We all know that in autumn and/or fall season, the leaves start to change color from green to red, yellow, and brown. The mixture of red, purple, orange and yellow is the result of chemical processes that take place in the tree as the seasons change from summer to winter. My 5-year-old kid always ask me “Why and how do leaves change colors during fall?”
To explain this, let us first understand the function of leaves. The food-making process takes place in leaves in numerous cells containing chlorophyll, which gives the leaf its green color. Chlorophyll has a vital function: it captures solar rays and uses the resulting energy in the manufacture of the plant’s food — simple sugars which are produced from water and carbon dioxide. These sugars are the basis of the plant’s nourishment — the sole source of the carbohydrates needed for growth and development. In their food-manufacturing process, the chlorophyll break down, thus are being continually “used up”. During the growing season, however, the plant replenishes the chlorophyll so that the supply remains high and the leaves stay green.
How plants make food during fall season without chlorophyll pigments?
During fall, because of changes in the length of daylight and changes in temperature, the leaves stop their food-making process. The chlorophyll breaks down, the green color disappears, and the yellow to orange colors become visible.
The steps below describe how the leaves change color during fall/autumn season:
Growing season of plants
Color of leaves are green due to chlorophyll pigments
Lack of sunlight energy
Degradation of chlorophyll pigments
The pigments carotenoids and anthocyanins that have been present (along with the chlorophylls) in the cells all during the leaf’s life begin to show through. These provide colorations of yellow, brown, orange, and purple colors, respectively.
A fun and educational video by SciShow Kids explains why do leaves change color in fall?
I have mentioned below a science experiment that describe the leaf color changing phenomenon in detail.
Suggested science experiment books
Water is essential for life. It covers 2/3 of the earth’s surface and every living thing is dependent upon it. The human body is comprised of over 70% water, and it is a major component of many bodily fluids including blood, urine, and saliva. Water – with its formula H2O – is the only inorganic compound existing in its solid, liquid and gaseous physical state under natural conditions. Water serves as a medium for the transformation of highly complex organic molecules that form the basis for life processes. The solid state of water is known as ice; the gaseous state is known as water vapor (or steam). The units of temperature (formerly the degree Celsius and now the Kelvin) are defined in terms of the triple point of water, 273.16 K (0.01 °C) and 611.2 Pa, the temperature and pressure at which solid, liquid, and gaseous water coexist in equilibrium.
The above video explains the important properties of water
Two important properties of water are discussed below:
What does it mean to say the water molecules is polar and is a “universal solvent?”
Water has high surface tension, what does this mean?
At an interface between air and water, a water molecule on the surface forms hydrogen bonds with other molecules around and below it, but not with air molecules above it. The unequal distribution of bonds produces a force called surface tension; this causes the water surface to contract and form a surprisingly tough film or ‘skin’.
Examples of surface tension:
Walking on water: Small insects such as the water strider can walk on water because their weight is not enough to penetrate the surface.
Floating a needle: A carefully placed small needle can be made to float on the surface of water even though it is several times as dense as water. If the surface is agitated to break up the surface tension, then needle will quickly sink.
Surface tension disinfectants: Disinfectants are usually solutions of low surface tension. This allow them to spread out on the cell walls of bacteria and disrupt them.
Soaps and detergents: These help the cleaning of clothes by lowering the surface tension of the water so that it more readily soaks into pores and soiled areas.
Washing with cold water: The major reason for using hot water for washing is that its surface tension is lower and it is a better wetting agent. But if the detergent lowers the surface tension, the heating may be unneccessary.
Why bubbles are round: The surface tension of water provides the necessary wall tension for the formation of bubbles with water. The tendency to minimize that wall tension pulls the bubbles into spherical shapes.
Surface Tension and Droplets: Surface tension is responsible for the shape of liquid droplets. Although easily deformed, droplets of water tend to be pulled into a spherical shape by the cohesive forces of the surface layer.
Let us explore some properties of water at surfaces with 2-3 activities. The materials needed are:
Fill a cup all the way to the top with water.
What do you think would happen if you were to add pennies to it?
Try adding pennies one at a time. What happens to the water in the cup?
How many pennies can you add without causing the water to overflow?
The video below demonstrates cohesion and surface tension in water. We add pennies into a full glass of water to show how surface tension will create a convex dome of water that rises above the rim of the glass. Surface tension is generated by cohesion and keeps an elastic tension between all the molecules in a liquid. The water has one of the highest surface tension.
Take some water with a straw and put a few drops on plastic wrap.
(a) What is the shape of the drop?
(b) Move a drop around with your straw. Does the drop change?
“Scientific inquiry starts with observation. The more one can see, the more one can investigate.” What are you waiting for, share with us your observations through comments.
Are you familiar with the chemical processes that govern our lives? Let us try to solve the questions about the study of the chemistry of living things and seek to understand the roles these play in developing and sustaining life.
What is Biochemistry?
