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UNLV / Biology / BIOL 100 / bio 100 exam 2

bio 100 exam 2

bio 100 exam 2

Description

School: University of Nevada - Las Vegas
Department: Biology
Course: General Biology for Non-Majors
Professor: Michael webber
Term: Spring 2017
Tags: Biology
Cost: 50
Name: Bio 100 Exam #2 Study Guide
Description: These notes cover chapters 19-21a of the second exam.
Uploaded: 03/11/2017
28 Pages 208 Views 2 Unlocks
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1) Where are chromosomes found in the cell?




(2) Meiosis (2) What is a chromosome?




(1) What are the two ways in which cells divide?



Exam #2 Study Guide Chapter 19 (1) What are the two ways in which cells divide? (1) Mitosis (2) Meiosis (2) What is a chromosome? a tightly coiled combination of a DNA molecule and specialized proteins called histones (2.1) Where are chromosomes found in the cell? the cell nucleus → (2.2) histones combined with the DNA are for supporDon't forget about the age old question of elyse jenkins
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Don't forget about the age old question of structural functionalism homelessness
t and control of gene activity (3) What is a gene? a specific segment of the DNA that directs the synthesis of a protein, which in turn plays a structural or functional role within the cell (3.1) genes are arranged in a fixed sequence (3.2) genes determine the expression of a particular characteristic or trait (3.3) genes also occur in pairs the members of each gene pair are located at the same position on homologous chromosomes (4) What is a somatic cell? all cells except eggs or sperm have 46 chromosomes (4.1) Humans have 46 chromosomes= 23 pairs of chromosomes + one member of each pair comes from the mother's egg and the father's sperm (4.2) Each contain 23 homologous chromosome pairs, a pair being two chromosomes with genes for the same traits 1 of 28 a.k.a homologues (4.3) What is a diploid? any cell with two of each kind of chromosome (5) What is a sex chromosome? + one of the 23 pairs of chromosomes, that determines whether a person is male or female (5.1) What are the two types of sex chromosomes? (5.2) Someone with two X chromosomes is genetically female (5.3) Someone with an XY chromosome is genetically male (6) What are autosomes? the other 22 pairs of chromosomes (6.1) Autosomes determine the expression of most of a person's inherited characteristics (7) What is mitosis? one nucleus divides into tow daughter nuclei containing the same number and kinds of chromosomes (8) What is the cell cycle? • the entire sequence of events that a cell goes through, from its origin in the division of its parent cell through its own division into two daughter cells (8.1) how long does the cell cycle usually take? 16-24 hours (9) What is the interphase? the period of the cell cycle between cell divisions +(9.1) a time of intense preparation for cell division (9.2) the DNA and organelles are duplicated 2 of 28 (9.3) when the cell divides it creates daughter cells FCL (9.4) What are the three parts of interphase? + G1 ("first gap") + S (DNA Synthesis) G2 (“second gap") (9.5) the genetic material is in the form of long, thin threads that rare often called chromatin (9.6) the two copies, each an exact replicate of the original chromosome, stay attached to one another at a region known as the centromere (9.7) as long as the replicate copies remain attached, each copy is called a chromatid the two attached chromatids are genetically identical and are referred to as sister chromatids • (10) What are the two conditions that must be made for healthy cells to divide? (1) proteins monitor the environment within the cell to ensure that it's appropriate for cell division + (2) the DNA has been accurately replicated • What is the only exception to this rule? cancer cells (11) The division of body cells (after interphase) consists of what two processes that overlap somewhat in time? (1) mitosis, the division of the nucleus (2) cytokinesis, the division of the cytoplasm that occurs toward the end of mitosis (12) What are the four stages of mitosis? + (1) prophase + a time when changes occur in the nucleus as well as the cytoplasm 3 of 28 in the nucleus, the chromatin condenses and forms chromosomes as DNA wraps around histones the DNA forms a tightly compacted structures during this no replication and gene activity is shut down + chromosomes condense • (2) metaphase + the chromosomes attach to the mitotic spindles, forming a line at what is called the equator (center) of the mitotic spindles + chromosomes (consisting of two chromatids) line up at equatorial plate (3) anaphasse begins when the sister chromatids of