Testing a leaf for starch is a common experiment in biology classrooms, as it allows students to understand the process of photosynthesis and how plants use energy. In this lab report, we will outline the materials and methods used, describe the results of the experiment, and discuss the implications of these results.
Materials:
- Fresh leaf from a green plant
- Iodine solution
- Beaker
- Test tube
- Glass stirring rod
- Dropper
- Paper towels
Methods:
- Obtain a fresh leaf from a green plant and gently wash it with water to remove any dirt or debris.
- Fill a beaker with water and add a few drops of iodine solution.
- Use a dropper to place a small drop of the iodine solution onto the leaf.
- Observe the color of the iodine on the leaf. If the leaf contains starch, the iodine will turn blue or black. If the leaf does not contain starch, the iodine will remain yellow or orange.
- Repeat the process with a few additional drops of iodine to confirm the results.
- If necessary, use a glass stirring rod to scrape a small piece of tissue from the leaf and place it in a test tube. Add a few drops of iodine solution to the test tube and observe the color change.
Results:
In our experiment, we found that the iodine turned blue or black when applied to the leaf, indicating the presence of starch. When a small piece of tissue was placed in a test tube and mixed with iodine solution, the solution also turned blue or black. These results suggest that the leaf we tested contains starch.
Discussion:
Starch is a complex carbohydrate that plants use to store energy. It is produced during photosynthesis, when the plant uses energy from sunlight to convert carbon dioxide and water into glucose. The glucose is then converted into starch and stored in the plant's tissues, such as leaves, stems, and roots.
The presence of starch in the leaf we tested confirms that the plant is able to carry out photosynthesis and produce glucose. This is important for the plant's survival, as it allows the plant to store energy for times when sunlight is not available, such as at night or during periods of low light intensity.
Overall, testing a leaf for starch is a simple and effective way to understand the process of photosynthesis and the role of starch in plant metabolism. It also helps students learn how to use scientific equipment and follow experimental procedures, which are important skills for any aspiring scientist.
Demand Function, Determinants of Demand
This increased demand for housing. The converse is also true. With most goods, there is a positive relationship between demand and the income of the buyer. Two commodities are said to be a substitute for one another if they satisfy the same want of an individual and the change in the price of one commodity affects the demand for another in the same direction. When the price of bread increases, it causes a decrease in demand for butter. Conversely, when quantity falls, the curve shifts to the left, indicating less demand for a given price.
What are the Determinants of Market Demand?
As per the consumer's expectations, if there is a decrease in the prices of goods or an increase in the income of an individual, it will automatically result in an increase in the demanded quantity. As a result, current demand increases, shifting its curve to the right. However, when income decreases, the demand for inferior goods increases. Thus, demand is only the desire which is backed up by the willingness and power to pay. An increase in the population indicates an increase in potential demand. Such considerations make some consumers not only look at current prices when deciding to buy. On the contrary, if the prices are expected to fall in the future the consumer will postpone their purchase with a view to avail benefits of lower prices in the future, especially in case of nonessential goods.
10 Determinants Of Demand: What, Definition, Example [2021]
Conversely, when consumers expect future prices to fall, they delay buying. For example, tea and coffee, jowar and bajra, and groundnut oil and sunflower oil are substitute to each other. Moreover, determining economic demand is one of the primary expenditures of companies and businesses. Movement along the curve Vs a shift in the curve Meanwhile, changes in non-price determinants also cause changes in quantity. Coal, electricity etc, are examples of composite demand.
Quantity Demanded: Definition, How It Works, and Example
Two of the biggest factors that influence how elastic demand is in relation to price are the availability of substitutes and whether the item is a necessity or a luxury. Cross demand refers to the relationship between the quantity demanded of one good say 'x' good and price of related goods say 'y good , other things being equal. Similarly, when the selling or cost price decreases, people would probably want to buy more from that company. Producers will increase supply if customers desire a good and are ready to pay more for it. We need to understand the meaning of determinants and types of demand. Further, there are 2 things to note about normal and inferior goods.
