Why do ripened mangoes have a strong smell?

The smell of ripened mangoes is very strong. Why the smell is so strong. Let’s start some properties of fruit ripening. The fruit ripening signal is the sudden production of ethylene. Ethylene is the simple hydrocarbon gas produced in ripening fruit and released into the atmosphere. This ethylene signal causes developmental changes that result in fruit ripening. These developmental changes are triggered by the set of enzymes called hydrolases. Ethylene apparently ‘ turns on’ the genes that are transcribed and translated to make these enzymes. The enzymes then catalyze reactions to alter the characteristics of the fruit. The action of the enzymes causes the ripening responses. Chlorophyll is broken down and sometimes new pigments are made so that the fruit …

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Why does the stem colour change to brown as they grow older?

All the stems of plants and trees are green in colour when young. But why does the stem colour change to brown as they grow older? The stem of all plants is green due to the presence of hypodermal chlorenchyma in its cortex. But when the stem axis, especially the dicot stem axis, ceases to elongate and undergoes secondary growth. Its green colour disappears and becomes pale or dark brown in colour. The secondary growth is not only responsible for the change in surface colour but also contributes to the thickness of the axis due to the formation of the periderm. This is effected in the cortex by a lateral meristem called phellogen and the formation of secondary vascular tissues, …

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How does an unripe fruit turn sweet a few days after it is plucked?

Ripening is a physiological process involving the inclination of a variety of metabolic process, making the fruit sweeter and more palatable. Plants send unique ripening signals using hormones, most of the processes are enzymatically regulated and catalyzed. The process of fruit ripening is primarily regulated by a gaseous plant hormone called ethylene. This ethylene is produced and released by rapidly – growing plant tissues. growing tips of roots release it. Flowers, damaged tissue, and ripening fruit. Hence the act of picking matured green fruit can cause a wound which activates ethylene production and induce the ripening process. This phytohormone ethylene is said to regulate the expression of serveral genes involved in fruit ripening so as to modulate the activity of …

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Why are flowers not black in colour?

Is it possible the Black colour flower Sunlight is usually known as white light, Which is a combination of all the colours? When sunlight shines on an object, some of the light is absorbed, whereas the remaining light is reflected by the object. This reflected light gives the colour for that object. Most flowers in nature are varyingly and brightly coloured. the colour of a flower depends on the absorption and reflection of a certain colour by the petals of that flower. most of the plant parts including flower petals contain various pigments such as chlorophyll, carotene anthocyanin etc. River Rafting These pigments, depending on their concentration, absorb a certain wavelength of white light, and reflect the other wavelengths, which …

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Temperature Heat and Temperature Scale

Temperature is an objective measurement of how hot or cold an object is. It can be measured with a thermometer or a calorimeter. It is a means of determining the internal energy contained within a given system. Because humans easily perceive the amount of heat and cold within an area, it is understandable that temperature is a feature of reality that we have a fairly intuitive grasp on. Consider that many of us have our first interaction with a thermometer in the context of medicine, when a doctor (or our parent) uses one to discern our temperature, as part of diagnosing an illness. Indeed, temperature is a critical concept in a wide variety of scientific disciplines, not just medicine. Have you ever …

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Electricity is one of the most useful forms of energy. It is used to run various appliances suggestively Amazon music system, computer, refrigerator, heaters etc. they work only when electric current flows through them. Electrical energy can be transformed into several forms of energy. In a light bulb, electrical energy is transformed into heat and light energy. In a fan, it is transformed into mechanical energy. In a television, it is transformed into light and sound energy. The flow of electrons generate an electric current. Electricity has become an integral part of our daily life. It has simplified our lifestyle and has made us equipped with those technologies which will bring emails development and innovation in the near future. Daily …

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Food and Nutrition

Food is the basic requirement for survival of all living organisms. animals depend directly or indirectly on green plants to obtain food. The process of taking food and getting energy for it form growth and development is called nutrition. Energy is released when food substances present in living cells breakdown chemically through a process of oxidation. The Living WorldNature and Scope of BiologyPhysical Activity for good healthBalance Diet and Nutrition Autotrophic Nutrition The mode of nutrition in which organisms make food themselves from simple substance is called autotrophic nutrition. All green plants and some bacteria have an autotrophic mode of nutrition. Green plants prepare their food by the process of photosynthesis. Leaves are the food factories of plant and help …

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Science a Friend or An Enemy

Science is a blessing. It has added humans happiness in so many ways. By using the power of science, man has controlled nature. Science has made in possible things possible. But every coin has two sides. Science shows its evil side when it is used for destructive purposes. Science as a danger to life Inventions of science have become a danger to the life of human beings. Atom bombs, hydrogen bombs poisonous gas kill thousands of persons. Nuclear weapons threaten the very existence of mankind. Causes sickness factories are the product of science. Men work in factories. Machines make them dull. They live in an unhealthy atmosphere. They fall ill and ruin their health. Factories is spread poisonous gases which …

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