The term biochemistry, which is the chemistry of life or the study of the processes behind all living organisms, was first coined in 1903 by Carl Neuberg, the father of biochemistry. Biochemistry is everywhere. General topics in biochemistry include: medicine, nutrition, molecular biology, and plant and animal biology. It deals with the structures and functions of cellular components such as proteins, carbohydrates, lipids, nucleic acids and other biomolecules.
Video: A brief and concise introduction to biochemistry. What is it? What does it involve? And why is it important?
Career prospects in Biochemistry
Although each occupation a biochemistry degree holder might work for has its own employment outlook, the statistics bureau predicts the employment of biochemists will increase 31 percent from 2010 to 2020, much faster than the average for all occupations. But as biochemists are in a small field, the growth will create only 7,700 new jobs over that time. The growth will be due to the demand for new medicines and medical procedures, cleaner energy, better crop yields and effective ways of protecting the environment.
2017 Salary Information for Biochemists
Biochemists earned a median annual salary of $82,180 in 2016, according to the U.S. Bureau of Labor Statistics. On the low end, biochemists earned a 25th percentile salary of $58,630, meaning 75 percent earned more than this amount. The 75th percentile salary is $117,340, meaning 25 percent earn more. In 2016, 31,500 people were employed in the U.S. as biochemists. The salary details of the year 2017 can be studied at https://www.payscale.com/research/US/Job=Biochemist/Salary.
As a scientific discipline in its own right, biochemistry has a major impact on all areas of the life sciences and biochemists are in high demand among employers. Keep following my website for next blog article on basics of biochemistry.
I have always been an avid nature explorer and my connection to the environment through nature was fueled by attending one of the wildlife educational program on Saturday, January 27, 2018 at Biodiversity Education Center at Coppell Nature Park, Texas (http://www.coppelltx.gov/bec). The center promotes and provides hands-on environmental education for both school and the community where the participants observe and learn about local flora, fauna, and environmental sustainability issues. One of the most reputable wildlife educators and party entertainers, Zooniversity been awarded with “Best of the Metroplex — Family Choice Award” seven times in a row in North Texas, conducted wildlife program on mammals at the center.
Participants exploring the trails at Coppell Nature Park
Mammals are among the most adaptable animals on the planet. They are found on every continent and in every ocean, and range in size from tiny bumblebee bats to enormous blue whales. All warm-blooded vertebrates (have backbones) including humans belong to mammals. They feed their young with milk and have a more well-developed brain than other types of animals.
The class reviewed mammal characteristics, unique habitats, adaptive anatomy, feeding, defense and weird animal behaviors. The insight on the “Zooniversity: Meet Mammals; Our Furry Friends” program is described below:
1. Basic study on characteristics/habitats of herbivores, omnivores, and carnivores.
Figure 1. Basic characteristics of herbivores, carnivores and omnivores explained.
2. Awesome experience of touching the fur/of mammals as coyote and skunks and studied/observed their skulls.
Figure 2. The skulls of mammals as coyote and skunk.
3. Adults and kids of all ages were welcomed to participate in hands-on experiments on blubber.
Figure 3. Hands-on experiment on “Blubber”
4. Kids were excited to draw and color the pictures of animals.
Figure 4. Kids engaged in drawing and coloring
Let us explore the nature and find ways to preserve and/or conserve our beautiful environment.
Do you have any such stories and/or involved in programs that instill love for the environment? Write to us!
The effects of science and its applications are seen everywhere nowadays, be it talking about life in Mars, internet, medicines….and lots more. With the knowledge of science, we learn to think logically and solve a problem. Communications, medicine, transportation, and almost everything you see around are because individuals have used their knowledge of science to create real life applications. Science is an extremely important field. Technology has given automation, while science has given the cure to so many diseases, raised awareness and made so many possibilities come close to us.
The main benefits of studying science are listed below:
Agriculture is extremely vulnerable to climate change and vice-versa. Climate changes as higher temperatures, changes in precipitation, soil moisture and sea levels contributes to global warming through ‘greenhouse gas’ (GHG) as carbon dioxide (CO2), methane (CH4), and nitric oxide (NO) emissions into the atmosphere. Various agricultural practices are contributing to climate change as well as will be affected by the climate change. Although there will be gains in some crops in some regions of the world, the overall impacts of climate change on agriculture are expected to be negative, threatening global food security. With an average global yield loss of upto 50% by 2050, the agriculture sector is at risk amidst global climate change (1), (2). In some of the tropical countries, agriculture is very important for economic development, poverty alleviation, employment and food security (3). How should we then overcome the setbacks and achieve breakthroughs in this area?
Thus, comes the need of an effective new agricultural practices and technologies, that can bestow to climate change mitigation and adaptation. These improvement should be in an order that will largely help the farmers to use them profitably, without any detrimental effects on the environment. However, without sound and appropriate governmental and institutional policies and regulations, the innovative technologies could not be put into practice.
