Physics pt. 11: Digital and analog information

 Something analogue can be any value within a given range, and something digital can have multiple discrete and different levels, an analogue clock has hands which move around the centre and since it's analogue you can make it so that it displays certain numbers (10:30, 11:31, 5,03) and so on and it has infinite values.
A digital clock can do 10:30 and 10:30:51, which is more precise, but they have a finite number of values.

Sound is not only a wave, but it is an analogue, the amplitude which is the volume and the frequency which we hear as pitch, are all an infinite possible combinations.

The first recording of sound was imprinted on a material, like a vinyl record, or a music box, which is sound imprinted on a surface or material.

Physics pt. 10: Absorption and Reflection

Light can interact with many things, Absorption and Reflection.
If you were to be in the mountains and take a look at a clear pond, you would be able to see the surrounding mountains which are reflected off the water causing it to reflect the light.

And the same with snow, if you were to look straight at the snow, it would hurt your eyes, because it is very reflective and can blind you. That's when people are in he snow for a long time, they have to wear spectacles so they don't get blinded. And why some ski masks have tinting to help.

Alleles and genes

 Imagine the DNA being a sort of string (it's actually a sort of double helix, but imagine a string to make it easier).

Different parts of this string can be coded for different proteins, let's say that a certain part of this string is coded for DNA replication and another part for the pigmentation of your eyes. 

The most primitive life ever found was self-replicating RNA.

History pt 4: Agriculture

 The start of Agriculture started in, Iraq, Syria and Turkiye.

When people started farming, we started with the simple grains of wheat and barley.

Agriculture was founded by many different people, roughly around the same time. But there is no definite way of saying who figured out how to do agriculture, this wasn't taught by some travelling person teaching about the wonders of agriculture, but instead by individuals or groups of people who figured out how to water plants to grow food.

9000bce was commonly referred to as the start of agriculture, now let's go to what's modern-day Sudan, near the Sahara desert, grown in Sudan was Sorgum, but nowadays Sorgum is animal feed, and you can also make sweet syrup from it.

9000-7000bce was when we started domesticating animals, and 1000 years later when people started cultivating yam, okra (ladies finger), and black-eyed peas.

Starting around 6500bce, people around the Yangtze River, started growing rice, fully domesticated pigs buffalo, and chicken, and going north of the river at 5500bce people started cultivating millet and soybeans.

Then Mexico at 4000bce, started growing maize plants, beans, peppers, squashes and tomatoes.

5:50

 

Chemistry pt. 5: The Lewis diagram

The Luwis diagram is similar to the Bohr model as it is a simplified Bohr model, so let's take a Nitrogen atom, it has 5 valence electrons, 7 total elections but 5 valence. So to draw a Lewis diagram for a Nitrogen atom, you would just draw the Valence elections, without the rings,.

Now let's take a Nitride Ion, which is a nitride atom that gained 3 elections, so a nitride atom has 8 valence electrons,
if we were to draw a nitride ion with the 8 valences it would be an N with 8 dots around it,
and those dots being the Valence elections, now since it added 3 elections, it is now a negative 3 charge, and you would write an N with 8 dots around it, but because it is a negatively charged ion, it would have brackets with -3 outside it.

Introduction to heredity

 Heredity is inherited from traits from parents.

Some traits seem to dominate, like skin colour, hair colour, and height. 
The study of what gets passed on via genes was much, much older than the study of DNA.
The father of heredity study is Gregor Mendel who was actually a monk and he would experiment with plants and see which plant would follow which parent DNA more.

Certain traits are more prominent than others. An Allele and a Gene are very different and have defining characteristics for both, Gregor mentally was doing this in the 1850s.

Let's take two random chromosomes from the father, and mother, and on the chromosomes is a Locus, which is where the gene for the eye colour comes from, and let's say these are Homologous chromosomes, so they code for the same allele.
Now if both parents have different eye colours the person would be a heterozygote. Which is a heterozygous genotype. If both parents have the same eye colour of genes the person is a  homozygous, or this a homozygous genotype.

But Mendel discovered and learned something we will call dominance, this refers to one of the traits inherited from the mother or father is the more dominant gene. Now let's take two genes: One having blue eyes (the more dominant gene), and the other having brown eyes (the recessive gene).
And since brown eyes are the dominant gene, most of the people who have both genes will most commonly have brown eyes, which is named a Genotype.

Now a Phenotype, for example, let's say you have a brown eye allele from both parents. You will see that you will have brown eyes.

Apoptosis

The word Apoptosis comes from Greek: Apo meaning "Away" and Ptosis meaning "Falling".

Literally meaning "Falling Away", which is a type of cell death.
Apoptosis is one of the ways cells die.

One way is Necrosis, a type of death where the cell will swell and explode. This isn't an ideal cell death as when it "explodes" it can damage other cells around it and can cause cells from the immune system that cause inflammation as the immune system cells might believe that those parts from the cell that recently died from necrosis are invading the body and attacking it.
The human body tries its best to avoid necrosis as it usually happens when the body is exposed to a chemical toxin and it causes the cell to die unnaturally.

The other way is Apoptosis which is the less extreme way of cells dying, for example when your hands are forming in your mother's womb, your hand starts out in a sort of paddle, and Apoptosis widdles it down to form your fingers.
Apoptosis is kinda like dissolving the cells.

Another place where Apoptosis shows up is in a tadpole, when a tadpole turns into a frog, the cells use Apoptosis to remove the tail. 

Apoptosis is happening all the time in your body. It is meant to keep the cells from multiplying too much, while not damaging the cells around it. As too many cells can cause cancer.

Also when cells suffer from DNA damage, if they can't fix it by themselves, they undergo Apoptosis. So with Apoptosis, it can save you from cancer. 

Keep in mind that not all cells will die to Apoptosis. Some will die to Necrosis