each chromosomes begin to separate, splitting at the centromere + the attachments between sister chromatids break + (4) telophase + a nuclear envelope forms around each group of chromosomes at each pole, and the mitotic spindle disassembles new nuclei form, each with two complete sets of chromosomes cytokinesis divides cell into two daughter cells (13) What are karyotypes? chromosomes numbered form largest to smallest + (13.1) can be checked for irregularities in number or structure of chromosomes (14) How do gametes-eggs or sperm differ from somatic cells? they are haploid (14.1) What is a haploid? → indicate by n; they have only one number of each homologous pair of chromosomes • (15) What is meiosis? Study Soup of 4 of 28 • two divisions that result in up to four haploid daughter cells (15.1) Gametes are produced by a type of cell division called meiosis (15.2) What are the functions of meiosis? keeps the number of chromosomes in a body cell constant from generation to generation increases genetic variability in the population (16) What are the steps of Meiosis I? • produces two cells, each with 23 chromosomes is the separation of homologous chromosomes occurs reliably members of homologous pairs line up next to one another by a phenomenon called synapsis (16.1) what is synapsis? + “bringing together” + interkinesis (16.2)What is interkinesis? a brief interphase like period homologous chromosomes separate into two haploid cells, each containing one member of each homologous pair (17) What are the steps of Meiosis II? sister chromatids separate, and four haploid daughter cells are formed that may develop into gametes in males, one diploid cell can result in four functional sperm in females, meiotic divisions of one diploid cell result in only one functional egg and up to three nonfunctional cells called polar bodies (18) What are the differences between mitosis and meiosis? mitosis involves one cell division 5 of 28 process two diploid cells + occurs in somatic cells results in growth and repair no exchange of genetic material daughter cells are genetically similar meiosis involves two cell divisions produces up to four haploid cells occurs only in ovaries and testes during the formation of gametes (egg and sperm) • results in gamete (egg and sperm) production parts of chromosomes are exchanged in crossing over • daughter cells are genetically dissimilar (19) What is crossing over? corresponding pieces of chromatids of maternal and paternal homologues (nonsister chromatids) are exchanged during synapsis when the homologues are aligned side by side (19.1) afterwards; the affected chromatids have a mixture of DNA from the two parents (19.2) increases the genetic variability of gametes (20) What is independent assortment? a second way that meiosis provides for the shuffling of genes between generations (20.1) the relative positioning of homologous maternal and paternal chromosomes with respect to the poles of the cell is random (20.2) the members of each homologous pair orient independently of the other pairs • (21) What is nondisjunction? 6 of 28 dy So the failure of homologous chromosomes to separate during meiosis I or of sister chromatids to separate during meiosis II • (21.1) What is the difference between trisomy and monosomy? + trisomy- the condition in which there are 3 representatives of 1 chromosomes monosomy- the condition in which there is only one representative of a particular chromosome in a cell are severe enough to cause the death of the fetus, which will result in a miscarriage (22) What is a syndrome? • a group of symptoms that generally occur together (22.1) What are the different types of syndromes? • Turner Syndrome-occurs in individuals who have only a single X chromosomes (XO) • has the external appearance of a female may have thick fold of skin on the neck + noticeably short + chest is wide and underdeveloped breast + ovaries are poorly developed, leading to infertility Klinefelter Syndrome- is observed in males who are XXY an extra X chromosome is twice as likely to come from the egg + is fairly common not all XXY males display these symptoms: testes remain small and don't produce an adequate amount of the male sex hormone (testerone) taller than average (but less muscular) • breasts may slightly develop • testes may not produce sperm, which leads to sterile 7 of 28 + Triple-X Syndrome- a female with 3 X chromosomes have abnormal sexual development and are able to conceive children some have learning disabilities and delayed language skills Jacob Syndrome- a male with 2 Y chromosomes + produced when the chromatids of a replicated Y chromosomes fail to separate often taller than normal, and some have slightly lower than normal