Courses tagged with "Chemical reactions (stoichiometry)" (51)

As you learned in BIO101 [1], the cell is the fundamental unit of life; in fact, the smallest living organisms are composed of a single cell. We have learned that, despite their small size, cells are far from simple, and we have only recently begun to understand just how complex they are. This course will present you with a detailed overview of a cell’s main components and functions. Most of the units will cover topics familiar to you from BIO101, such as mitosis or the cell nucleus, but will explore them in greater depth. The course is organized roughly into four major areas: the cell membrane, cell nucleus, cell cycle, and cell interior. We will approach most of these topics straightforwardly, from a molecular and structural point of view. [1] http://www.saylor.org/courses/bio101a/…

Human physiology is the study of the body’s processes, also known as functions. You already have experience with this subject, because you are a human and perform numerous functions each day to maintain your body’s balance or homeostasis. For example, gas exchange in your lungs provides the body’s cells with adequate oxygen supply needed to survive and carry out metabolic processes. Digestion of food components in your mouth, stomach, and small intestines breaks larger substances into molecules that can be absorbed in the small intestines and used for energy. White blood cells attack foreign bodies, such as bacteria and cells containing viruses to keep you free from infection. As you might expect, an understanding of physiology is paramount if you wish to pursue studies in health care, development, or even behavior. A doctor needs to understand how to relate a urine sample to kidney function. A nurse needs to know the importance of electrocardiogram results and heart activity. A medical laboratory sci…

One of the best ways to understand the present is to understand the past. Evolutionary Biology is the study of the changes in life forms over time - changes that have occurred over millions of years as well as those that have occurred over just a few decades. In this course, we will look at the various mechanisms of evolution, how these mechanisms work, and how change is measured. The concepts you learn in this course will serve as a foundation for studying fossil records and current classification schemes in biology. We will begin the course by reviewing the evolutionary concepts of selection and speciation. We will then learn to measure evolutionary change through comparisons with the Hardy-Weinberg Equilibrium, to understand the process of change through Game Theory, and to interpret and classify changes by creating phylogenies. The course will wrap up with a look at the history of life according to the fossil record and a discussion of the broad range of life forms as they are currently classified. At the…

Cancer has existed among humans since humans themselves began and has been a subject of urgent interest from very early in our history.  What we call “cancer” consists of a number of different diseases with one fundamental similarity: they are all initiated by the unchecked proliferation and growth of cells in which the pathways and systems that normally control cell division and mortality are absent.  Cancer-cell abnormalities are often due to mutations of the genes that control the cell cycle and cell growth.  To understand cancer cells, then, one must first understand the processes that regulate normal cell cycles. This course will cover the origins of cancer and the genetic and cellular basis for cancer.  It will examine the factors that have been implicated in triggering cancers; the intercellular interactions involved in cancer proliferation; current treatments for cancer and how these are designed; and future research and treatment directions for cancer therapy.

Marine Biology is the study of ocean life.  As you might expect, life in salt water is vastly different from life in a terrestrial or freshwater environment due to factors like salinity, water circulation, and atmospheric pressure.  How, for example, can organisms living in salt water avoid dehydration?  How do organisms living in the depths of the ocean handle the immense pressure?  How do the environmental factors in marine communities affect biodiversity?  How do some animals manage to alternate between the demands of terrestrial life and the demands of marine life?  In this course, you will learn the answers to these questions and more.  This course will touch on a number of different subfields of biological study (including biochemistry, physiology, zoology, botany, and ecology) within the context of the ocean environment. You will start by learning about the ocean itself and its physical properties, as these properties influence the abundance, distribution, diversity, physiology, and behavior o…

Molecular biology studies the molecular mechanisms of life, particularly those responsible for genes and their expression.  In the center of molecular biology are the nucleic acids, DNA and RNA, and how they contribute to the synthesis of proteins. After a historical introduction (Unit 1), this course describes the basic types of DNA and RNA structure and the molecular interactions that shape them (Unit 2).  Unit 3 describes how DNA is packaged within the cellular nucleus as chromosomes; in eukaryotes the DNA coils around histones to form nucleosomes that comprise the chromatin of the chromosomes.  The next three units describe the core processes of molecular biology: replication of DNA (Unit 4), transcription of DNA into messenger RNA (Unit 5), and translation of messenger RNA into a protein (Unit 6).  These are followed by modifications of these basic processes: regulation of gene expression (Unit 7), DNA mutation and repair (Unit 8), and DNA recombination and transposition (Unit 9). The course conclu…

This lab course supplements BIO102: Introduction to Evolutionary Biology and Ecology [1].  Although we cannot virtually replicate a true lab experience, this “lab” will allow you to become familiar with scientific thinking and techniques, and will enable you to explore some key principles of evolutionary biology and ecology. The material in this lab supplement directly relates to the material covered in the lecture and reading portion of the course.  While the lecture and reading portion focuses on big-picture concepts, here we will focus more on visual understanding, application, and practical use of your knowledge.  In each unit, you will work through tutorials related to important scientific concepts and then will be asked to think creatively about how your knowledge can be put to practical or experimental use. [1] http:///courses/bio102/…

