The nerve cells in our body take on 3 different forms: sensory, motor and inter-neurons
The function of a neuron is to carry electrical messages around your body. They are composed of the cell body, the dendrites, and the axon. The dendrites are what conduct messages towards the cell body, the axon does the opposite, and conducts messages away from the cell towards the next cell. Motor neurons have short dendrites and long axons, where as sensory neurons and inter-neurons have longer dendrites and shorter axons.
Action potential is a process that occurs in the neuron. A neuron has negative potassium ions outside the membrane and positive sodium ions inside. The action potential travels down the axon and while this is happening, there is a change in the membrane in polarity. This happens by the axon moving the sodium ions outside the cell and the potassium ions inside the cell.
The action potential reaches the axon terminal (the synapse) and causes the release of neurotransmitters into the synaptic gap. There are two membranes in the synapse, the pre-synaptic membrane of the axon and the post synaptic membrane of the dendrite. The space between these two membranes causes the synaptic gap. When the receptor receives the neurotransmitter, the neurotransmitter can either be received as excitatory or inhibitory. When receiving a neuron, Excitatory stimulates Action potential, whereas as inhibitory represses the action potential. If the excitatory charge is greater than the inhibitory charge, action potential is produced.
How did the discovery of DNA prove that Darwin’s theory of evolution was correct and how does it change the way we view evolution today and into the future?
The theory that Darwin stated was an absurd one that everyone was skeptical about, at first. All of the living things on Earth shared a common ancestor, a prehistoric animal, the fish. Fish then evolved into all the creatures we have today. They did this through adaptation and mutation, new species blossomed as they evolved to survive the environments they were put in. Therefore, all species are related to each other because we share that common ancestor.
Once DNA was discovered, it proved that Darwin’s crazy theory, wasn’t so crazy. Darwin stated that we humans evolved from apes, and when the DNA was studied, an almost-perfect match was found between human DNA and ape DNA. We are in fact, very similar, genetically, to apes, so we must have had some state of our evolution through them. Furthermore, he was also correct about how all species were evolved from fish. When scientists discovered the Tiktaalik, a prehistoric fish, the species showed it was an underwater fish with four-legs. Therefore, we can conclude that the Tiktaalik was the transitional phase between other species and fish, and that it further explains how fish were able to get up on land, and evolve into what we are today.
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CHALLENGE: Make a boat that can float in water and hold the most amount of pennies.
PROBLEM: What materials can we use and how can we make a boat that will float in water?
HYPOTHESIS: If we use tinfoil as a base, and attach the straws on the perimeter and marshmallows on the corners of the bottom, the boat should be able to float.
IDEA FOR ORIGINAL DESIGN: Insert image and write a description explaining your thinking/reasoning as to why you chose that particular design
We thought that the straws would add some support to the base, and the marshmallows would be able to resist water and therefore assist the boat in staying above the water once weight (pennies) were added. We also decided to add wax paper in the middle to hold a sort of curve for the pennies.
HOW MANY PENNIES DID YOUR BOAT HOLD?
35
WHAT WOULD YOU KEEP OR CHANGE ON YOUR BOAT DESIGN IF YOU WERE TO DO THIS AGAIN? (saying nothing is not an option)
For the most part, our theory worked. The straws added support to the base and but it also allowed some water to seep through, next time, we should make sure that the ends of the straws are secure so they become more water resistant. The marshmallows also really helped the boat stay afloat and so did the wax paper, however it could only hold 35 pennies.
There are many reservoirs that supply us with water, and that are being refilled naturally by our water cycle. Whenever it snows or rains, the water is collected in the reservoirs. When we need to use it, the water goes through huge pipes called penstocks, and push the water through turbines. The water causes the turbines to spin and generators create clean electricity. Generators usually generate electricity with a low voltage so that it can travel long distances all around BC. The voltage is increased with a step-up transformer so not to waste any energy.
Pros/Cons of Hydro-Electric Power
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How Thermal Power Plants Produce Electricity
Oil, natural gas, or coal are burned to produce steam (not from the coal, but from the water that the coal is heating). The steam is under great pressure and is transmitted through large pipes. The pressure pushes the blades of the turbines and causes them to spin. The turbine is attached to a generator that produces electricity.
Pros/Cons of Power Plants
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How Electricity is Transmitted from the source to homes
The power is transported through grids across BC, over mountains and large areas. The grids are the things that we call “power lines.” The voltage is then reduced with a transformer from a high voltage, to a voltage that’s more common for household use.
A Summary of How the Transmission Process Works
In conclusion, electricity is an important part of our everyday lives. There are many different ways that we can produce it, and each method has pros and cons to it. Electricity is created, and then it’s voltage is increased with a step-up transformer. It is distributed across the country using power lines, or grids. Once it gets to our street, it’s voltage is decreased with a step-down transmitter so that it’s useable for our homes, and so we are not wasting energy.