intelligence + Down Syndrome-born with 3 copies of chromosome 21 + a.k.a trisomy 21 symptoms of down syndrome: moderate to severe mental impairment • short stature or shortened body parts (due to poor skeletal growth) typically have flattened nose a forward-protruding tongue that forces the mouth open upward-slanting eyes + a fold of skin at the inner corner of each eye the risk of having a baby with Down Syndrome increases with the mother's age Chapter 20 (1) What is a gene? e d irects the synthesis of a specific protein that can play either a structural or a functional role in the cell (2) What are alleles? different versions of a gene 8 of 28 + (2.1) alleles produce different versions of the trait they determine (2.2) What is the difference between homozygous and heterozygous alleles? homozygous-individuals with two copies of the same allele of a gene homo= same zygo= joined together heterozygous- individuals with different alleles of a given gene heteror different zygo= joined together (2.3) What is the difference between dominant and recessive alleles? + dominant allele- when the effects of a certain allele can be detected regardless of whether an alternative allele is also present recessive allele- an allele whose effects are masked in the heterozygous condition + (2.4) What are the designated signs for dominant and recessive alleles? dominant allele-capital letter recessive allele-lowercase letter (2.5) What is a genotype? the precise set of alleles a person possesses for a given trait or traits + it tells us whether the individual is homozygous or heterozygous for a given gene + (2.6) What is a phenotype? the observable physical trait or traits of an individual (3) What is the law of segregation? during the production of gametes the two copies of each hereditary factor segregate so that offspring acquire one factor from each parent explains how, for every gene in our chromosomes, one of the alleles comes from our mother and one comes from our father 9 of 28 (4) What is the law of independent assortment? when two or more characteristics are inherited individual hereditary factors assort independently during gamete production, giving different traits an equal opportunity of occurring together explains why the mixture of alleles that came from the mother and alleles that came from the father is different in every gamete (5) Who is Gregor Mendel? a monk, whose ideas are used today to predict the outcome of hereditary crosses (6) What is a one-trait crosses? consider the inheritance of a single trait (7) What is a Pungent Square? + a diagram used to predict the genetic makeup of the offspring of individuals of particular genotypes columns are set up and labeled to represent each of the possible gametes of one parents + (8) What are two-trait crosses? predict the probable outcome for inheritance of two traits of interest (8.1) What is a dihybrid cross? a mating of individuals who are both heterozygous for two traits of interest (9) What is a pedigree? a chart showing the genetic connections between individuals in a family +(9.1) What is an autosomal dominant? • inheritance of genetic (9.2) What is an autosomal recessive? genetic disorders caused by recessive alleles on a pair of non-sex chromosomes 10 of 28 + (10) What is the difference between complete and incomplete dominance? complete dominance- a situation in which a heterozygous individual exhibits the trait associated with the dominant allele but not that of the recessive allele incomplete dominance-the expression of a trait in a heterozygous individual is somewhere between the expression of the trait in a homozygous dominant individual and the expression of the trait in a homozygous recessive individual + (11) The inheritance of type AB blood is an example of codominance (12) What is pleiotropy? one gene leading to many effects (13) What are multiple alleles? when 3 or more forms of a given gene exist + (14) What is polygenic inheritance? the involvement of 2 or more genes, often on different chromosomes, in predicting a trait (14.1) the more genes involved, the smoother the gradations and the greater the extremes of trait expression (15) Genes that tend to be inherited together are described as being linked (15.1) Linked genes usually don't assort independently (16) What are X-linked genes? most genes on the X chromosome have no corresponding alleles on the Y chromosome (16.1) the recessive phenotype of X-linked genes is much more common in males than in females a son cannot inherit an X-linked recessive allele from his father a daughter, however, can inherit an X-linked recessive alley from either parent (16.2) What are the disorders caused by X-linked recessive alleles? red-green color