Botany is the study of plants.  Because species in the plant kingdom have characteristics that make them distinct from any other form of life, they are particularly interesting subjects for the study of evolution and physiology.  For example, whereas most organisms are dependent on other organisms for energy, plants can capture energy directly from photons of light and convert it into a usable form through the process of photosynthesis.  For this reason, plants are referred to as the “producers” in a habitat.  Unlike the cells of other organisms, plant cells have rigid cell walls constructed from the inside out (rather than the outside in) during mitosis and cytokinesis.  Plants also have a variety of unique reproductive and dispersal mechanisms that allow them to quickly adapt to, occupy, and invade far-flung areas, despite their general immobility. In this course, you will learn the basics of plant biology.  We will begin with plant anatomy, learning the names and functions of all of the parts o…

In this course, you will study microscopic anatomy. The study of the structure of a cell, tissue, organ, or related feature is known as anatomy. Gross anatomy (or macroscopic anatomy) involves examining anatomical structures that can be seen with the naked eye, whereas microscopic anatomy is the examination of minute anatomical structures that cannot be observed without the help of visual enhancement, such as a microscope. The terms microscopic anatomy and histology (the study of microscopic structure of animal and plant tissue) are used interchangeably. Many times it will be necessary to survey gross anatomy so that when you focus in on the microscopic anatomy you will have a geographical idea of the location within the body. This course makes use of microscope slides of anatomical structures to aid in the discussions of anatomy. Unit 1 begins with an overview of basic cell structure. The study of cells is known as cytology. Cells contain numerous structures that can only be seen with the aid of specialize…

Immunology is the study of our immune system, a highly sophisticated system that defends us against all disease-causing invaders by identifying and neutralizing such threats. Even though we might get sick every now and then, the immune system does an incredible job of warding off infection given how many infectious agents (thousands!) we come into contact with every day. This becomes most apparent when a healthy individual compares himself or herself to an individual with little or no immune response who cannot survive in a normal environment and must rely on specialized rooms much cleaner than even a surgery room. Before the discovery of immunity, we used to associate sickness and disease with various superstitions and beliefs. Only with the discovery of bacteria, viruses, and our own cells did scientists slowly piece together the modern theory of our immune system. Our overall system can be broken down into two sub-systems, each with its own unique cells, molecules, and functions. Our cells are in turn capa…

A thorough understanding of the systems of the body and the ways in which they fit together is imperative for study in many fields of biological inquiry, including medicine, physiology, developmental studies, and biological anthropology.  This course will provide you with an overview of the body from a systemic perspective.  Each unit will focus on one system, or network of organs that work together to perform a particular function.  At the end of this course, we will review the body from an integrative perspective, creating a more realistic vision of the ways in which the systems overlap.  We will also discuss current body imaging techniques and learn how to correctly interpret the images in order to put our newly-gained anatomical knowledge to practical use. This is a terminology-heavy course.  We will identify tissues and organ systems according to their functional and regional contexts, but information concerning the processes by which the tissues and organ systems actually function will be covered…

This course is a continuation of CHEM103 [1]: Organic Chemistry I.  As you progress through the units below, you will continue to learn the different chemical reactions characteristic of each family of organic compounds.  We will focus on four most important classes of reactions: electrophilic substitution at aromatic rings, nucleophilic addition at carbonyl compounds, hydrolysis of carboxylic acids, and carbon-carbon bond formation using enolates.  The enolate portion of this course will cover the reactivity of functional groups. We will also look at synthetic strategies for making simple, small organic molecules, using the knowledge of organic chemistry accumulated thus far.  At the end of this course, you will possess the tools you need to plan the synthesis of fairly complicated molecules, like those used in pharmaceutics.  From the perspective of a synthetic organic chemist, the two most challenging aspects of synthesizing drug molecules are the incorporation of  "molecular rings" (rings of 5, 6,…

Physics 101 is the first course in the Introduction to Physics sequence. In general, the quest of physics is to develop descriptions of the natural world that correspond  closely to actual observations.  Given this definition, the story behind everything in the universe is  one of physics.  In practice,  the field of physics is more often limited to the discovery and refinement of the basic laws that underlie the behavior of matter and energy.  While biology is founded upon physics, in practice, the study of biology generally assumes that the present understanding of physical laws is accurate.  Chemistry is more closely dependent on physics and   assumes that physical laws provide accurate predictions.  Engineering, for the most part, is applied physics. In this course, we will study physics from the ground up, learning the basic principles of physical laws, their application to the behavior of objects, and the use of the scientific method in driving advances in this knowledge.  This first course o…

