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Introduction and Cell Membrane Introduction and Cell Membrane Peter Takizawa Department of Cell Biology Topics for today’s lecture • Course organization • Why cell biology • Cell membrane Cell Biology comprises a variety of activities that discuss basic science and disease. Lectures Website Cell Biology Clinical Histology Correlations Website !The Cell Biology course proper consists of three distinct activities: lectures, histology labs and clinical correlations. In addition, there are two electives that are associated with Cell Biology: molecular and cellular basis of disease and bench to bedside. Lectures will discuss the principles and concepts of modern cellular and molecular biology, focusing on the systems and mechanisms that allow cells to survive and perform specific functions in our bodies. The first part of the course will discuss the !systems and mechanisms that are common to most cells. The second part will discuss how the different types of cells in our bodies, utilize and modify those systems to perform specific biological functions. Histology examines the structure and functions of cells and how cells form tissues and organs. Histology places the cellular mechanisms presented in lecture into the context of cell and tissue structure. Histology also demonstrates how the !organization of cell and tissues allows organs to perform the physiological functions. Clinical correlations introduce students to clinical topics and medical terminology and demonstrate connections between basic science and disease. These presentations by physician-scientists, who are leaders in their fields, will sometimes include patients. You will notified when a patient is present. Why study cell biology to be a physician In order to understand how disease arises and how to treat disease, we need to learn how we work under normal conditions. You must first appreciate how something is suppose to work before determining how it is broken. To understand how we work, how our bodies function under normal conditions, we must learn how the fundamental unit of life works. That unit is the cell. The cell is the fundamental unit of life. What we mean when we say that the cell is the fundamental unit of life is that cells are the smallest unit capable of growth, replication and adapting to the environment. These principles are exhibited by the many different types of single cells !organisms, such as bacteria and yeast, which grow and divide on their own and respond to changes in the environment to survive. But even cells from multicellular organisms, like ourselves, can survive as individual cells and under appropriate conditions, grow and divide. This second image shows human cells growing as individual cells in culture. These are HeLa cells whose initial progenitor was taken in 1951 from Henrietta Lacks who was diagnosed with cervical cancer and had a portion of the cancer was removed and the cells cancerous cultured in petri dishes. Descendants from these cells are growing and dividing !today and are widely used in biomedical research. The fact that cells can grow and adapt to environmental changes makes them fascinating subjects of study for those interested in biology and science. But why is cell biology important for medical professionals and physicians in particular? The cell is the fundamental unit of life. What we mean when we say that the cell is the fundamental unit of life is that cells are the smallest unit capable of growth, replication and adapting to the environment. These principles are exhibited by the many different types of single cells !organisms, such as bacteria and yeast, which grow and divide on their own and respond to changes in the environment to survive. But even cells from multicellular organisms, like ourselves, can survive as individual cells and under appropriate conditions, grow and divide. This second image shows human cells growing as individual cells in culture. These are HeLa cells whose initial progenitor was taken in 1951 from Henrietta Lacks who was diagnosed with cervical cancer and had a portion of the cancer was removed and the cells cancerous cultured in petri dishes. Descendants from these cells are growing and dividing !today and are widely used in biomedical research. The fact that cells can grow and adapt to environmental changes makes them fascinating subjects of study for those interested in biology and science. But why is cell biology important for medical professionals and physicians in particular? The cell is the fundamental unit of life. What we mean when we say that the cell is the fundamental unit of life is that cells are the smallest unit capable of growth, replication and adapting to the environment. These principles are exhibited by the many different types of single cells !organisms, such as bacteria and yeast, which grow and divide on their own and respond to changes in the environment to survive. But even cells from multicellular organisms, like ourselves, can survive as individual cells and under appropriate conditions, grow and divide. This second image shows human cells growing as individual cells in culture. These are HeLa cells whose initial progenitor was taken in 1951 from Henrietta Lacks who was diagnosed with cervical cancer and had a portion of the cancer was removed and the cells cancerous cultured in petri dishes. Descendants from these cells are growing and dividing !today and are widely used in biomedical research. The fact that cells can grow and adapt to environmental changes makes them fascinating subjects of study for those interested in biology and science. But why is cell biology important for medical professionals and physicians in particular? The cell is the fundamental unit of life. What we mean when we say that the cell is the fundamental unit of life is that cells are the smallest unit capable of growth, replication and adapting to the environment. These principles are exhibited by the many different types of single cells !organisms, such as bacteria and yeast, which grow and divide on their own and respond to changes in the environment to survive. But even cells from multicellular organisms, like ourselves, can survive as individual cells and under appropriate conditions, grow and divide. This second image shows human cells growing as individual cells in culture. These are HeLa cells whose initial progenitor was taken in 1951 from Henrietta Lacks who was diagnosed with cervical cancer and had a portion of the cancer was removed and the cells cancerous cultured in petri dishes. Descendants from these cells are growing and dividing !today and are widely used in biomedical research. The fact that cells can grow and adapt to environmental changes makes them fascinating subjects of study for those interested in biology and science. But why is cell biology important for medical professionals and physicians in particular? We are made entirely of cells and material produced by cells. !We are made entirely of cells and the material that cells produce. All of the activities and properties that allow us humans to grow, proliferate and adapt to our environment are generated by the cells in our body. For example, we all need to eat to obtain nutrients. Part of that process requires that we digest our food and then process the resulting small molecules: storing them we don’t need them and releasing them when we do. It would also be helpful if we had a way of handling any toxic material that we ingest with our food. One organ plays a central role in these processes: the liver. The liver helps with digestion and absorption of food, especially lipids. It processes most of the nutrients we obtain !from food, storing those that aren’t needed and releasing them when they are. It also detoxifies chemicals that are harmful to our bodies. If we look for these activities in the liver by dissecting it and looking it a portion, we find a mass of material. Zooming in on that material, we see mostly cells. These cells are called hepatocytes. All the critical physiological functions that are performed !by the liver, that are essential for our survival, are performed by these cells. ! We are made entirely of cells and material produced by cells. !We are made entirely of cells and the material that cells produce. All of the activities and properties that allow us humans to grow, proliferate and adapt to our environment are generated by the cells in our body. For example, we all need to eat to obtain nutrients. Part of that process requires that we digest our food and then process the resulting small molecules: storing them we don’t need them and releasing them when we do. It would also be helpful if we had a way of handling any toxic material that we ingest with our food. One organ plays a central role in these processes: the liver. The liver helps with digestion and absorption of food, especially lipids. It processes most of the nutrients we obtain !from food, storing those that aren’t needed and releasing them when they are. It also detoxifies chemicals that are harmful to our bodies. If we look for these activities in the liver by dissecting it and looking it a portion, we find a mass of material. Zooming in on that material, we see mostly cells. These cells are called hepatocytes. All the critical physiological functions that are performed !by the liver, that are essential for our survival, are performed by these cells. ! We are made entirely of cells and material produced by cells. !We are made entirely of cells and the material that cells produce. All of the activities and properties that allow us humans to grow, proliferate and adapt to our environment are generated by the cells in our body. For example, we all need to eat to obtain nutrients.
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