Measurements in plant growth

We can measure the growth of an organism by measuring its mass, length, height, width and area or volume. Over a period of time, sometimes it's possible to measure just one of an organism such as, the leaf of a plant, but this part must grow in proportion to the complete organism. In the case of seedlings, the number of leaves may be used as a growth indicator. Each of these growth indicators is known as a parameter of growth.
The pattern of growth of an organism would vary with the growth parameter that is used. In growth studies, the parameter used would depend on the type of organism. For example, we can measure the height of maize plant to estimate it's growth, but we cannot use the same parameter to assess the growth of a mouse. The ease of measuring a growth parameter will also determine its usage. Thus, area and volume measurements give an accurate picture of growth but are often difficult to measure and so are rarely used.
Mass and length are the most commonly used growth parameters since they are easy to measure. However, the results obtained may not be very accurate or reliable. For example, a seedlings grown in the dark increases in height more rapidly than a similar seedling in the sunlight but it is the seedling in the sunlight that shows greater growth in terms of an increase in protoplasmic material. Using measurements of mass may also be misleading. If an organism takes in large amount of water its mass may increase temporarily. This, however cannot be considered as growth. In most growth studies mass may be measured as wet mass or dry mass. Wet mass is the mass of the organism under normal conditions. It is not a reliable indication of growth.
Dry mass, is the mass of an organism after all the water in it has been removed. Although measuring growth in terms of dry mass is an accurate and reliable method, the organism get killed in the process. This means that it is not possible to measure growth in the same organism. To study growth by measuring dry mass, we must carry out the study on a large number of similar organisms.

Comments

Natural soil

Natural soils are influenced by rainfall and temperature,heavy rain causes the soil to become leached. High temperatures increase the rate of decomposition of organic matter in the soil, thereby lowering its humus content. Thus, climatic conditions tend to produce poor soils in the tropics and rich soils in the temperate regions. Besides climate and vegetation, the parent rock material also contributes to the quality of the soil. For example volcanic rocks tend to produce fertile soils. Laterite, a red soil which is a product of leaching, is commonly found in the tropics. It is composed mainly of iron and aluminium compounds,and poor in humus and essential plant nutrients, such as phosphorus, nitrogen and potassium. The black and brown soil of the temperate grasslands are the world's richest soils, with a high mineral and humus content. The light coloured desert soils tend to be very rich in minerals but have a low humus content. Mainly the soils ar...

What do women really want?

What men want is thought to be understood quite well. In general, their sexual desire is orderly, consistent, and narrowly directed. A heterosexual man is heterosexual. If you show him heterosexual sex, his sexual physiology and subjective, reported desire rise in tandem. Homosexual sex will leave him cold both physically and emotionally. For men, there is an excellent match between physiological arousal (as measured by penile tumescence) and level of reported desire. Viagra’s success demonstrates the simplicity of the male mechanism. Viagra does not target desire, but works by increasing genital blood flow, allowing erection. This, apparently, is all that is needed in many cases. As the penis rises, desire is already waiting. For women, the story is different. The female body, studies show , likes everything, or at least responds to everything (or does not know what it likes, some cynics will say). Female physiological arousal (as measured by vaginal lu...

What the Bible says about marriage and divorce

Matthew 5:31-32 “It has been said, ‘Anyone who divorces his wife must give her a certificate of divorce, but I tell you that anyone who divorces his wife, except for sexual immorality, makes her the victim of adultery, and anyone who marries a divorced woman commits adultery. Mark 10:2-12 Some Pharisees came and tested him by asking, “Is it lawful for a man to divorce his wife?” 3 “What did Moses command you?” he replied. 4 They said, “Moses permitted a man to write a certificate of divorce and send her away" “It was because your hearts were hard that Moses wrote you this law,” Jesus replied. 6 “But at the beginning of creation God ‘made them male and female. 7 ‘For this reason a man will leave his father and mother and be united to his wife, 8 and the two will become one flesh. So they are no longer two, but one flesh. 9 Therefore what God has joined together, let no one separate" When they were in the house again, the disciples asked Jesus about this. ...

Newsflashtalk.com Lifestyle, learning, health and food.

Search This Blog