AP Bio: Genome Chromosome 2: Species

The evolution of man.

In "Species," the second chapter of Genome, Matt Ridley discusses how the species of humans came about.  Chromosome 2 is actually the second biggest human chromosome and is formed by two medium-sized ape chromosomes fusing together.  Ridley mentions that it is surprising that humans don't have twenty0four pairs of chromosomes because chimpanzees and other monkeys have twenty-four pairs and according to the theory of evolution, we are closely related to them.  He goes on to say that although "the human species has shown a remarkable capacity for colonising different habitats" (25), "the remarkable truth is that we come from a long line of failures."  Humans were once apes that almost became extinct fifteen million years ago when we were in competition with better-adapted monkeys.  He mentions that we are descended from synapsid tetrapods, limbed fishes, and chordates, then goes on to describe our journey to existence through natural selection and evolution.  Ridley ends with concluding that it is crazy that small differences in the genes of different species result in large differences in behavior and that  "genes are recipes for both anatomy and behaviour" (37).


Source: 
Genome: The Autobiography of a Species in 23 Chapters by Matt Ridley
picture from: http://www.dailymail.co.uk/sciencetech/article-1070671/Evolution-stops-Future-Man-look-says-scientist.html

AP Bio: Genome Chromosome 1: Life

In "Life," the first chapter of Genome: The Autobiography of a Species in 23 Chapters by Matt Ridley, the author describes life as "a slippery thing to define, but it consists of two very different skills: the ability to replicate, and the ability to create order" (12).  He talks about how information is the key to these two conditions of life, and that DNA is that information, "written in a code of chemicals" (13).  He also talks about how life began: Chromosome I, the largest chromosome, is called the "ur-gene" (18) and was a "combined replicater-catalyst" which may have caused the chemicals around it to replicate itself.  He compares about the genes being a language of itself in a book.




Source:
Genome: The Autobiography of a Species in 23 Chapters by Matt Ridley
picture of Genome book from: http://vanlagerstatten.blogspot.com/

AP Bio: Double Fertilization

Double fertilization is the unusual reproductive process that flowering plants go through and there are two fertilization events, not one.  The ovule (female reproductive part of plant) has a megaspore (mother) that is diplod (2n) but undergo meiosis to produce four haploid cells (n).  Three of these degenerate and one megaspore is left.  This remaining megaspore undergo mitosis to produce eight haploid nuclei, making a multinucleate structure called an embryo sac.  Three antipodal cells form at the opposite side of the microphyle opening.  Two synergids and the egg form near the microphyle opening and two polar nuclei remain together as a central cell.  Before fertilizing, a pollen grain lands on the stigma and germinates to send a pollen tube down the style and the ovary.  A haploid/generative cell travels down the tube and divides to produce two haploid sperm cells.  The pollen tube digests through one of the synergids, the synergid degenerates, and one of the sperm cells fertilizes the egg.  The second sperm fuses with both polar nuclei to make a triploid (3n) cell that later becomes the endosperm, the embryo's food supply.


Source:
information from: http://bcs.whfreeman.com/thelifewire/content/chp39/3902001.html
picture from: http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookflowersii.html

Anatomy and Physiology: Control Systems

The human body has two control systems: the nervous system and the endocrine system.  The nervous system is faster and more complicated.  It sends electrochemical signals which stimulate immediate responses.  When electrochemical signals is being transferred, it goes down the axon of a nerve cell and is transmitted across the synapse (gap between nerve cells) to the next neuron.

The endocrine system works more slowly.  Hormones are released into the bloodstream, which then transports them to their target cells.  The hormones then act on their target cells to regulate their activity.  Unlike the nervous system, which causes a fast, specific response, the one hormone can affect the activity of many cells at the same time.


It is important for the body to have these two control systems because the nervous system is responsible mainly for rapid, immediate movement, such as skeletal muscle movement while the endocrine system is responsible for regulating a lot of the metabolic processes in the body, including cellular respiration.


