8 Major Themes Of Biology
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Publicado: 17 de agosto de 2011
8 MAJOR THEMES OF BIOLOGY
2ND Sem. Final Exam/ M Stalzer
Science as a Process- Is a way of knowing. It can involve a discovery process through inductive reasoning or experimentation.
a.Molecules and Cells
All organisms are composed of one or more cells. The cell is the basic unit of life.
Calvin’ collaborative
Cells come from preexisting cells.
Plasma membrane
Investigations in the1920's concluded that the plasma membrane is indeed a phopholipid bilayer. In the 1970's the fluid-mosaic model of the membrane was developed. This model depicts the membrane as a fluid structure in which is embedded proteins and cholesterol.
b. Heredity and Evolution
Human Genome Project
A genome is the entire DNA in an organism, including its genes. Genes carry information for making allthe proteins required by all organisms. These proteins determine, among other things, how the organism looks, how well its body metabolizes food or fights infection, and sometimes even how it behaves. DNA is made up of four similar chemicals (called bases and abbreviated A, T, C, and G) that are repeated millions or billions of times throughout a genome. The human genome, for example, has 3 billionpairs of bases. The particular order of As, Ts, Cs, and Gs is extremely important. The order underlies all of life's diversity, even dictating whether an organism is human or another species such as yeast, rice, or fruit fly, all of which have their own genomes and are themselves the focus of genome projects. Because all organisms are related through similarities in DNA sequences, insights gainedfrom nonhuman genomes often lead to new knowledge about human biology.
Development of DNA
Mendel did extensive work with pea plants, and set down the framework for our current understanding of patterns of inheritance. He recognized dominant and recessive forms, or phenotypes, controlled by what he called factors. We now call these differing forms of genes alleles. Mendel's law of segregationstates that a pair of alleles becomes separated during the formation of gametes, and that each gamete only contains one allele for each trait. (We now know that meiosis is the process by which alleles separate, and that polygenic inheritance means that a trait can be controlled by more than one gene.) His law of independent assortment states that alleles are separated into gametes randomly - theway in which one pair of alleles separates does not affect the separation of another pair. It was not until later that the concept of linkage was realized. From his studies, it has been established that there is always a common ratio in the two following crosses. They proposed that the two strands run in opposite directions. The phosphate and sugar backbone of each chain winds around the outside,and the bases project into the center. The bases, and strands, are connected by hydrogen bonds that can easily be broken for replication and transcription.
Organisms and Populations
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Human Impact on the Biosphere
Role of Roof and leaves
Human activity damages the biosphere. Exponential population growth, destruction of habitats for agriculture and mining, pollution from industry andtransportation, and many other activities all contribute to the damage of the environment. Some of the destructive consequences of human activity are summarized as follows, Greenhouse effect. The burning of fossil fuels and forests increases CO2 in the atmosphere. Increases in CO2 cause more heat to be trapped in the earth’s atmosphere. As a result, global temperatures are rising. Warmer temperaturescould raise sea levels (by melting more ice) and decrease agriculture output (by affecting weather patterns).
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|
|
Energy Transfer
Energy is required for all processes that make life possible. Organisms obtain energy from the environment and use it to carry out chemical reactions. Energy is also required for maintaining homeostasis within an organism and providing regulation...
2ND Sem. Final Exam/ M Stalzer
Science as a Process- Is a way of knowing. It can involve a discovery process through inductive reasoning or experimentation.
a.Molecules and Cells
All organisms are composed of one or more cells. The cell is the basic unit of life.
Calvin’ collaborative
Cells come from preexisting cells.
Plasma membrane
Investigations in the1920's concluded that the plasma membrane is indeed a phopholipid bilayer. In the 1970's the fluid-mosaic model of the membrane was developed. This model depicts the membrane as a fluid structure in which is embedded proteins and cholesterol.
b. Heredity and Evolution
Human Genome Project
A genome is the entire DNA in an organism, including its genes. Genes carry information for making allthe proteins required by all organisms. These proteins determine, among other things, how the organism looks, how well its body metabolizes food or fights infection, and sometimes even how it behaves. DNA is made up of four similar chemicals (called bases and abbreviated A, T, C, and G) that are repeated millions or billions of times throughout a genome. The human genome, for example, has 3 billionpairs of bases. The particular order of As, Ts, Cs, and Gs is extremely important. The order underlies all of life's diversity, even dictating whether an organism is human or another species such as yeast, rice, or fruit fly, all of which have their own genomes and are themselves the focus of genome projects. Because all organisms are related through similarities in DNA sequences, insights gainedfrom nonhuman genomes often lead to new knowledge about human biology.
Development of DNA
Mendel did extensive work with pea plants, and set down the framework for our current understanding of patterns of inheritance. He recognized dominant and recessive forms, or phenotypes, controlled by what he called factors. We now call these differing forms of genes alleles. Mendel's law of segregationstates that a pair of alleles becomes separated during the formation of gametes, and that each gamete only contains one allele for each trait. (We now know that meiosis is the process by which alleles separate, and that polygenic inheritance means that a trait can be controlled by more than one gene.) His law of independent assortment states that alleles are separated into gametes randomly - theway in which one pair of alleles separates does not affect the separation of another pair. It was not until later that the concept of linkage was realized. From his studies, it has been established that there is always a common ratio in the two following crosses. They proposed that the two strands run in opposite directions. The phosphate and sugar backbone of each chain winds around the outside,and the bases project into the center. The bases, and strands, are connected by hydrogen bonds that can easily be broken for replication and transcription.
Organisms and Populations
|
Human Impact on the Biosphere
Role of Roof and leaves
Human activity damages the biosphere. Exponential population growth, destruction of habitats for agriculture and mining, pollution from industry andtransportation, and many other activities all contribute to the damage of the environment. Some of the destructive consequences of human activity are summarized as follows, Greenhouse effect. The burning of fossil fuels and forests increases CO2 in the atmosphere. Increases in CO2 cause more heat to be trapped in the earth’s atmosphere. As a result, global temperatures are rising. Warmer temperaturescould raise sea levels (by melting more ice) and decrease agriculture output (by affecting weather patterns).
|
|
|
Energy Transfer
Energy is required for all processes that make life possible. Organisms obtain energy from the environment and use it to carry out chemical reactions. Energy is also required for maintaining homeostasis within an organism and providing regulation...
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