blindness 11 of 28 two forms of hemophilia • Duchenne muscular dystrophy (17) What is the cause of breakage among chromosomes? + certain chemicals, radiation, or viruses (18) What is the difference between deletion and duplication? deletion-the loss of a piece of chromosome • duplication- the addition of a piece of chromosome S (19) What is the most common type of deletion? o ccurs when the tip of a chromosome breaks off and then, during cell division, doesn't move into the same daughter cell as the rest of the chromosome (20) What happens when you delete more than a few genes on an autosome? is usually lethal • (21) The loss of small regions, due to deletion, can cause disorders (22) Cri-du-chat syndrome is an example of deletion + (22.1) What is Cri-du-chat syndrome? + "cry of the cat"; caused by the loss of a small region near the tip of chromosome 5 + (23)What is Fragile X Syndrome? an abnormally long sequence of repeats caused by duplication makes the X chromosome fragile and easily broken the most common form of inherited mental impairment (24) What are the two procedures available for diagnosing genetic problems in the fetus? amniocentesis- a needle is inserted through the lower abdomen into the uterus, and a small amount of amniotic fluid is withdrawn Study Soup Of (2) chorionic villi sampling (CVS)- removes and analyzes a small amount of tissue containing chorionic villi, the small, fingerlike projections of the part of the placenta called the chorion 12 of 28 Chapter 21: (1) DNA is sometimes called the thread of life + (2) What is DNA? + a double-stranded molecule resembling a ladder that is gently twisted to form a spiral called a double helix + (2.1) What does DNA stand for? + Deoxyribonucleic Acid + (2.2) Each side of the ladder is made from a string of repeating subunits called nucleotides → (2.3) What is a nucleotide? composed of the subunits, including one sugar, one phosphate, and one nitrogenous base (2.4) What are the four nitrogenous bases of DNA? + Adenine (A) + Thymine (T) • Guanine (G) Cytosine (C) (2.5) The sides of the ladder are composed of alternating sugars and phosphate; the rungs consist of paired nitrogenous bases → (2.6) Explain the concept of complementary base pairing. Adenine (A) only pairs with Thymine (T) + Cytosine (C) only pairs with Guanine (G) (2.7) Complementary base pairings are held together by weak hydrogen bonds (2.8) The DNA within each human cell has how many base pairs? + 3 billion base pairs + (3) What is Nuclei Acid? Study Soup 13 of 28 + a molecule formed by the joining of nucleotides (3.1) DNA is a nucleic acid + (4) DNA is copied before mitotic and meiotic cell division (5) What is the process of DNA replication? Study Soup 1. DNA replication, begins when an enzyme breaks the weak hydrogen bonds that hold together the paired bases that make up nucleotide strands of the double helix, thereby "unzipping" and unwinding the strands 2. the nitrogenous bases on the separated regions of each strand are temporarily exposed 3. free nucleotide bases, can then attach to complementary bases on the open DNA strands 4. DNA Polymers enzymes that link the sugars and phosphates of the newly attached nucleotides to form a new strand 5. As each of the new double-stranded DNA molecules forms, it twists into a double helix 6. Semiconservative replication in each of the new double-stranded DNA molecules, one original (parent) strand is saved (conserved) and the other (daughter) strand is new (6) DNA directs the synthesis of ribonucleic acid (RNA) (6.1) What is ribonucleic acid? * directs the synthesis of a polypeptide ( a part of a protein) or a protein + (7) What is a gene? • a segment of DNA that contains the instructions for producing a specific protein (or, in some cases, a specific polypeptide) (7.1) What is the process of gene expression? DNA-> RNA-> Protein 14 of 28 (8) RNA is the intermediary that comes the information encoded in DNA from the nucleus to the cytoplasm and directs the synthesis of the specified protein (9) RNA is composed of nucleotides linked together: • Uracil (U) pairs with Adenine (A) • (10) What transcription? the first step in converting the DNA message to a protein by copying the message as RNA DNA->RNA (11) How are DNA and RNA similar? are nucleic acids are composed of link nucleotides • have a sugar-phosphate backbone have 4 types of bases (12) How are DNA and RNA different? DNA + is a double-stranded molecule has a sugar deoxyribose • contains the bases adenine, guanine, cytosine, and thymine functions primarily in the nucleus * RNA is a single-stranded molecule has a sugar ribose contains the bases adenine, guanine, cytosine, and uracil functions primarily in the cytoplasm (13) What are the