5a. Food Production 3/14/11 3:52 PM

5. Use of Biological Resourcesa. Food Production

Crop plants5.1 describe how glasshouses and polythene tunnels can be used to increase the yield of certain crops

5.2 understand the effects on crop yield of increased carbon dioxide and increased temperature in glasshouses

5.3 understand the use of fertiliser to increase crop yield

5.4 understand the reasons for pest control and the advantages and disadvantages of using pesticides and biological control with crop plants

Microorganisms5.5 understand the role of yeast in the production of beer

5.6 describe a simple experiment to investigate carbon dioxide production by yeast, in different conditions

5.7 understand the role of bacteria (Lactobacillus) in the production of yoghurt

5.8 interpret and label a diagram of an industrial fermenter and explain the need to provide suitable conditions in the fermenter, including aseptic precautions, nutrients, optimum temperature and pH, oxygenation and agitation, for the growth of microorganisms

Fish farming5.9 explain the methods which are used to farm large numbers of fish to provide a source of protein, including maintenance of water quality, control of intraspecific and interspecific predation, control of disease, removal of waste products, quality and frequency of feeding and the use of selective breeding.

5.1 Glasshouses 3/14/11 3:52 PM

5.1 describe how glasshouses and polythene tunnels can be used to increase the yield of certain crops

Watch the clip in class: “Plant Growth in Greenhouses”http://www.yteach.ie/index.php/resources/conserve_optimum_paraffin_yield_carbon_dioxide_water_light_temperature_leaf_t_page_9.htmlAfter you have watched the animation, answer the questions below:1. How do paraffin heaters in greenhouses increase yield of crops?

2. What other factor would the paraffin heaters affect?

Watch the second clip: “The advantages of greenhouse cultivation”http://www.yteach.ie/page.php/resources/view_all?id=humus_winter_crop_spring_crop_eutrophication_weed_rhizome_runner_herbicide_crop_rotation_hydroponics_fertilization_eutrophication_cultivation_page_6&from=searchListen the clip once, then on the second time through answer the questions below:1. What environmental factor is eliminated by growing crops in a greenhouse.

2. What external factors are the plants not subjected to?

3. What is hydroponic cultivation and what is it’s advantage?

RevisionIn the table below:

1. List five conditions, which will increase the rate of photosynthesis.

2. How could each of these conditions be controlled in a glasshouse (or polythene tunnel).

Condition Describe how the condition could be controlled to increase crop yield

Question:1. A gardener grew plants in a greenhouse as shown below.

(a) Give TWO conditions in the greenhouse, which could limit the rate of photosynthesis in the plants. (2)

(b) Explain why the use of additional light may not lead to an increase in the growth of the plants. (2)

2. Early crops of tomatoes are produced in greenhouses heated at 15–22°C and with the level of carbon dioxide increased from its normal level of 0.03% to 0.1%.(a) Explain why the extra carbon dioxide is provided only during daylight hours. (1)

(b) Suggest ONE other factor which might have to be increased to obtain an even greater yield when the carbon dioxide level is raised above 0.1%. (1)

(c) Explain how increasing the carbon dioxide levels leads to an increased yield of tomatoes. (1)

3. The graph below shows the effect of increasing temperature on the rate of photosynthesis of green leaves.

(a) At what temperature is the rate of photosynthesis at its maximum value? (1)

(b) Estimate the temperature at which photosynthesis will stop. (1)

(c) Suggest ONE reason why photosynthesis stops at higher temperatures. (1)

5.2 Crop Yield 3/14/11 3:52 PM

5.2 understand the effects on crop yield of increased carbon dioxide and increased temperature in glasshouses

RevisionWhat is the effect of increasing carbon dioxide levels and temperature on the rate of photosynthesis?

Explain why an increase in carbon dioxide level and temperature results in an increase in crop yield (production)?

1. You should recognize the graph below from when you studied:2e. Plant Nutrition

(a) Which factor is limiting the rate of photosynthesis between points X and Y? Explain your answer. (2)

(b) Account for the shape of the graph between points P and Q.

(c) What might the final limiting factor be when the CO2 has been increased to 0.5%?

2. The graph below shows how the rate of photosynthesis varies with light intensity at two different carbon dioxide concentrations.

(a) Use the graph to find the rate of photosynthesis when the light intensity is 3000 lux and the CO2 concentration is 0.1%. (1)

(b) Use the graphs to explain what is meant by a limiting factor. (2)

5.3 Fertilisers 3/14/11 3:52 PM

5.3 understand the use of fertiliser to increase crop yield

Watch the clip in class: “Effects of artificial Fertilisers”http://www.yteach.ie/index.php/resources/biocoenosis_biosphere_ecosystem_energy_eutrophication_photosyntesis_species_respiration_environment_transpiration_biogeochemical_cycles_organic_compounds_t_page_23.html1. Name the mineral put in fertilizers.

