DNA and Genomics Project

Attribution: http://www.ted.com/talks/lang/eng/spencer_wells_is_building_a_family_tree_for_all_humanity.html


Abstract

Spencer Wells studies human diversity, and how humanity derived from a single common source and has become so astonishingly widespread. He answers these sub-questions to help understand this broad topic of diversity. Do we all share a common origin, and if so when and how long ago did we originate? Also, how did we become to occupy every corner of the globe? Instead of guessing about our ancestry, he constructs a family tree for humankind far back until the very earliest days of our species by using DNA. Wells has concluded that all humans alive today are descended from a single man who lived in Africa around 60,000 to 90,000 years ago. Now, Wells is working on the question: How did this man, sometimes called "Ychromosomal Adam," become the multicultural body of life known as humanity? 

Biography of Spencer Wells:
Spencer Wells was born on April 6, 1969 in Georgia, United States. He is a geneticist, anthropologist, and an Explorer-in-Residence at the National Geographic Society. He wrote the book The Journey of Man: A Genetic Odyssey, which explains how genetic data has been used to trace human migrations over the past 50,000 years, when modern humans first migrated outside of Africa. Wells also wrote and presented the PBS/National Geographic documentary of the same name. By analyzing DNA from people in all regions of the world, Wells has concluded that all humans alive today are descended from a single man who lived in Africa around 60,000 - 90,000 years ago. Since 2005, Wells has headed The Genographic Project, undertaken by the National Geographic Society, IBM, and the Waitt Family Foundation, which aims to creating a picture of how our ancestors populated the planet by analyzing DNA samples from around the world. He presents the knowledge gained from the project around the world, including at the 2007 TED conference, where he spoke specifically about human diversity. Wells is quoted saying "As often happens in science, technology has opened up a field to new ways of answering old questions—often providing startling answers.”

Attributions: 

http://en.wikipedia.org/wiki/Spencer_Wells
http://www.nationalgeographic.com/field/explorers/spencer-wells.html

Vocabulary:
Paleoanthropology- the study of the origins and predecessors of the present human species, using fossils and other remains.


Genealogy- a record or account of the ancestry and decent of a person, family, or group.


Homo erectus-an extinct species of the human lineage, formerly known as Pithecanthropus erectus, having upright stature and a well- evolved skeleton, but with a smallish brain, low forehead, and protruding face.


Indigenous- originating in and characteristic of a particular region or country; native.


Double helix- The shape of DNA, much like a spiral staircase or twisted ladder. The stairway's railings are composed of sugars and phosphates. Its sides contain the patterned base pairs: A, T, C, and G.


DNA- Deoxyribonucleic acid: a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information


Morphology-  the study of the form, structure and configuration of an organism. This includes aspects of the outward appearance (shape, structure, colour, pattern) as well as the form and structure of the internal parts like bones and organs.


Haploid- of a cell or organism having a single set of chromosomes


Genome- The ordering of genes in a haploid set of chromosomes of a particular organism


Chromosome-a threadlike strand of DNA in the cell nucleus that carries the genes in a linear order


Nucleotide- Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA.

http://dictionary.reference.com/ 

Theme 1: Evolution

Spencer Wells explains that all human beings share a common region and eventually spread to occupy every corner of the globe.  Charles Darwin states that the human species originated from our biggest allies gorillas and chimpanzees, living in Africa around 23 million years ago. However our human ancestry shares a common ancestor with every living thing on earth due to DNA, which ties us all together. Carolus Linnaeus was the first to use morphology, which helped him categorize every living thing on the planet, and discover 12,000 different species. Based on morphology human races had been diverging from each other for over millions of years since the time of Homo erectus. Written in our DNA we have a historical document that takes us back to the very earliest days of our species. As our DNA is being passed on through generations, mistakes rarely occur. These rare changes become a marker of decent.  If you share a marker with someone it means u share an ancestor with someone in the past that first showed the change of DNA. The pattern of these markers and when they occurred helped construct a family tree for everyone alive today. The deepest lineage in our tree is in Africa, which means we originated from Africa because they have been diverging for the longest time. At some point in time a group of Africans left the African continent to help populate the rest of the world. Within the last 200,000 years we all share a single woman ancestor in Africa. The male ancestor only lived 60,000 years ago. It’s only within the last 60,000 years diversity has accumulated.