The forms or methods for improving crop protection which in turn can prevent global warming issues are as follows:
A. The Crop Systems and Global Change Lab (CSGCL), Baltimore, http://www.ars.usda.gov/research/projects_programs.htm?modecode=12-45-25-00 applies systems theory to the solution of complex agricultural problems and to the development of computer-aided farm decision support systems and assessment tools for environmental study and analysis. It carries out research to improve the growth, yield and quality of crops in the face of climatic changes, through increased understanding of mechanisms controlling response and adaptation to CO2, light, water, temperature, and soil chemistry.
B. Introducing crop varieties/traits that confer tolerance to drought and heat, tolerance to salinity, and early maturation, through advances in breeding programs/biotechnology, in order to shorten the growing season and reduce farmers’ exposure to risk of extreme weather events. Attempts are in the direction to evolve varieties which respond positively in growth and yield to high CO2 and varieties with high fertilizer and radiation use efficiency. Plants are also being created that will use nitrogen more efficiently, reducing the need for added fertilizer and thereby lessening greenhouse gas (GHG) emissions.
C. Improvements in technologies related to conservation of natural resources: in situ moisture conservation, rainwater harvesting and recycling, efficient use of irrigation water, conservation agriculture, energy efficiency in crop production and irrigation and use of poor quality water. The suggested strategies are: characterization of biophysical and socioeconomic resources utilizing Geographic Information System (GIS) and remote sensing; integrated watershed development; developing strategies for improving rainwater use efficiency through rainwater harvesting, storage, and reuse; contingency crop planning to minimize loss of production during drought/flood years. (4), (5) Build up soil organic matter and prevent erosion by applying techniques such as conservation tillage, nutrient management and the use of reclamation varieties. Initiatives are undertaken in countries to develop ‘climate smart’ agricultural methods.
D. The government should concentrate on integrating national development policies into a sustainable development in agriculture that would lead to technology advances/adaptation. These strategic policies would not only improve the welfare of rural populations now, but they will also do a great deal to mitigate the future impacts of climate change.
By considering these options, what else according to you, are the advanced technologies adopted in the agricultural sector that would lead to crop improvement amid global climate change and inverse? What initiative(s) the government are taking and should need to take in order to have a global food security?
1. IPCC 2007 IPCC Summary for policy makers. Climate Change 2007. Cambridge: Cambridge University Press. pp.18.
2. Mendelsohn R. 2009. The impact of climate change on agriculture in developing countries Journal of Natural Resources Policy Research 1: 5–19.
3. Wheeler D. 2011. Quantifying vulnerability to climate change: Implications for adaptation assistance. Washington, D.C.:Center for Global Development. 49p.
4. Kapoor A. 2006. Mitigating natural disasters through preparedness measures. Proceedings of the International Conference on Adaptation to Climate Variability and Change, 5-7 January 2006, New Delhi, organized by Institute for Social and Environmental Transition and Winrock International India. 184 pp.
5. Venkateswarlu B, Shanker AK. 2009. Climate change and agriculture: adaptation and mitigation strategies Indian Journal of Agronomy 54 (2): 226-230.
My happiness lies in making others’ happy. I feel that happiness and joy multiplies once you share or give other’s the same.
What is that little spark which makes YOU feel happy? Please share…..
All breeding leads to genetic changes, but in recent decades, advances in the field of genetic engineering have allowed control over the genetic changes introduced into an organism. The process of genetic engineering is the targeted manipulation of a plant’s or animal’s DNA to modify specific traits, involving the incorporation of new genes from one species into a completely unrelated species. Crop plants, farm animals, and soil bacteria are some of the prominent examples of organisms that have been subject to genetic engineering. The crops or organisms being developed by such a process are known as Genetically Modified Crops or Genetically Modified Organisms (GMOs). The initial objective for developing plants based on GM organisms was to improve crop protection. The GM crops currently on the market are mainly aimed at an increased level of crop protection through the introduction of resistance against plant diseases caused by insects or viruses or through increased tolerance towards herbicides.
But the discussion of my present topic is:
Are Genetically Modified Crops/Food safe for human consumption?
The answer is YES, although there are still ongoing for and against debates over this issue. However, the U.S. National Academy of Sciences, the European Commission, the American Medical Association and the scientific academies of Britain, France and Germany reviewed the evidence and concur that existing GM foods are as safe and nutritious as conventional varieties. These organizations believe that genetic engineering and GE crops should be considered important options in the efforts toward sustainable agricultural production. http://www.geneticliteracyproject.org/wp/wp-content/uploads/2013/10/Nicolia-20131.pdf .
Global food production is facing several challenges such as climate change, population growth, and competition for arable lands. For this reason, conserving land to produce more food is a necessity for any long term plan. Biotechnology firms claim that transgenic crops promise bigger yields to create more efficient use of land, better resistance to weeds, pest and other diseases, , less use of herbicides and other pesticides, have better texture, flavor and nutritional value, and have a longer shelf life for easier shipping. In short, GM foods can create an essential sustainable way to feed the world. Read More