Nutrition and Energy in Plants

Key Issues

Titles

Chapters

• describe how photosynthesis can be increased by providing more CO2; more light; a higher temperature
• During photosynthesis: light energy is absorbed by a green substance called chlorophyll which is found in chloroplasts in some plant cells, this energy is used by converting carbon dioxide and water into sugar (glucose), oxygen is released as a by-product
• explain and interpret data about plant growth in the presence or absence of these minerals
• explain how competition between plants for light can reduce crop yields
• explain how the products of photosynthesis are used by a plant
• explain simple data about plant growth in the presence or absence of these minerals
• explain that active transport can move substances from low concentrations to high concentrations using energy from respiration
• explain that glucose is converted and stored as starch
• explain that the glucose made by photosynthesis is transported as soluble sugars but is stored as insoluble starch
• explain the effects of limiting factors on the rate of photosynthesis (CO2, light, temperature) and how crop scientists use this understanding to increase plant yields
• Factors affecting the rate of photosynthesis
• Factors Limiting Photosynthesis
• For healthy growth plants need mineral ions including: magnesium - which is needed for chlorophyll production
• For healthy growth plants need mineral ions including: nitrate - for producing amino acids which are then used to form protein
• Glucose
• interpret data on research on factors affecting plant yields.
• know that photosynthesis is a key process which is essential to life including investigations which show that light, carbon dioxide, and chlorophyll are needed for photosynthesis to take place
• know that photosynthesis is a key process which is essential to life including that oxygen and starch are produced by photosynthesis
• Lack of Necessary Minerals
• Light, temperature and the availability of carbon dioxide interact and in practice any one of them may be the factor that limits photosynthesis
• Minerals Needed By Plants
• Photosynthesis Equation
• Photosynthesis is summarised by the equation: carbon dioxide + water (+ light energy) -> glucose + oxygen
• Plant cells use some of the glucose produced during photosynthesis for respiration
• Plant roots absorb mineral salts including nitrates needed for healthy growth
• plants require specific minerals for healthy growth limited to calcium for cell walls
• plants require specific minerals for healthy growth limited to magnesium for chlorophyll formation
• plants require specific minerals for healthy growth limited to nitrogen as nitrates for amino acids and protein formation
• Process of Photosynthesis
• Rate of Photosynthesis
• recall the names of important minerals; nitrates, phosphates, potassium and magnesium
• state that minerals are taken up into roots by active transport
• state that photosynthesis occurs mainly in the leaves
• state that plants also need minerals, which are found in the soil, for healthy growth
• state that plants grow faster in the summer because of light and warmth
• state that plants make glucose and starch by a process called photosynthesis
• state that plants need carbon dioxide, water, light and chlorophyll to carry out photosynthesis
• state that plants release energy by respiration: oxygen is used from the air
• state that plants release energy by respiration: starch is broken down
• state that plants release energy by respiration: water and carbon dioxide are waste products
• state that plants require magnesium (for chlorophyll)
• state that plants require nitrates (for proteins which are needed for cell growth)
• state that plants require phosphates (for healthy growth, including root growth)
• state that plants require potassium (for healthy growth and flowering)
• state that these minerals are absorbed in solution by the roots
• state the balanced symbol equation for photosynthesis: 6CO2 + 6H2O + light + chlorophyll -> C6H12O6 + 6O2
• state the equation to describe photosynthesis: carbon dioxide + water + light + chlorophyll -> glucose + oxygen
• The glucose produced in photosynthesis may be converted into insoluble starch for storage
• The rate of photosynthesis may be limited by low temperature
• The rate of photosynthesis may be limited by shortage of carbon dioxide
• The rate of photosynthesis may be limited by shortage of light
• The symptoms shown by plants growing in conditions where mineral ions are deficient include stunted growth if nitrate ions are deficient
• The symptoms shown by plants growing in conditions where mineral ions are deficient include yellow leaves if magnesium ions are deficient
• the word equation for photosynthesis
• understand that plants respire, including the exchange of oxygen and carbon dioxide through the stomata of the leaf of a plant during the day and during the night
• using data, explain how high rates of respiration can reduce plant yields