Contexts:
1) Combating Climate Change - Methane Reduction in Cows
The beef and dairy industry in New Zealand contributes greatly to our economy. However, as we learn more about climate change, pressure is being placed on scientists to investigate how we can reduce our contribution to the emission of greenhouse gases such as carbon dioxide and methane. Although much discussion has taken place regarding the amount of carbon dioxide emissions are produced through activities such as transportation and manufacturing, attention is now focusing on methane which makes up 48% of our current emissions and .
Methane is produced by microbes in the fore-stomach of ruminants, from the plants that animals eat (see What is enteric fermentation?). Methane is relatively a short-lived gas that decays back into carbon dioxide with a half-life of around 12 years. But while methane is in the atmosphere, it makes a powerful contribution to the overall warming effect of greenhouse gases because it is much more effective at absorbing heat radiation than carbon dioxide.
Current estimates are that emissions of methane to date have contributed almost 40 percent of the total warming effect from all human activities.
Non GM approach - Changing Diet
GM approach - HME Ryegrass
Question 1
After watching the two videos above, discuss the implications of using GM and non-GM techniques to tackle the climate change concerns associated with beef and dairy farming in NZ. In your response include:
- how genes are manipulated to produce a more desirable food source for cows
- how the health and survival of ryegrass is affected
- How the health and survival of cows has been considered
- implications for the productivity of dairy farms and how this related to survival of humans
- ecological implications of introducing transgenic ryegrass into the environment
2) Food Security
The following is adapted from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5790416/
The American Food and Agricultural Organisation projects the global population to grow to approximately 9.7 billion by 2050 and further to an estimated 11 billion by 2100. Current agricultural practices alone cannot sustain the world population and eradicate malnutrition and hunger on a global scale in the future. The FAO estimates that despite a significant reduction in global hunger, 653 million people will still be undernourished in 2030.
Additionally, studies depict the top four global crops (soybean, maize, wheat and rice) are increasing in production at approximately half the rate required for the agriculture industry to sustain the global population in 2050. Compounded with other problems such as improved nutritional standards in the burgeoning lower-middle class and projected loss in arable land (from 0.242 ha/person in 2016 to 0.18 ha/person in 2050) due to degradation and accelerated urbanization, rapid world population expansion will increase demand for food resources.
Producing food crops is a complex job. Considerations such as soil type, water availability, pest control, competition (weeds), growth rate and nutrient composition are all important factors when managing crops. Some crops are planted for human consumption and some are planted to produce feed/silage for animals grown for consumption. In each case, genetic modification can be looked to to solve some of the complexities of meeting the increasing demand for nutrient rich foods.
a) Transgenesis and bt-crops
The video below helps to identify some of the issues related to food security. By comparing the implications of traditional farming methods which include the use of pesticides to the implications of using transgenesis to incorporate pest resistance into plants directly, provide your analysis of the short-term and long-term risks and benefits of each.
Question 2
After watching the video above and conducting your own research (a starting point - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5790416/), discuss the implications of using GM and non-GM techniques to tackle challenges in growing crops. In your response include:
- how genes are manipulated to produce a more desirable plant-based crops.
- how the health and survival of crops like corn are affected
- how the health and survival of animals eating GM plants may or may not be affected
- ecological implications of introducing transgenic crops into the environment
- an analysis of the short-term and long-term implications for the rate and direction of evolution of target species.
- Justify a method for managing crops over one decade to reduce the risk of pest populations rebounding.
b) Biofortification - Solving iron deficiency and Vitamin A deficiency by improving rice
Responding to poverty, malnutrition and the growing demand for protein, biofortification is being looked to as a means of improving health through dietary means. The following videos will introduce you to the biotechnology and issues surrounding the use of transgenesis in rice.
Iron Deficiency/Anaemia
Vitamin A deficiency
Question 3
After watching the videos above and conducting your own research, discuss the implications of using GM and non-GM techniques to tackle challenges in treating malnutrition in poverty stricken and developing countries. In your response include:
- how genes are manipulated to produce a more desirable plant-based crops.
- how the health and survival of people eating GM plants may or may not be affected
- ecological implications of introducing transgenic crops into the environment
- an analysis of the short-term and long-term implications for the rate and direction of evolution of target species.
- Analyse the scientific and ethical considerations presented to the public to provide arguments for and against the use of genetic modification as a means of solving malnutrition.
(Extension: An alternative avenue to explore could be to elaborate on these examples to justify the use of genetic modification to meet the increasing demand for protein. How could plant-based biofortification tackle solutions to malnutrition while responding to the environmental issues associated with animal protein production in agriculture?)
For this context you are to integrate your knowledge of traditional selective breeding techniques to outline how ancestral domesticated and modern sheep have been selected for.
Mouflon (11000 BCE) Merino (1600 CE)
Above - From wild ancestors to domesticated sheep, explain which traits were amplified and which traits were bred out of the sheep. With limited technology, how did shepherds achieve the outcomes they desired?
Below - With the movement of sheep from the old world to the new world, different considerations were necessary to take advantage of land that was unsuitable for farming crops, but also challenging for sheep.
Corriedale Sheep (1903 CE)
Question 4
Discuss the techniques involved in the creation of both marino and corriedale sheep varieties. Incorporate how selective breeding, hybridization, and genetic screening are now used to manage biodiversity and improve upon traditional methods. In your response include:
- how genes are manipulated to produce a more desirable sheep varieties.
- how the health and survival of sheep are affected (positively and negatively)
- an analysis of the short-term and long-term implications for the rate and direction of evolution of target species.
- a justification as to how selective breeding can be done while reducing the risk and potential consequences of inbreeding depression.
https://archive.org/details/cu31924003169814/page/n9
Corriedale features
http://www.nzsheep.co.nz/index.php?page=corriedale
Valuable traits
https://www.stuff.co.nz/business/farming/77377735/using-genetic-traits-for-profitability-in-sheep
Explore Corriedale 2.0
http://www.wilfieldsheepstud.co.nz/about.html
Uncomfortable Family Trees - latest technology in breeding. Explain how genomic analysis can be used to assist in selective breeding. What are the advantages?
4) Gene editing using CRISPR
Feel free to use this amazing website to explore gene editing technologies associated with CRISPR
https://unlockinglifescode.org/crispr-teaching-tools
ELIMINATING MALARIA
Can we use CRIPSR to edit genes to get rid of malaria?
Question 5
Discuss the techniques involved in the genetic manipulation of mosquitos to prevent the transmission of the malaria parasite. In your response include:
- how genes are manipulated to produce a mosquito that no longer acts as a vector
- identify the challenges of producing a wild population of mosquitos incapable of transmitting malaria.
- explain how gene drives can be used to overcome the challenges
- elaborate on the short-term and long-term implications for the rate and direction of evolution of mosquito species
- provide an analysis of the short-term and long-term implications for the rate and direction of evolution of the parasite and/or humans
Helpful Videos
Another video
No comments:
Post a Comment