three types of RNA produced in cells? + (1) Messenger RNA (mRNA)- carries DNA's information in the sequence of its bases (condons) from the nucleus to the cytoplasm 15 of 28 • (2) Transfer RNA (TRNA)-binds to a specific amino acid and transports it to be added, as appropriate, to a growing polypeptide chain (3) Ribosomal RNA (TRNA)- combines with protein to form ribosomes (structures on which polypeptides are synthesized) (14) What is the process of transcription? (1) the segment of DNA to be transcribe unwinds (2) RNA nucleotides pair with the complementary DNA bases and are linked together to form an RNA transcript (3) The RNA transcript is released from the DNA (14.1) What is a promoter? the signal to start transcription is given by a specific sequence of bases on DNA (14.2) What is an RNA polymerase? enzyme that binds with the promoter on DNA and then moves along the DNA strand (15) These unexpressed regions of DNA are called introns, short for intervening sequences + (16) The remaining segments of DNA or mRNA, called exons for expressed sequences, splice together to form the sequence that directs the synthesis of a protein (17) What is translation? + converts the nucleotide language of mRNA into the amino acid language of a protein + RNA-> Protein (18) What is genetic code? the "language" of genes that translates the sequences of bases in DNA into the specific sequences of amino acids in a protein (18.1) What are codons? 16 of 28 sequences of three bases on mRNA that specify 1 of the 20 amino acids or the begging or end of the protein chain (19) The four bases in RNA (A,U,G,C) could form 64 combos of 3-base sequences (19.1) the number of possible codons, therefore, exceeds the number of amino acids + (20) What are the stop codons? UAA, UAG, UGA they do not code for an amino acid (21) A tRNA molecule must be able to recognize both the codon on mRNA and the amino acid that the codon specifies (21.1) How does the tRNA know the correct location along mRNA? • its determined by the anticodon, a sequence of three nucleotides on the tRNA (21.2) What is the role of the anticodon? it "reads” the language of mRNA by binding to a codon on the mRNA molecule according to the complementary base-pairing rules (22) What is a ribosome? consists of 2 subunits (small and large), each composed of ribosomal Ran (rRNA) and protein (22.1) The subunits form in the nucleus and are shipped to the cytoplasm (22.2) What is the role of the ribosome in protein synthesis? to bring the tRNA bearing an amino acid close enough to the mRNA to interact (23) What are the three stages of translation? (1) Initiation- the major players in protein synthesis (mRNA, TRNA, and ribosomes) come together • What are the steps of initiation? 1. the small ribosomal subunit joins to mRNA at the start codon, AUG 17 of 28 2. A tRNA with complementary anticodon pairs with the start codon. Ribosomal subunits join to form a functional ribosome (2) Elongation- of the protein occurs a additional amino acids are added to the chain • What are the steps of elongation? • 1. codon recognition with the start codon positioned in one binding site, the next codon is aligned in the other binding site 2. peptide bond formation + enzymes link the amino acids 3. ribosome movement the tRNA in the first binding site leaves the ribosome the ribosome moves along the mRNA, exposing the next codon + enzymes link the amino acids the process is repeated many times (3) Termination-occurs when a stop codon moves into the ribosome • What are the steps of termination? 1. stop codon moves into ribosome 2. parts disassemble (24) What is a polysome? • a group of ribosomes reading the same mRNA molecule (25) What is a mutation? • a change in DNA (25.1) What are the different types of mutations? Point Mutations-changes in one or a few nucleotide changes ; error in pairing during replication 18 of 28 + Insertion-adding bases + Deletion-losing bases + insertion and deletion often cause more serious effects than point mutations Inversion- flipping of nucleotide position • Duplication- complete copies of genes •Silent Mutation-codes for the same amino acids • Harmless Mutations- changes amino acids in the sequence, but the change does not affect protein function (26) Gene activity is affected by the coiling and uncoiling of the DNA: coiled= non expressed gene uncoiled= active gene • (27) What is a promoter? + a specific sequence of DNA that is located adjacent to the gene it regulates (28) What are transcription factors? regulatory proteins binds to a promoter, which in turn allows RNA polymerase to bind to the promoter begins transcription of the regulated genes can also bind to enhancers (29) What are enhancers? segments of DNA that