My girls are 7 months old today and very different. Rain is intense in her attention to things and small details, she is quiet and is always off exploring (even though she only scoots and rolls). Sometimes she squeaks when she is excited, she doesn't like sweet food as much as veggies. Her favorites are peas and plain cereal. Rain was the first to escape from the car seat when she's not strapped in and the first to figure out how to hold her own bottle. She's always examining objects and even her own hands just to see how they work. Today I watched her examine a Lego block for a good twenty minutes, just rolling it around putting her hand and fingers in all the holes.
River is more vocal and always wants to be the center of attention, where Rain examines new things River shakes them and tries to get them to make noise. She was the first to vocalize and giggle, her belly is ticklish too. River also growls at people and things, not an angry growl but just a very guttural sound, it's very comical, like a tiny dinosaur trying to be heard. She loves juice and the sweet fruity foods, when she doesn't want to eat something she blows raspberries to get it out of her mouth. Today while I was feeding her and Rain mixed veggies she blew most of it out and I got more on me then she ate. River is goofy, personable and loves to cuddle.
It's crazy to see how different they are. Rain is the little scientist trying to figure out how the world works and River is the social butterfly trying to mimic the big people.
Friday, August 2, 2013
Algebra 08.02.13
The last part of lesson two focuses on exponents. When a dealing with several variables multiplied together that have exponents the exponents can be added together to simplify the expression. For example if I have x^2*y^4*x^9*3 (where ^ is used to show there is an exponent) I can simplify to x^11*y^4*3.
Lesson three is about polynomials. The distributive property allows us to take the expression a(b+c) and simplify it to ab+ac. For example say we have the expression 5-(6-x) we can think of the negative sign as a -1 and distribute it to get 5-6+x or -1+x. When multiplying polynomials together make sure to multiply every term in the first polynomial by every term in the second polynomial. For example (x+2)(x+5)= x^2+5x+2x+10 which simplified is x^2+7x+10.
Lesson three is about polynomials. The distributive property allows us to take the expression a(b+c) and simplify it to ab+ac. For example say we have the expression 5-(6-x) we can think of the negative sign as a -1 and distribute it to get 5-6+x or -1+x. When multiplying polynomials together make sure to multiply every term in the first polynomial by every term in the second polynomial. For example (x+2)(x+5)= x^2+5x+2x+10 which simplified is x^2+7x+10.
Thursday, August 1, 2013
Algebra 08.01.13
Lesson 2 in Udacity's College Algebra course is about expressions. It starts by going back over the commutative property of both addition and multiplication. As a reminder the commutative property just means that the order of terms or factors doesn't matter. So a+b+c is the same thing as b+a+c and a*b*c is the same as c*a*b and so on. When combining like terms it is important to remember that they need to have the same variable and power (x cannot be added to x squared). So 2x+3x+4-2y can be simplified to 5x-2y+4 but no further.
A polynomial is an expression with constants and/or variables that are combined using addition, subtraction and multiplication, where all exponents are non-negative integers. The degree of a term is the sum of exponents on the variables in that term. So x squared times y cubed would have a degree of 5 because the exponents 2 and 3 add up to 5. The degree of a polynomial is equal to the highest degree of any of its terms. the standard form of a polynomial is to put the terms in order from highest degree to lowest degree.
A polynomial is an expression with constants and/or variables that are combined using addition, subtraction and multiplication, where all exponents are non-negative integers. The degree of a term is the sum of exponents on the variables in that term. So x squared times y cubed would have a degree of 5 because the exponents 2 and 3 add up to 5. The degree of a polynomial is equal to the highest degree of any of its terms. the standard form of a polynomial is to put the terms in order from highest degree to lowest degree.
Psychology 08.01.13
So over the last few days I have been working on Lesson 3 "The Biology of Behavior". Last post I talked about colorblindness which is a trait controlled by one gene. There are, however, many traits that are controlled by multiple genes such as eye color or height, these are called polygenic traits. Traits are not just affected by genes but also by the environment. Identical twins can posses very different traits because of their life choices, if one overeats and smokes while the other doesn't they are going to look very different. Epigenetics is the study of how our environment can turn different traits on and off. There is a study about two genetically identical mice whose mothers were fed different diets while pregnant, one high in methyl groups and one without. The end result was that one mouse came out obese and yellow while the other was normal and brown. These mice have the same genotype but different phenotypes. The same principals hold true for personality traits, there is a gene that is referred to as the warrior gene, this gene was thought to cause aggressive behavior but as it turns out many people have the gene without displaying aggressive behavior. In fact it takes an abusive childhood coupled with the Monoamine Oxidase A (warrior gene) to cause the more aggressive personality, making this an excellent example of how the environment can affect the gene expression.
