We are reading All the Light We Cannot See, a novel written by Anthony Doer, this book is written in two difference perspectives and different times in the lives of these characters. Sometimes you are with a blind French girl and sometime you are in the story with a German orphan. And although these characters’ countries are not allies and they are very different you can still see that everyone goes through very rough times, and has to make rough decisions and sacrifices.
Personally I found this book a little hard to read at times, so while I read I have to make sure I know exactly when the events are happening, because most of the story is written as a flashback. But sometimes it will go to “current time” and sometimes it will be in a random persons view. But other than that I think this novel has a very good story and its a creative and smart way to write the novel.
What is a neuron?
A neuron is a basic unit of the brain, it is a specialized cell designed to pass on information to other nerve cells, muscle cells, or gland cells. Most neurons have a cell body, an axon, dendrites and a Merlyn Sheath. Axons transfer and carry signals to other neurons and the dendrites receive these signals. And the cell body is the neuron’s life source. Some neurons also have a myelin sheath, the myelin sheath is a fatty substance which surrounds parts of the axon, forming an electrically insulating layer. The only neuron that has a myelin sheath is the sensory neuron and they main purpose is to improve the speed of the neural impulse along the axon.
What is action potential?
An action potential is the sending of electrical impulses which is how neurons communicate. This happens trough depolarization and repolarization. At resting potential, the axon is negatively charged inside at -70mV. And when depolarization happens parts of the axon open up to let in two sodium ions which changes the charge inside the axon to positive. But then repolarization happens and potassium ions leave the axon which makes it negative again. The process of depolarization and repolarization happens all through the axon which causes the charge to move down the neuron.
So, the purpose of the action potential is to move the charge down the neuron so now that we the action potential at the axon terminal is moves to the the receptor of the next neuron. Also, the Synapse has three parts: the synaptic gap, the presynaptic membrane, and postsynaptic membrane. So, when it reaches the axon terminal it links to the presynaptic membrane and that then releases pockets of chemicals which are called neurotransmitters. These are released into the synaptic gap. And the neurotransmitters then connect or bind onto the receptors of the second neuron which is connected to the dendrites. Once they are binded they trigger either an excitatory or inhibitory respond. This will determine if the receiving neuron will continue to send the action potential (excitatory) or stop sending the message (inhibitory).
How an action potential moves along the neuron fiber
It goes through the axon
Neuron Structure and job.
Dendrites– Conducts messages toward cell body
-receive information from other neurons and sensory receptors
Axon– Conducts message away from cell body
Cell body– The cells life support center
Myelin Sheath- Covers the axon of some neurons and helps speed neural impulses
Terminal branches of axon- Form junction
A nerve impulse is an electrochemical reaction called action potential
1.I had some trouble with finding the vertex
2. y = 3x2 + x – 2
3. To find the vertex, I look at the coefficients a, b, and c. The formula for the vertex gives me:
h = –b/2a = –(1)/2(3) = –1/6
Then I can find k by evaluating y at h = –1/6:
k = 3( –1/6 )2 + ( –1/6 ) – 2
= 3/36 – 1/6 – 2
= 1/12 – 2/12 – 24/12
So now I know that the vertex is at ( –1/6 , –25/12 ).
At first i didn’t really know what the vertex was and now i know the its the highest or lowest point of the graph and this helps when I’m also trying to find the Domain and Range. (also learned Vertex form was really helpful)
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?
Darwin theory was that species will have changes in both physical and behavioural as time passes to make the organism more fit for its environment. Also the discovery of DNA proved his theory, by examining DNA it shows we all have a common ancestor. DNA also shows that when we are born we get some of our moms and some of our dads genes passed on to us, and sometimes there are mutations and often in animals the mutation is good or else the organism wont survive. By looking at DNA we can see certain mutations and places where DNA is different in species that were once the same. Darwin went to the Galapagos Islands and saw that the same species of finches looked different and though since they were on different Islands and they ate different things their beaks had to change in order for them to be able to eat. And those that didn’t change they would no longer be fit for the environment, they would die because they cant eat and their genes would not get passed on, this is called survival of the fittest.