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Throughout this whole school year, I have learned a lot not only about how the human body functions but also about the organisms around us. For example, there are many bacteria, fungus, viruses, and other living organisms surrounding us that we don't even know. Through this class, I was able to investigate what has been impossible to be seen from the naked eyes. The dissections that I've done in this class really interest me and it certainly did helped me confirmed my goal of becoming a bio-related doctor in the future. I never expected to have done all these hands-on activities in a science class ( all the dissections that we've done). I took Biology Honor freshmen year and all we dissected was an earthworm and a frog. In this class, we get to dissect a variety of stuff from a shark to a kidney. I have to say that I didn't really study from the book in this class at all, it was all the activities and labs that we did helped me learn about biology. The book is not interesting to read or even look at so all these fun stuff that we've done had helped me and many of my peers.

Genome Entries 10

Chapter 18: Cures

The is about genetic manipulation, and the first example is in 1972 Paul Berg made the first man made recombinant DNA by using restriction enzymes and ligase. After that, there have been several experiments using recombinant DNA where a retrovirus would be stripped of its infectious genes and replaced with a desired gene and then injected into the body either directly or through cultured cell, trying to cure various diseases through gene therapy such as SCID, hemophilia, cystic fibrosis, and cancer. Genetic engineering has very unnecessarily polarized its proponents and radical environmentalists, stemming from the issue of agricultural genetic engineering. Ridley explains the possibilities of human cloning with genetic improvement through the use of embryonic stem cells and recombinant DNA.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

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Chapter 17: Death
A gene called TP53 is responsible for suppressing rogue cancer cells and is classified as a tumor suppressor gene. These genes are the opposite of oncogenes, which are genes that encourage cell growth. Ridley explains that the reason detecting cancer early is so important is that the more it progresses and the more the cells divide, the more mutations accumulate. Some cancer victims also carry mutations in mutator genes. Ridley explains that in various types of cancers TP53 is mutated very early, which is why chemotherapy and radiation therapy does not always work effectively in later stages of the disease.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

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Chapter 15: Sex

Prader-Willi syndrome and Angelman’s syndrome, both are caused by the lack of the same chunk of chromosome 15, and it has been shown that whether a child inherits one syndrome or the other depends on the parent from whom the mutation is inherited. This relates to sexual antagonism and the fact that the placenta is controlled by paternal genes. Genetic cloning seems to erase all genetic imprints so the organism still survives. Imprinting has an effect on the brain too, that the mother’s genes control the development of the cerebral cortex while the father’s control the development of the hypothalamus, so essentially we inherit our mother’s way of thinking and our father’s innate moods.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

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Chapter 14: Immortality

James Watson discovered that polymerases do not start copying DNA at the tip of the chromosome, they start coding part way into the DNA. Telomerase is most likely responsible for increasing the continuous division of cells. Malignant cancer cells switch the gene on after it has been switched off by most cells in development. Ridley discusses why aging may be caused by evolution, and said that “Natural selection has designed all parts of our bodies to last just long enough to see our children into independence, no more.” So, cancer is most definitely linked to age.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

Genome Entries 6

Chapter 11: Personality

Dopamine is basically a motivational chemical, meaning that lack of it will make an individual lethargic or immobile, while excess can cause schizophrenia. Dean Hamer shows in a study that D4DR correlates with novelty seeking behavior. Additionally, therapists found that depathologizing people’s personalities and reassuring them that their personality is innate rather than some learned flaw helped them to improve their self-esteem. Personality and behavior can also be influenced by diet, specifically cholesterol intake. Antisocial and depressed people have been shown to have lower cholesterol levels, because there is a correlation between cholesterol and serotonin, a chemical similar to dopamine. Lower cholesterol levels mean lower serotonin levels which usually indicate depression or violent desires.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

Comparing 3 Invertebrates

Leeches

Many leeches found in lakes are parasites, feeding on the body fluids of fish and other creatures. Leeches can swim by undulating their body. However, mostly, they move by using the suckers at either end of their body to loop across the surface of objects. They eat the body fluids of of fish, frogs, water snails and insect larvae. They feed by attaching themselves to their prey and use either jaws or a proboscis to feed on blood. Fish wait for their victims by waiting outstretched. They are very difficult to see because they look just like plant stems. Leeches often consume more than their own body weight in a single meal and often rest, between meals, for up to a month.

Flatworms

Flatworms are unsegmented worms with flattened bodies. Their flatness allows them to shelter beneath stones. The surface of their bodies are covered with cilia which are kept in constant motion, allowing them to glide over plants and stones. They secrete slime which acts as a lubricant. They eat small animals including crustaceans, and insects, alive/dead. Their mouth is a small hole found halfway down the underside of their body. They can sense when food is around, because of sensory cells on their head. They extend a muscular tube out of their mouth, and suck up food. This tube is known as a pharynx. They are eaten by leeches and great diving beetles.

Earthworms

Earthworm bodies are divided into lots of different segments. Earthworms play an important role in helping to keep soil in good condition. They help to recycle plant material, and also mix oxygen into the soil as they tunnel. There are about 13 different types of earthworm in Britain.Earthworms move by contracting the circular muscles around their bodies, then the long muscles which run down their bodies. They eat mainly dead plant material. Earthworms sometimes drag leaves into their burrows and they eat the soil and use the dead plant material from it as food.

http://www.naturegrid.org.uk/biodiversity/invert_english.html

http://animals.nationalgeographic.com/animals/invertebrates/ 

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