Sources:
neuron picture from:
http://science.howstuffworks.com/environmental/life/human-biology/brain1.htm
endocrine system picture from: 
http://academic.kellogg.cc.mi.us/herbrandsonc/bio201_mckinley/endocrine%20system.htm
information from:
Elaine N. Marieb's Essentials of Human Anatomy & Physiology, Eighth Edition
https://docs.google.com/viewer?a=v&q=cache:pLygcenOGmsJ:www.angelo.edu/faculty/cadkins/Chp%252011%2520Control%2520Systems%2520of%2520the%2520Body.doc+control+systems+of+the+body&hl=en&gl=us&pid=bl&srcid=ADGEESjnS4rDPRFota_fUK0IVxBfnxaAhxkM67A8zn6hQAvTQanM0JGUS7BZEL72iuxRJ_lkw3cu_lRywmMN0KsoW6dzgfzoiDdKUPzh_6IRXLs7uMUZOfpm0lNiQKajteuzrfxf4jJ4&sig=AHIEtbRkIj6WxLjs0RmupHze3J-lSe08vQ&pli=1

Anatomy and Physiology: Diet Plan

My diet plan is supposed to be an energy-boosting diet that decreases carbohydrate intake.  I did not follow my diet plan for all four weeks mainly because I missed eating rice everyday.  It is also because there was free food during a competition that I went to and I decided to take advantage of that, even though the food totally did not fit the diet plan.  ^ ^


For my nutritional state, it might be too high in sodium and too low in calcium.  Based on the foods I ate, some of them might have been too oily or greasy.  Even though my diet plan is supposed to be an energy-boosting diet that decreases carbohydrate intake, I may have not cut down on carbohydrates enough as I tried to adapt the meals plan to the food I usually eat.

AP Bio: Three Key Ideas in Time, Love, Memory

Time
The concept of time is discussed mainly in Chapter 8: First Time.  It talked about how the flies in the experiment had a sense of time.  Konopka experimented with this in Benzer's laboratory and eventually discovered a gene that they called the "clock gene." It was the gene that controlled the flies' sense of time.  The flies had a routine of being active at sunup and stop moving at sundown, even if the room they were in was dark.  Without the gene, they did not follow this routine and would "wake and sleep at random intervals" (5).


Love
The concept of love is discusses mainly in Chapter 9: First Love.  It begins with the quote by William Blake, from "The Question Answer'd": "What is it men in women do require?  The lineaments of Gratified Desire.  What is it women in men do require?  The lineaments of Gratified Desire" (112).  The book goes on to explain that according to Darwin, reproduction is an important part in adaptation of survival.  It gives the chance for the more favorable genes to be expressed.  In the experiment in the book, flies have certain steps in their mating process.  They discovered that this chain of steps is controlled by a gene.  In other words, every step in the mating process is inherited.


Memory
The concept of memory is discussed mainly in Chapter 10: First Memory.  The book talks about how "evolution is learning" (132) and that "species store learning in chromosomes the way individuals store learning in their brains and societies store learning in books."  There is information that the flies would learn at the present time and the information that their ancestors had when life began.  The ability to learn and remember is also in their genes, for "the memory of discovery...has been passed down from generation to generation since near the beginning of life" (132).


Source: Time, Love, Memory: A Great Biologist and His Quest for the Origins of Behavior by Jonathan Weiner

Anatomy and Physiology: Lesson from Dead Men Do Tell Tales

The skeleton of Joseph Merrick the Elephant Man, a haunting image.  This picture was from: http://www.thebalde.net/edukia.php?uuid=152&lang=en.

After reading Dead Men Do Tell Tales, I learned that bones could tell a lot about the life of a person: the diseases they had, the injuries they sustained, how they died. . .
Because of this, bones could be very useful in solving murder cases or convicting a wanted criminal, as seen in the many cases that the author, William R. Maples, P.H.D., helped solve.
I would not be a forensic anthropologist because I feel that there is something very haunting and ghostly in looking at someone's remains who used to be a real, live person just like me.