be limited by a number of factors.

Learning outcomes

Identify three active approaches to study State three basic principles of mind mapping Draw a simple mind map for a macro nutrient Explain the effects on plant growth of nitrogen,

phosphorous, potassium, calcium and iron in normal quantities in the soil and in deficiency.

Explain the effect of air temperature on relative humidity and how RH can be increased or decreased

Explain the law of limiting factors and apply this to photosynthesis and respiration to explain increases and decreases in these processes.