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<em>Ossification is a process in which the mesenchymal cells and cartilages convert to bone during development. it is has two types: Membranous and endochondral ossifications. It occurs in mesenchyme which has formed a membranous sheath (figure 4) .</em>
GnRH is secreted by the hypothalamus.
FSH and LH are secreted by the anterior pituitary gland in response to the GnRH that was secreted by the hypothalamus.
<span>The most obvious change due to seasonal variation is the change from summer to winter. Some animals migrate to other parts of the world, such as migratory birds. Many animals in colder climates hibernate. In both cases, the absence of these animals leads to a gap in the ecosystem. In regions with highly seasonal rainfall, the low rainfall season can lead to low flows in rivers, and a reduction of certain habitats for some aquatic organisms, such as beaver or aquatic insects.</span>
Answer:
hydropower is the best source
