Answer:
Oxytocin
Explanation:
The release of oxytocin is signaled by the fetal brain about 38 weeks after conception. Oxytocin is also called birth hormone as it stimulates uterine contraction.
The uterine contractions stimulate the release of more oxytocin through a positive feedback loop. Oxytocin stimulates contraction of the smooth muscles in the wall of the uterus which in turn finally leads to childbirth.
It was commonly understood in the past the dogs come from a lineage of wolves, but that isn't the case now. Scientists have found out that dogs and wolves come from a common ancestor about 9,000 to 36,000 years ago. This was done through extensive DNA analysis with samples that took into consideration the geographic locations of their origin and of modern isolation. This yielded a result that despite geographical difference, the dogs are more closely related than to wolves. It is now understood that the complication of the genetic relationship between the two was caused mainly by interbreeding during the course of time, but it isn't just that. Some other factors have come into play including the presence of humans.
Backward chaining starts with a goal then searches back. Forward chaining starts with facts and searches forward.
Answer:
The efficiency of the hair dryer is 0.2 or 20%
Explanation:
The efficiency of a machine or any appliance is a measure of the useful work done by the machine when an effort is applied to the machine. The higher the efficiency of a machine, the more useful work the machine does.
Due to the economical and environmental impact of energy production, machines and appliances of high efficiency are being developed and recommended for domestic as well as industrial use nowadays.
In electrical appliances, energy is usually supplied by electrical power units. The higher the efficiency of an electrical appliance, the less power it consumes to do useful work. For a hair dryer which takes in 3000 J of energy per second and transfers 600 J of useful heat energy, its efficiency is calculated with formula below:
efficiency = useful energy / total energy input
Efficiency = 600 J / 3000 J = 0.2
Therefore, the efficiency of the hair dryer is 0.2 or 20%
Answer:
The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat.
