Answer:
The Miller and Urey experiment is a well-known classic experiment in which hypothetical conditions of the early Earth's evolution were simulated to test the possibility of chemical evolution. In fact, this was an experimental test of the hypothesis previously expressed by Alexander Oparin and John Haldane that the conditions that existed on primitive Earth promoted chemical reactions that could lead to the synthesis of organic molecules from inorganic ones. It was held in 1953 by Stanley Miller and Harold Urey. The apparatus designed for the experiment included a mixture of gases corresponding to the notion of the composition of the atmosphere of the early Earth in the 1950s, and electric discharges passing through it (simulating lightning strikes on the ground). The Miller and Urey experiment is considered one of the most important experiments in the study of the origin of life on Earth.
Answer:
<u>acetylcholine</u>
Explanation:
In the pre-synaptic knob there are vesicles which contain a transmitter substance called acetylcholine. When an impulse reaches the synaptic knob, it stimulates the vesicles to move towards the pre-synaptic membrane releasing the acetylcholine.
The transmitter substance makes the membrane permeable. The neuromuscular junction contains the sensory neurone(afferent), motor neurones(efferent) and the relay neurones(connector).
Answer:
Answer for question 2:
It is important to receive data from three separate locations because the more we know about the seismic waves and the places that they are more we gain for learning about them.
Explanation:
<span>A low white blood cell count usually is caused by: Viral infections that temporarily disrupt the work of bone marrow. Certain disorders present at birth (congenital) that involve diminished bone marrow function. Cancer (or other diseases that damage bone marrow)</span>
Sponges have medicinal properties due to the presence of microbial chemicals that may control viruses, bacteria, tumors and fungi. They even look rather nice, and some species are helpful to humans when dried and put to use in the kitchen and bathtub.Up to 99% of the world's animal species are invertebrates.