Theme 2: Continuity and Change 

60,000 years ago humans began to accumulate in Africa. During this time period the last ice age was occurring. Africa wasn’t covered in ice unlike the rest of the world, rather Africa was drying out. The whole world was drying out and Africa was turning into dessert because ice sucks moisture out of the atmosphere. The population crashed to fewer than 2,000 individuals. The human population nearly went extinct. Then luckily art made its appearance and humans began to specialize and expand. Their level of intelligence increased tremendously and they began to use languages and create intricate tools. This change in behavior allowed us to survive these harsh conditions in Africa and expand around the world. Eventually 6000 different languages were created and 6 in a half billion diverse people evolved. 

Trimester one reflections:

    This is what I learned about.........

Throughout this trimester I learned many things that I fully understand and could explain thoroughly. The properties of water: Cohesion and Adhesion, Temperature moderation, Low density of Ice, waters ability to dissolve other substances, and the PH scale all make sense to me. A carbohydrate is an organic compound made up of sugar molecules. A monosaccharide are simple sugar that contain one sugar unit. A disaccharide consists of a double sugar unit, and a polysaccharide are long polymer chains made up of simple sugar monomers. I learned the characteristics of Lipids which include fats and steroids, Proteins which perform most functions in cells, and enzymes and how they work. In chapter 6.1 i learned the three different types of microscopes: light, scanning, and transmission. A light shows the interior of the cell, its not very detailed, scanning shows cells surface, and transmission shows internal details of a preserved cell. I know the difference between an Animal and a plant cell. I also learned each organelle and their function in a cell, and how membranes regulate the traffic of molecules through active and passive transport. The cell cycle consists of interphase and mitotic phase.  In the mitotic phase the cell divides within each step: prophase, metaphase, anaphase, and telophase/ cytokinesis. Meiosis instead of producing two cells, produces four. Also it has to do with the division of the sex cells. 

What I have found difficult about what I have studied is.........

Im still fuzzy on the building and breaking polymers, I know the definition of a monomer and polymer but the process confuses me. Also Meiosis is still confusing to me, it makes sense that its the reproduction of the sex chromosomes and it produces a haploid, but the whole process put together confuses me. Also I don't understand how tetrads are produced. The difference between Homologous chromosomes and sister chromatids also tend to confuse me. 

How is structure related to function?

Structure is related to function in so many ways... In the cell each organelle has a specific function and without that function the body wouldn't be able to carry out it's necessary routines. The structure in reproduction is crucial to the end result. Every step in mitosis and meiosis has it's own function in reproduction. In interphase DNA has duplicated and it consists of check points G1, S phase, and G2. Mitotic phase is where the division takes place in the process of Prophase, metaphase, anaphase, telophase and cytokinesis. Structure is key to the outcome result of it's function in both organelles and reproduction. 

Reflections:

1. What I learned was that membranes are not only cell dividers but also regulte the transport of substances across the boundary, allowing only certain substances to pass. Membranes are fluid like and not rigid sheets. Phospholipids form a phospholipid bilayer which is two layers of molecules that surround the organelle or cell. The proteins perform most of the membranses specific functions.Also transport proteins help move certain substances across the membrane. Molecules are constantly in motin, a result of this is diffusion. A selectively permeable membrane allows some substances to cross the membrane more easily than others and blocks the passage of some substances altogether. Facilitated diffusion is when transport proteins provide a pathway for certain molecules to pass. Diffusion across a membrane is caleld passive transport because no energy is expended by the cell. An isotonic solution is when the concentration of solute in a solution are equal. Hypertonic is a solution with a higher concentration of solute, and Hypotonic is a solution with a lower concentration of solute. In animal cells, in a hypotonic solution the cells gain water, swell and may even pop. In a hypertonic solution the cells lose water and shrivel and may die. A plant cell is firm and healthiest in a hypotonic environment. A plant cell in an isotonic environment it becomes limp. In a hypertonic environment a plant cell loses water and it dies. Active transport is when the cell expends energy to move molecules across the membrane.  Large particles depend on vesiciles to get into out of and within a cell.



2. What i have found difficult to understand is the process of Osmosis. I get the definitions of hypertonic, hypotonic, and isotonic. But i dont understand the result of osmosis when it involves hypertonic, hypotonic and isotonic.

3. Living organisms utilize energy to do work by Active transport,when a cell expends energy to move molecules across the membrane. During Actve transport a specific transport protein pumps a solute across a membrane usually in the opposite direction to the way it travels in diffusion.

Jello

Ingredients:
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3.sugar or atificial sweetener and artificial flavors
4. food coloring