2. What can happen if too much fertilizer is added?

Revision2e. Plant NutritionName four minerals required by plants, state their function and the symptoms shown by a plant if they do not have the minerals (you learnt two of these in 2e. Plant Nutrition).

Mineral Function Deficiency Symptom

Questions1. The bar chart below shows the average yearly yield of grain given by six plots of wheat in the Broadback Field at Rothamsted between 1852 and 1967.

Plot Treatment1none2nitrogen only3nitrogen and phosphorus4nitrogen, phosphorus and potassium5farmyard manure6nitrogen, phosphorus, potassium, sodium and magnesium (complete

inorganic fertiliser)

(a) In what form do plants absorb nitrogen? (1)

(b) Calculate the yield of grain given by plot 5 as a percentage of plot 1. (1)

(c) What is the function of nitrogen in plants? (1)

2. State the importance of the minerals nitrogen and magnesium, to the healthy growth of plants. (2)

3. The graph below shows how the addition of fertiliser affects crop yield.

Why is it not economical for a farmer to add more than 28 kg of fertiliser per hectare to the potato crop? (1)

5.4 Pest Control 3/14/11 3:52 PM

5.4 understand the reasons for pest control and the advantages and disadvantages of using pesticides and biological control with crop plants

Ref:Pg. 138 13.8 “Malaria is difficult to control – Biological Control”

Pg. 178 16.18 “Pesticides help to increase crop yields” 16.19 “Pesticides can harm the environment”

In class watch the clips:“Elimination of Weeds”http://www.yteach.ie/page.php/resources/view_all?id=biocoenosis_biosphere_ecosystem_evolution_energy_species_gene_homeostasis_generation_population_seat_succession_environment_biodiversity_page_2&from=search

“Elimination of pests”http://www.yteach.ie/page.php/resources/view_all?id=biocoenosis_biosphere_ecosystem_evolution_energy_species_gene_homeostasis_generation_population_seat_succession_environment_biodiversity_t_page_6&from=search

1. Why do farmers remove non-crop species from a field of crops?

2. How can the weeds/ pests be removed?

3. What is an associated (“knock-on”) effect of removing weeds (or other pest species)?

RevisionWhy do farmers need to control pests?

Define the term ‘pesticide’.

Define the term ‘biological control’.

Make a list of the advantages and disadvantages of removing pests:Advantages:

Disadvantages:

5.5 Yeast & Beer Production 3/14/11 3:52 PM

5.5 understand the role of yeast in the production of beer

Ref:Pg. 152-153 14.8 “Yeast is used for making alcohol”

RevisionThe best known fermentation reaction is the anaerobic respiration of glucose by yeast.Often known as alcoholic fermentation.View the clip in class: “Alcoholic Fermentation”http://www.yteach.ie/index.php/resources/enzyme_reaction_specific_selective_alcoholic_fermentation_protein_page_8.html

“The Process of Alcoholic Fermentation”http://www.yteach.ie/page.php/resources/view_all?id=alcohol_ethanol_fermentation_synthesis_reaction_methanol_sucrose_page_2&from=search

What nutrients are going to need to be present in the culture medium for yeast to grow and reproduce?

Write out the word equation for alcoholic fermentation.

What is the name of the substrate used by the yeast?

What are the waste products produced during the process?

Explain what would happen the yeast if the alcohol concentration in the medium increased to over 9%.

What is the most favourable temperature for fermentation?

What would fermentation stop above 50C?

5.6 Investigating CO2 Production 3/14/11 3:52 PM

5.6 describe a simple experiment to investigate carbon dioxide production by yeast, in different conditions

Questions:1. A student investigated the process of fermentation using the apparatus shown.

(a) The apparatus was used in conditions which encouraged fermentation. Highlight the temperature which would result in the fastest fermentation. (1)

very hot (100ºC) hot (80ºC) warm (40ºC) cool (20ºC)

(b) Why was it important to have a tight seal between the test tube and the balloon? (1)

2. Two test tubes, A and B, were set up and kept at the same temperature.Tube A contained 2g of yeast and 5cm3 of fruit juice.Tube B contained 2g of yeast, 5cm3 of fruit juice and 5g of sugar.The results after 24 hours are shown below.

(a) Which gas caused the balloons to inflate? (1)

(b) Explain the difference between the results for tube A and test tube B. (1)

(c) After 24 hours of fermentation, the contents of each tube had changes.(i) What would have increased in the tubes? (2)

(ii) What would have decreased in the tubes? (1)

(d) Using the same apparatus, suggest how the student could(i) measure the rate of fermentation. (2)

(ii) make sure that the results were reliable (1)

(e) After 48 hours, all fermentation stopped in both test tubes. Suggest one reason for this. (1)

In an investigation of fermentation, a small test tube was filled with grape juice and yeast.The test tube was put into a measuring cylinder.The measuring cylinder was then put into a water bath kept at 40ºC, the best temperature for fermentation.The apparatus was left for 120 minutes.In this time, the yeast was used up all nutrients.

