Answer:
During a chemical change, the composition of matter always changes. Four possible clues to chemical change include a transfer of energy, a change in color, the production of a gas, or the formation of a precipitate.
Explanation:
<span>Aplysia is a marine gastropod mollusc which is an often used model organism in neuroscience, especially on the cellular biology of learning and memory. What makes them easy to work with are their giant neurons, which are one of the largest. Aplysia neurons are suitable for studies of how neurons and neural circuits control behaviours. Its defensive reflex has been studied because it is mediated by electrical synapses, which allow several neurons to fire synchronously.</span>
Answer: C & A
Explanation:
The HOX genes encodes important transcription factors. This factors causes protein to be made that specify cell fate and identify; embryonic primary axis, secondary axis and plays important roles in various tracts development.
Answer: Natural selection can be defined as the differential survival and reproduction of members of the population of a species that have suitable traits to survive in a population of species.
Explanation:
The punctuated changes in the population of species have been found inordinately faster in the geological time scale, but changes per-generation have been relatively slow. Also, the rate of evolution in such a population is also slow. The punctuated changes in the population are because of evolution but the per-generation changes are the outcomes of the natural selection, in which only the beneficial traits are passed from one generation to another.
Answer:
The correct answer is option a.
Explanation:
Osteoporosis refers to a condition that weakens the bone, and enhances the threat of unanticipated and sudden fractures, also known as porous bones. It leads to an enhanced loss of bone mass and strength. The disease often advances without any kind of pain or signs.
There is a direct association between the reduction of estrogen post menopause and the emergence of osteoporosis. Postmenopause, the breakdown or resorption of bone takes over the formation of novel bone. Estrogen diminishes the function and number of osteoclasts. Thus, the reduction in the levels of estrogen after menopause leads to bone loss.