BI 123 Week 2 Notes
BI 123 Week 2 Notes BI 123
Popular in Biology of Cancer
Popular in Biology
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
This 5 page Class Notes was uploaded by Rachel Kasashima on Saturday January 16, 2016. The Class Notes belongs to BI 123 at University of Oregon taught by Dr. Kelly in Fall. Since its upload, it has received 26 views. For similar materials see Biology of Cancer in Biology at University of Oregon.
Reviews for BI 123 Week 2 Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 01/16/16
Chapter 2: The Cell Key Terms: nucleus: The large membrane-bound organelle within a cell housing the chromosomes. chromosome: A structure composed of DNA and associated protein that carries genes. prokaryote: A singe-celled organism characterized by the lack of a nucleus.The chromosome of a prokaryote is not contained within a membrane-bound compartment. eukaryote: An organism that is comprised of one or more cells that contain a nucleus. organelle: A membrane-bound compartment that has a specialized function within a cell. Cellular anatomy cytoplasm: A viscous ﬂuid that makes up the interior of the cell,excluding the nucleus. cell membrane/cytoplasmic membrane:A thin membrane that serves as the cell's exterior border, surrounding all the internal components of the cell. receptor: A protein,usually located on the cytoplasmic membrane of a cell,that binds with with a molecule at the cell's exterior.The binding of such a molecule initiates chemical signaling within the cell to induce a physiological or genetic response. Organisms are made of one cell or of many cells unicellular: Description of an organism that is composed of a single cell. multicellular: Description of an organism that is composed of many cells;the cells usually cluster into different groups that form tissues with unique functions. tissue: A group of cells that serve a common function. organ: A tissue or collection of tissues that serves a unique function for the organism. Stem cells and differentiation differentiation: The maturation of a cell,including changes in shape and physiology,into a speciﬁc,ﬁnal form. stem cell: A cell that regenerates itself during division while also giving rise to a daughter cell with a speciﬁc fate. self-renewal: The result of a cell division that yields one daughter cell that is identical to the mother cell, thereby perpetuating the mother cell through endless rounds of division. fate (cellular): The ﬁnal destiny,in terms of form and function,of a cell. adult stem cell: A specialized stem cell that regenerates itself during division while also giving rise to a daughter cell with a partially restricted fate,such as that of the blood cell lineages. progenitor cells: A daughter cell from a stem cell whose descendants undergo limited divisions before differentiating. Cell division Chromosome structure diploid: The state of bearing two copies of each chromosome. homologous chromosomes: Chromosomes that are similar in size,shape,and gene content and order.In a diploid organism homologous chromosomes exist as pairs. karyotype: The chromosomal content of a cell or organism. sister chromatid: Each strand of a duplicated chromosome. centromere: A region of a duplicated chromosome at which sister chromatids remain connected until anaphase of mitosis. Mitosis mitosis: The division of the nucleus into two identical nuclei that will be partitioned into two daughter cells following cell division (cytokinesis). interphase: Non-dividing period of mitosis. prophase: The period of mitosis where condensation of the chromosomes into thick arms and by the apparent disintegration of the nucleus membrane occurs. spindle ﬁbers: Thin threads that attach to the centromeres of the chromosomes. prometaphase: The period of mitosis when the chromosomes align into the middle of the cell. metaphase: The phase when chromosomes have ceased their random movements and are distributed in the middle of the cell. anaphase: The period of mitosis when two sister chromatids of each duplicated chromosome are pulled apart by opposing spindle ﬁbers,with each chromatid moving to the opposite pole of its sister. telophase: When the chromosomes have ﬁnished their poleward migration and new nuclear membranes form around each cluster of chromosomes.It takes on the appearance of interphase nuclei seen prior to mitosis. cytokinesis: The actual splitting of the cell so that the cytoplasm is equally partitioned into two new cells. Abnormalities in division nondisjunction: The failure of chromatids or chromosomes to correctly segregate during division. aneuploidy: The state of having an abnormal number of chromosomes. deletion (chromosomal): Loss of a portion of a chromosome. translocations: A relocation of a portion of one chromosome to a non-homologous (different) chromosome. A reciprocal translation describes the exchange of chromosome segments between two chromosomes. The cell cycle cell cycle: The series of states that describe the normal growth and division cycle of the cell. generation time: The time required for a cell to undergo a complete division. G1 (Gap 1) phase: The phase of the cell cycle following the completion of mitosis and preceding duplication of the chromosomes: S (synthesis) phase: The phase of the cell cycle during which chromosomes are duplicated. G2 (Gap 2) phase: The phase of the cell cycle following chromosome duplication and preceding mitosis. M (mitosis) phase: The phase of the cell cycle during which mitosis occurs. G0 (Gap 0) phase: A phase of the cell cycle that is considered a temporary or permanent exit from the G1 phase.Cells in G0 are physiologically active,but do not undergo cycles of division. checkpoint: A control point in the cell cycle at which a pause may be induced if cellular conditions are not sufﬁcient for cell advancement. Asymmetric division:creating different types of cells Leukemia: a cancer of the blood leukemia: A cancer of the blood forming tissue