Complete the table by writing either yes or no in each box. (4)

Highlight in the list the time when the number of yeast cells in the apparatus was at its lowest.

(1)O minutesBetween 0 and 60 minutes60 minutes120 minutes

Explain what would have happened if the water bath has been kept at20ºC (1)

80ºC (1)

5.7 Yogurt 3/14/11 3:52 PM

5.7 understand the role of bacteria (Lactobacillus) in the production of yoghurt

Ref:Pg. 154 14.10 “Bacteria are used to make yogurt and cheese”

RevisionList some of the characteristics of the Bacterial Kingdom

View the clip in class: “Yoghurt”http://www.yteach.ie/page.php/resources/view_all?id=enzyme_reaction_specific_selective_alcoholic_fermentation_protein_t_page_29&from=search1. Name the sugar found in milk.

2. What do yoghurt bacteria produce from milk sugars? What effect does this have on taste of yoghurt?

“Where does yoghurt come from”http://www.yteach.ie/index.php/resources/asepsis_dna_recombination_dna_insulin_somatostatin_transgenic_organism_somatotrophin_fermentation_pasteurization_malting_milling_whirling_brewing_maturation_filtration_page_4.html1. Where does yoghurt come from?

2. How is milk pasteurized?

3. Why is the milk pasteurized?

4. Name the bacteria (you only need one name) added to the pasteurized milk?

5. Why is the milk cooled to 47C?

6. What is the optimum range of temperature for fermentation?

7. What effect do you think the drop in pH will have on the enzymes in the bacteria?

8. Why will the end product of yoghurt need to be stored at 4C?

5.8 Fermenters 3/14/11 3:52 PM

5.8 interpret and label a diagram of an industrial fermenter and explain the need to provide suitable conditions in the fermenter, including aseptic precautions, nutrients, optimum temperature and pH, oxygenation and agitation, for the growth of microorganisms

Ref:Pg. 155-156 14.12 “Fungi making antibiotics”

In class view the clip: “The Structure of the Fermenter”http://www.yteach.ie/page.php/resources/view_all?id=asepsis_dna_recombination_dna_insulin_somatostatin_transgenic_organism_somatotrophin_fermentation_pasteurization_malting_milling_whirling_brewing_maturation_filtration_t_page_20&from=search

Go through each part of the fermenter, discuss and take a note of the function.

Second clip: “Biofermenters”http://www.yteach.ie/page.php/resources/view_all?id=asepsis_dna_recombination_dna_insulin_somatostatin_transgenic_organism_somatotrophin_fermentation_pasteurization_malting_milling_whirling_brewing_maturation_filtration_t_page_19&from=searchYou do NOT need to remember details from this clip.

Questions1. Six of these flasks were used to investigate fermentation by two different types of yeast, A and B. The flasks contained different mixtures.

All the flasks were kept at 40ºC.After 3 days, the number of yeast cells in each flask was counted.An increase in the number of yeast cells shows that fermentation has taken place.The main conclusions of this investigation are shown in the table.

(a) Which types of yeast, A or B, only used glucose as food? (1)

(b) What evidence in the table shows that yeast B can change starch into glucose? (2)

(c) Suggest how yeast B changes starch into glucose. (1)

(d) The mixture of yeast A and glucose fermented. The fermentation stopped after one week. Suggest TWO possible reasons why this happened. (2)

2. The diagram below shows a fermenter used to grow micro-organisms

(a) Describe how the temperature is kept constant in the fermenter. (2)

(b) Name ONE other factor that must be kept constant in the fermenter. (1)

(c) Explain why air is pumped into the fermenter. (2)

(d) Explain what would happen to the growth of micro-organisms in the fermenter if the paddles stopped working. (3)

(e) Suggest why steam is used to sterilise the fermenter rather than disinfectants. (2)

5.9 Fish Farming 3/14/11 3:52 PM

5.9 explain the methods which are used to farm large numbers of fish to provide a source of protein, including maintenance of water quality, control of intraspecific and interspecific predation, control of disease, removal of waste products, quality and frequency of feeding and the use of selective breeding.

Ref:Pg. 180 16.22 “Fisheries need careful management”

In class watch the clip: “Fish Farming”http://www.yteach.ie/page.php/resources/view_all?id=biocoenosis_biosphere_ecosystem_evolution_energy_species_gene_homeostasis_generation_population_seat_succession_environment_biodiversity_t_page_16&from=search 1. List the advantages of fish farming.

2. List the disadvantages of fish farming.

*You will take notes on each of the following in class:Maintenance of Water Quality

Control of Intraspecific Predation

Control of Interspecific Predation

Control of Disease

Removal of Waste products

Quality and Frequency of Feeding

Selective Breeding