The next part of Lesson 3 had to do with the nervous system. The nervous system can be broken down as into the Central and Peripheral nervous systems. The central nervous system consists of the brain and spinal cord while the peripheral accounts for all the other nerves. The peripheral system can be broken into the somatic and autonomic systems, the autonomic system controls functions like heart beat, breathing, digestion etc... the somatic is responsible for voluntary functions. Both of these systems have motor and sensory nerves. The autonomic nervous system has both a sympathetic and parasympathetic nervous system. The sympathetic nervous system is responsible for the fight or flight response, when activated it does things like dilate the pupils, increase heart rate, inhibit digestion and relax the bronchi to make taking in more oxygen possible. When the parasympathetic nervous system is activated it has the opposite effect, the pupils and bronchi are restricted, heart rate is slowed and digestion is stimulated.
There are two types of cells that make up the nervous system, Glial cells and Neurons. Glial cells provide structural support and remove debris while Neurons process and transmit information. There are three different types of neurons; sensory, motor and interneurons, the interneurons connect neurons to one another. Below is a very rough drawing of a neuron. The Soma is the center of the cell and contains the nucleus. Branching off of the soma are the Dendrites, dendrites connect to other neurons and are the receivers for the cell. The axon transmits the electrical charge (when a neuron fires) to the terminal buttons, the mylin sheath (not present on all neurons) helps to speed up this process. The terminal buttons release neurotransmitters to neighboring neurons and the process repeats. Neurotransmitters can be either inhibitory or excitatory, excitatory neurotransmitters increase the chance that a neuron will fire while inhibitory ones decrease that chance. So to put it all together lets say an excitatory neurotransmitter is received by the dendrites of a neuron, if enough are received the neuron will fire off an electrical signal that runs down the axon and tells the terminal buttons to release more neurotransmitters once they do the cycle repeats with the next neuron.
The next part of Lesson 3 had to do with the nervous system. The nervous system can be broken down as into the Central and Peripheral nervous systems. The central nervous system consists of the brain and spinal cord while the peripheral accounts for all the other nerves. The peripheral system can be broken into the somatic and autonomic systems, the autonomic system controls functions like heart beat, breathing, digestion etc... the somatic is responsible for voluntary functions. Both of these systems have motor and sensory nerves. The autonomic nervous system has both a sympathetic and parasympathetic nervous system. The sympathetic nervous system is responsible for the fight or flight response, when activated it does things like dilate the pupils, increase heart rate, inhibit digestion and relax the bronchi to make taking in more oxygen possible. When the parasympathetic nervous system is activated it has the opposite effect, the pupils and bronchi are restricted, heart rate is slowed and digestion is stimulated.
There are two types of cells that make up the nervous system, Glial cells and Neurons. Glial cells provide structural support and remove debris while Neurons process and transmit information. There are three different types of neurons; sensory, motor and interneurons, the interneurons connect neurons to one another. Below is a very rough drawing of a neuron. The Soma is the center of the cell and contains the nucleus. Branching off of the soma are the Dendrites, dendrites connect to other neurons and are the receivers for the cell. The axon transmits the electrical charge (when a neuron fires) to the terminal buttons, the mylin sheath (not present on all neurons) helps to speed up this process. The terminal buttons release neurotransmitters to neighboring neurons and the process repeats. Neurotransmitters can be either inhibitory or excitatory, excitatory neurotransmitters increase the chance that a neuron will fire while inhibitory ones decrease that chance. So to put it all together lets say an excitatory neurotransmitter is received by the dendrites of a neuron, if enough are received the neuron will fire off an electrical signal that runs down the axon and tells the terminal buttons to release more neurotransmitters once they do the cycle repeats with the next neuron.
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| Neuron |
Sunday, July 28, 2013
Algebra 07.28.13
Yesterday I finished up the Introductory Algebra Review on Udacity ( I know the certificate says 07.25.13 but that was for getting 80% of the questions right, I finished out the last unit and test on the 27th), I'm starting the College Algebra course today. Lesson one is about numbers, numbers are a construct in that they do not exist in the real world, we use the concept of numbers to do everything from balancing our checkbooks to launching satellites into orbit. Natural numbers are the numbers 1 to infinity, increasing by 1 at each step so 1, 34 and 375 are natural numbers but -3, 3.6, and 0 are not. Whole numbers are all natural numbers and the number 0. Integers are all whole numbers and negative numbers that are not fractions or decimals so they range from -infinity to +infinity. These are all sets of numbers, of course a set can be made up of any combination of numbers. Another way to express the relationship of of one set of numbers to another is to say x is a sub-set of y, for example whole numbers are a subset of integers because all whole numbers are integers. Rational numbers are any number that can be written as a/b where a and b are integers and b is not 0. Irrational numbers cannot be written as ratios of integers, so any square root that is not a perfect square is an irrational number, pi is also an irrational number.
There is also a review of variables, constants, expressions and equations. I am not going to go back over them because that information is in my previous algebra posts.
There is also a review of variables, constants, expressions and equations. I am not going to go back over them because that information is in my previous algebra posts.
Psychology 07.28.13
Today in the Intro to Psychology class I went over good practices in experiments, specifically in reference to psychological experiments. Randomly assigning participants to either the experimental or control group can help insure that both groups are similar. Not telling participants which group they are in eliminates bias on their part, having both the participants and the experimenter in the dark is called a double blind study and this eliminates bias on both parts. An important thing to note about psychology is that a review board has to okay any experiments, the benefits must outweigh the risks and participants must sign informed consent. Participants must also be able to leave the study at anytime without negative consequences.
