Rabu, 09 Januari 2013

Growth and Development


1. Growth is the increase in size of living things because there is a process called the cell division and enlargement. Growth was also measured and can also be expressed quantitatively:
2. The development is the process by which living things are heading into adulthood. That development was not only able to be measured or expressed in numbers, but can also be expressed through the development of a future change in the shape and level of maturity.

1. Growth and development in plants
Growth and development in plant life can occur because of a mitotic division at the growing point, followed by enlargement or cell elongation. Growth and development can also be divided into two, namely the growth of primary and secondary growth. If the primary growth is the result of an activity that occurs in the primary meristem tissue cells, whereas secondary growth is the result of a secondary meristem tissue activity. Pace of growth in plants can be measured by a tool called auksanometer. And the following is the factors that can affect growth and development in plants.
a. Genes are a factor of the nature of heredity in plants. The gene was located in the chromosomes in the nucleus of cells contained in plants.
b. The hormone is a substance that is needed once in a process that will be carried out in the plant body. And the following are some hormones that can affect the rate of growth in plants as follows.

1) Auxin, which is located yaitui hormones in the body to function at all plants and in promoting stem elongation, root growth, fruit growth, phototropism, and geotropisme.
2} Gibberellins function was to stimulate germination in seeds and buds, stem elongation, leaf growth, flowers, and fruit, and can also affect the growth and differentiation in the roots.
3) Cytokines function is to influence the growth and differentiation in the roots of plants, and can also stimulate cell division and growth, germination and flowering, and can also inhibit the aging process in plants.
4) This hormone abscisic acid plays an important role in the inhibition of the growth, stomata closed during water shortages, and may delay the growth (dormancy) in plants.
5) ethylene gas which was instrumental in spurring the process of fruit ripening and trunk becomes thicker.
6) Kaulokalin which serves to stimulate the process of formation in the stems of plants.
7) Rhizokalin function once to stimulate the formation of the root.
8) Filokalin which serves to stimulate the formation of the leaf.
9) Antokalin which serves to stimulate a process of formation of the flower.

c. Light, especially light is the sun, which is desirable in the process of making food in tumbuham or known as photosynthesis.
d. Temperature. Temperatures required by plants so plants can grow and develop properly called the optimum temperature. While the lowest temperature when the plant is still growing and developing well, it is called with the name of minimum temperature, and that the highest temperature is called the maximum temperature.
e. Water is very important for plants because it can be used for growth in a process called photosynthesis, and keep the humidity at tumbuha, and can help the terjdi seed germination in plants

2. Growth and development in animals
Growth and development in animals occur in all parts of the body. Growth in animals is the result of an activity in mitotic cell division. Well speaking of mitosi, mitosis is what ya ..?
Mitosis is division in the animal's body, except the sex cells. And these factors that affect growth and development in animals that genes, hormones, water, temperature, activity, food, and sunlight.

Metamoforsis
Metamorphosis is the change in the shape and structure of the body in animals, from embryo to adult stage Phase metamorphosis is divided into 2 types, namely:

Complete metamorphosis is a stage in the animal's body shape changes in a clear and distinguishable, from egg, larva or caterpillar, to adult animals. Complete metamorphosis occurs in the butterfly

Metagenesis are descendants of rotation between the vegetative phase (producing spores) and the generative phase (occurring due to fusion of sex cells between spermatozoid (male sex cell) and egg / ot / um (female sex cell)). Metagenesis generally found in plants, moss and fern.

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