Neurobiology is all about the biology of our nervous system, from the spinal cord to the brainand everything in between. The nervous system allows us to have conscious thoughts, enables us to learn, and gives us voluntary control of our muscles. Our understanding of neuroscience begins with the ancient Egyptians, who practiced surgical drilling to treat certain neurological disorders. The earliest philosophers believed that the heart (not the brain) was the center of consciousness and intelligence. As scientific knowledge matured and developed, philosophers disproved that belief but discovered that there is much more to neurobiology than “the brain.” Researchers found that there are literally hundreds of billions of nerves and other cells that cooperate and share information to make the nervous system work. Accordingly, neurobiology is an extremely complex field of study. This course is designed to provide you with an overview of the most important areas of neurobiological study. We will not pay much…

This lab course supplements BIO304: Human Physiology [1].  Although we cannot virtually replicate the lab experience, this “lab” will familiarize you with scientific thinking and techniques and will enable you to explore of some key principles of human physiology. The material in this lab supplement relates to the material covered in the lecture and reading portion of the course.  While the lecture and reading portion focuses on big-picture concepts, here we will focus more on visual understanding, manipulation, and practical use of your knowledge.  You will review the physiology of the organ systems by using images of models, experiments, and videos.  Then you will be asked to assess your knowledge, which eventually can be put to practical or experimental use. Co-requisite: BIO304: Human Physiology [2]. [1] http://www.saylor.org/courses/bio304/ [2] http://www.saylor.org/courses/bio304/…

Organic chemistry is a branch of chemistry that focuses on a single element: carbon!  Carbon bonds strongly with other carbon atoms and with other elements, forming numerous chain and ring structures.  As a result, there are millions of distinct carbon compounds known and classified.  The vast majority of the molecules that contain carbon are considered organic molecules, with few debatable exceptions such as carbon nanotubes, diamonds, carbonate ions, and carbon dioxide.  Carbon is central to the existence of life as it is an essential component of nucleic acids (DNA and RNA), sugars, lipids, and proteins.  A well-rounded student of science must take courses in organic chemistry to understand its application to various topics, such as the study of polymers (plastics and other materials), hydrocarbons, pharmaceuticals, molecular biology, biochemistry, and other life sciences. In the first semester of organic chemistry, you will learn the basic concepts needed to understand the three-dimensional structu…

Even in ancient times, scholars believed that diseases could be spread by organisms too small to be seen by the naked eye. Before we discovered that bacteria cells were the real culprits, many attributed disease to other sources. Now that scientists have definitively identified the microscopic causes of various infectious diseases, microbiology, or the study of microscopic-sized organisms, has become an increasingly important field in biology and in the larger biomedical community. Most microbes are harmless. Some of them are essential for life on Earth, e.g. through their ability to fix nitrogen. Biotechnology, which is truly the industry of our times, takes advantage of microbes for the production of a variety of complex substances, and it also mass-produces natural and engineered microbes for human use. This course will cover a range of diverse areas of microbiology, including virology, bacteriology, and applied microbiology. This course will focus on the medical aspects of microbiology, as medical res…

Ecology is the study of interactions between organisms and between organisms and their environments.  Population ecology is the subfield of ecology that identifies those ecological factorsin the community or in the ecosystemthat regulate a population’s size. Ecosystems and communities involve complex interactions that have evolved over long periods of time.  The species that are present and the interactions we see between them are the result of evolution under the unique environmental pressures that exist in a given environment.  These interactions may be delicately intertwined, such that the loss of a single species from a community could mean the collapse of the entire community in a domino effect.  Thus, biologists are concerned with the preservation of biodiversity in ecosystemsretaining as many different species in the ecosystem as possible so the intricate relationships among species are preserved. In recent years, we have seen a decrease in the biodiversity of ecosystems.  Human activities a…

In this course, you will look at the properties behind the basic concepts of probability and statistics and focus on applications of statistical knowledge.  You will learn about how statistics and probability work together.  The subject of statistics involves the study of methods for collecting, summarizing, and interpreting data.  Statistics formalizes the process of making decisions, and this course is designed to help you use statistical literacy to make better decisions.  Note that this course has applications for the natural sciences, economics, computer science, finance, psychology, sociology, criminology, and many other fields. We read data in articles and reports every day.  After finishing this course, you should be comfortable evaluating an author's use of data.  You will be able to extract information from articles and display that information effectively.  You will also be able to understand the basics of how to draw statistical conclusions. This course will begin with descriptive statistic…

Biochemistry is the study of the chemical processes and compounds, such as cellular makeup, that bring about life in organisms.  It is a combination of multiple science fields; you can think of it as general and cell biology coupled with organic and general chemistry.  Although living organisms are very complex, from a molecular view, the material that constitutes “life” can be broken down into remarkably simple molecules, much like the breakdown of our English language to the English alphabet.  Although there exists thousands upon thousands of molecules, they all breakdown into four core components: nucleic acids, amino acids, lipids, and carbohydrates.  As we can make hundreds of thousands of words from just 26 letters, we can make thousands of different biomolecules from those 4 components.  For example, the human genome, containing the necessary information to create a human being, is really just one very long strand of 4 different nucleotides. This course is structured around that approach, so…