in the marrow characterized by overproduction of white blood cells. Myeloid: Of the blood cell lineage leading to granulocytes,red cells,macrophages,and platelet-forming cells. Lymphoid: Of the lymphatic system or of the lymphocyte blood cell lineage. Cancerous marrow cells Myeloid leukemias: Overproduction of cells of the myeloid blood cell lineage. Lymphoid leukemias: Overproduction of cells of the lymphoid blood cell line (B orT cells). Acute leukemia Chronic leukemia Some Deﬁnitions • Tumor (Neoplasm): A(n) abnormal mass of cells formed through uncrowned cell division. Neoplasm -> (new + something formed/molded) • Benign: Conﬁned to a speciﬁc site within a tissue,and gives no evidence of envision to adjacent tissue. Generally just treated with surgery.Benign tumors do not come back. • Malignant: Shows evidence of,or potential for,movement or invasion to adjacent tissues or anatomically distant sites. =CANCER A malignancy is a cancerous tumor or condition • Metastasis (n): The process by which cancer cells move from the original tumor to distant sites;also,a cancerous grown that arose from a distant source. Can be described as a process and a structure Meta = "next";stasis = "placement" • Metastasize (v): To move from the original site (e.g.Colon cancer often metastasizes ﬁrst to the liver) • Carcinoma: Cancer that originates from epithelium (plur:eplithelia) • Eplithelia: Sheet of cells that cover all surfaces and line glands. • Gland: Organ or tissue that secretes a substance into the blood or other spaces. • Sarcoma: Cancer that arises from cells of connective and supportive tissues. • Lymphoma, Leukemia, and Multiple Myeloma: Cancers that arise from blood-producing cells in the bone marrow. • Leukemia: Overproduction of white blood cells (leukocytes) • Leukocytes: White blood cells • Multiple Myeloma: Tumor of plasma lymphocytes • Lymphoma: Tumor of the lymphatic system. • Lymphatic system: A network of tubes (ducts) and intersections (nodes) that drains liquid (lymph) from tissues and returns it to the blood. • Lymph: The colorless ﬂuid that circulates through the lymphatic system and contains white blood cells. • -oma: sufﬁx that means tumor Usually implies a benign tumor ‣ For example: • Adenoma:mass of glandular tissue adeno - "gland" • Fibroma:mass of connective tissue ﬁbro - "ﬁber" • Lipoma:mass of fat cells lipo - "fat" • Osteoma:mass of bone tissue osteo - "bone" Prevailence of main cancer groups • Carcinomas: 90% External epithelia:in contact with external environment (e.g.Skin,respiratory,respiratory tracts, digestive) 55% Internal epithelia:line glands (e.g.Breast,thyroid,ovary,prostate,etc.) 35% • Sarcomas: <1% • Lymphomas, Leukemias, and Myeloma: 9% Epithelium • A sheet of closely packed cells that line internal and external surfaces • Form secretory elements (glands):secretion of enzymes,hormones,lubricants • Form membranes Mucous:digestive,excretory,reproductive,respiratory tract Serous:body cavities Cutaneous:skin Epithelium characteristics • An epithelium is separated from other tissues by a thin,non-cellular membrane (basilar membrane) • Eplithelia are usually note in direct association with blood vessels:receive nutrients and export waste via. diffusions • Eplithelia may form single layers of cells (simple) or multiple layers of cells (stratiﬁed) • Epithelial cells are described by their shape.Three basic types: Cuboidal epithelium (square) Columnar epithelium (elongated) Squamous epithelium (ﬂat) Summary of epithelium characteristics • An epithelium is separated from other tissues by a thin,non-cellular layer called the basement membrane. • Eplithelia are usually not in direct association with blood vessels:receive nutrients and export waste via. diffusion through tissue • Eplithelia may form single layers of cells (simple) or multiple layers of cells (stratiﬁed). • Epithelial cells are described by their shape (squamous,cuboidal,columned) Cutaneous Epithelium • Epidermis (the skin's epithelium) • Dermis Connective tissue Blood vessels Lymph vessels Basal Cells • Stem cells of the skin (divides;division is a prerequisite for cancer) • Source of most of the cells in the epidermis Squamous Cells • Thick layers on palms of your hands,soles of your feet,and tips of your ﬁngers Melanocytes • Manufacture brown pigment melanin that absorbs UV irradiation • Nestled in among basal cells • Distributed to cells in the squamous layer Skin Cancers • Three types: Basal cell carcinoma ‣ Incidence (cases per year):800,000-900,000 Squamous cell carcinoma ‣ Incidence:200,000-300,000 ‣ Fatalities per year:1,000-2,000 for basal and squamous cell carcinoma combined Malignant melanoma ‣ Incidence:73,870 ‣ Fatalities per year:9,940 Skin Cancer Risk Factors • Exposure to UV light:basal,squamous,melanoma • Genetics (family history):basal,melanoma • Pre-existing skin conditions:squamous,melanoma • Chemical:squamous,melanoma UV Light Exposure • UV is relatively low energy,most absorbed by the skin • Evidence Skin cancer occurs primarily on exposed areas Skin cancer is rare in dark-skinned races Cancer incidence correlated with amount of exposure Correlated with intensity of exposure Can be induced in lab animals UV light causes mutations,with known mechanisms • Increasing trend due to: Recreational clothing exposes more skin Possible increased UV from ozone depletion More participation in outdoor activities Cultural value of darker complexion Basal Cell Carcinoma • Lifetime risk:~30% (Caucasians) • 75-80% of all reported skin cancers • Generally not included in statistics for cancer incidence • Majority cases located on face,neck,back of hands • Rarely spreads • High cure rate • Rarely fatal Squamous Cell Carcinoma • 20-25% of all reported skin cancers in the US (>200,000 cases annually) • Generally not included in statistics for cancer incidence • Low mortality rate • Can be local or regional • High cure rate
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'