Answer:
The first and best defense against plant diseases is a healthy plant, which is the main task of an accomplished gardener. Preventing and managing plant disease begins even before planting, with site preparation and plant selection.
When a plant does not look normal, or as expected, a gardener may assume that the plant is diseased and control measures are needed. To properly diagnose plant problems, the gardener needs to have background knowledge about the plant, the current environment, and the typical diseases or other problems to which the plant is susceptible. Such information can help prevent an inaccurate diagnosis that may lead to unnecessary pesticide use, wasted time and expense, and continued plant decline.
This publication provides gardeners with information on how to establish and maintain healthy plants, and describes a systematic approach to identifying and solving problems that do occur.
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Explanation:
Answer:
From fertilization and to the end of the second week.
Explanation:
The development of the fetus is divided into three periods, established by most embryologists: pre-embyonic period, which goes from fertilization to the second week of development, embryonic period, which goes from the third week to the eighth week, and the fetal period, which goes from from the third month until the end of pregnancy.
The pre-embyonic stage begins at fertilization and remains until gastrulation. By the end of the second week the embryo already has the neural tube formed, although it is still open at both ends.
The correct answer would be C