Lesson 3 starts out with an introduction into how long modern humans have been around as compared to other humans. Modern humans have existed for the last 200,000 years, before that were Neanderthals, homo-erectus and homo-habilus. Homo habilus, the first humans, lived from about 2.4 to 1.4 million years ago. Our closest relative would be the Neanderthals and we actually interbred with them before they died off around 28,000 years ago so many of us have Neanderthal DNA. Our closest living relative is the chimp, with whom we share about 98% of our DNA, the other 2% is what makes us uniquely human. These changes happened over a long period of time due to mutations and natural selection, in other words, we evolved.
The changes to our brains is probably what makes us most human. Our brains are bigger than our ancestors and the most differences between our brains and theirs is in the frontal lobe. Having a bigger brain did not come without consequences, childbirth is more painful because of larger skulls and we need more food to fuel our brains.
There is a section on DNA structure, from the nucleotides Thymine, Adenine, Guanine, Cytosine to the 23 chromosomes that make up our DNA. Also it is not the amount of DNA but the sequence that makes us more complex, in fact some amoeba's have more DNA than than anything else on earth. Only about 2% of our genome actually codes for proteins (these portions are called genes), most of the rest regulates which genes are activated, but some of this remaining 98% we're not really sure as to what its purpose is. Alleles are versions of genes, for example my dad has the allele for colorblindness where as my mom does not, so being that this allele only exists on the x chromosome (of which I have 2) I have one allele for colorblindness and one for normal vision. Luckily for me the colorblindness allele is recessive which means that I would need two in order to be colorblind. However this also means that there is a 50/50 chance my daughters will also carry the colorblindness allele and 50/50 chance that any sons I would have would be colorblind. Why? Because males have an x and a y chromosome so they only get one chance at a good allele, where as the x chromosome from my mom allows me to recognize all the colors males don't have a second x chromosome to cancel out or hide the colorblindness allele. This is why more men than women are colorblind, for a woman to be color blind her father would have to be colorblind and her mother would have to carry the colorblind allele.
Lesson 3 starts out with an introduction into how long modern humans have been around as compared to other humans. Modern humans have existed for the last 200,000 years, before that were Neanderthals, homo-erectus and homo-habilus. Homo habilus, the first humans, lived from about 2.4 to 1.4 million years ago. Our closest relative would be the Neanderthals and we actually interbred with them before they died off around 28,000 years ago so many of us have Neanderthal DNA. Our closest living relative is the chimp, with whom we share about 98% of our DNA, the other 2% is what makes us uniquely human. These changes happened over a long period of time due to mutations and natural selection, in other words, we evolved.
The changes to our brains is probably what makes us most human. Our brains are bigger than our ancestors and the most differences between our brains and theirs is in the frontal lobe. Having a bigger brain did not come without consequences, childbirth is more painful because of larger skulls and we need more food to fuel our brains.
There is a section on DNA structure, from the nucleotides Thymine, Adenine, Guanine, Cytosine to the 23 chromosomes that make up our DNA. Also it is not the amount of DNA but the sequence that makes us more complex, in fact some amoeba's have more DNA than than anything else on earth. Only about 2% of our genome actually codes for proteins (these portions are called genes), most of the rest regulates which genes are activated, but some of this remaining 98% we're not really sure as to what its purpose is. Alleles are versions of genes, for example my dad has the allele for colorblindness where as my mom does not, so being that this allele only exists on the x chromosome (of which I have 2) I have one allele for colorblindness and one for normal vision. Luckily for me the colorblindness allele is recessive which means that I would need two in order to be colorblind. However this also means that there is a 50/50 chance my daughters will also carry the colorblindness allele and 50/50 chance that any sons I would have would be colorblind. Why? Because males have an x and a y chromosome so they only get one chance at a good allele, where as the x chromosome from my mom allows me to recognize all the colors males don't have a second x chromosome to cancel out or hide the colorblindness allele. This is why more men than women are colorblind, for a woman to be color blind her father would have to be colorblind and her mother would have to carry the colorblind allele.
Saturday, July 27, 2013
Algebra 07.27.13
Yesterday we learned a bit about slope and how horizontal lines will always have a slope of zero because if you divide zero by any number it is still zero. This brings us to vertical lines, these lines have a change in x of zero, because we can't divide by zero the slope of any vertical line is undefined. Given two points (x1,
y1) (x2,y2) we can then find the slope using this equation where "m" stands for slope, m=(y1-y2)/(x1-x2). So how do we find the graph or visual representation of a line from this information? We use the slope of a line and a point on the line, we can also represent a line using slope-intercept form. This uses the slope and the y intercept to represent a line or y=mx+b where again m is slope and b is the value of y at the y intercept. We can also use point-slope form y-y1=m(x-x1) where (x1, y1) is any point on the line. If we solve for y we can convert point-slope form to slope-intercept form.
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