increase the rate of transcription of certain genes specify the timing of expression, a gene's response to external signals, and developmental cues that affect gene expression (30) What is Genetic Engineering? the manipulation of genetic material for human purposes + is part of biotechnology 19 of 28 (30.1) What is biotechnology? a field in which scientists make controlled use of living cells to perform specific tasks (31) What is recombinant DNA? • DNA combined from two or more sources (31.1) What are the steps of recombinant DNA? (1) the gene of interest is sliced out of its original organism and spliced into vector DNA + (2) The vector is used to transfer the gene of interest to a new host cell vector-biological carriers that ferry the recombinants DNA to a host cell plasmid- a small, circular piece of self-replicating DNA that exists separately from the bacterial chromosome; a common vector (3) The recombinant organism containing the gene of interest is identified and isolated from the mixture of recombinants (4) The gene is amplified through bacterial cloning or by use of a polymerase chain reaction + (32) What are the 2 techniques for accomplishing gene amplification? (1) cloning- a group of genetically identical organisms all descended form a single cell all members carry the same recombinant DNA (2) polymerase chain reaction (PCR) • What are the steps of polymerase chain reaction (PCR)? (1) the DNA of interest is unzipped by gentle heating, to break the hydrogen bonds and form single strands • (2) the templates are mixed with primers, nucleotides, and DNA polymerase + primers- special short pieces of nucleic acid 20 of 28 (3) the mixture is called to allow for base pairing + (4) complementary DNA strands form on each template strand. The amount of DNA is now doubled (5) Repeat Procedure: the amount of DNA is doubled again (33) What are the two ways genetic engineering has been used? (1) genetic engineering provides a way to produce large quantities of a particular gene product • (2) genetic engineering allows a gene for a trait considered useful by humans to be taken from one species and transferred to another species (34)What is a Bovine somatotropin (BST)? U . a result of genetically engineered bacteria; a hormone naturally produced by a cows pituitary gland that enhances milk production (35) What is pharming? faming + pharmaceuticals (35.1) What are the steps of pharming? (1) inject the human gene of interest into a donor cell (2) implant the cell into the host mother (3) identify transgenic offspring with the gene of interest by PCR (4) the gene of interest is expressed in the cells of mammary glands, and the protein is secreted in milk (5) collect the milk (6) separate the milk proteins (7) isolate the useful protein (36) What is Gene Therapy? its goal is to cure genetic diseases by putting normal, functional genes into the body cells that were affected by the mutant gene (36.1) What are the methods of delivering a healthy gene? (1) incorporate a healthy form of the gene into the virus 21 of 28 + (2) remove bone marrow stem cells form the patient (3) infect the patients stem cells with the virus that is carrying the healthy form of the game (4) return the genetically engineered stem cells to the patient. The gene is expressed to produce the needed protein (37) What is a retrovirus? + a virus whose genetic information is stored as RNA rather than DNA + another type of virus used in gene therapy once inside the target cell, it rewrites its genetic information as double stranded DNA and inserts the viral DNA into a chromosome of the target cell (38) More than 4,000 human diseases have been traced in single genes (39) The first condition to be treated experimentally with gene therapy is a disorder referred to as severe combined immunodeficiency disease (SCID) which is caused by a mutant gene that prevents the production of an enzyme called adenosine deaminase (ADA) (40) What is a genome? the entire set of genes carried by one member of a species (41) What are genomics? the study of entire genomes, and the interactions of the genes with one another and the environment (42) The Human Genome Project, is a worldwide research effort, completed in 2003, to sequence the human genome (42.1) What are the results of the Human Genome Project? the location of genes along all 23 pairs of human chromosomes the sequence of the estimated 3 billion base pairs that make up those chromosomes + humans are identical in 99.9% of the sequences of their genes . (43) What is epigenome? 22 of 28 consists of chemicals that bind to specific genes and turn them on or off its flexible • often plays a role in disease and cancer (44) Microarray, consists of thousands of DNA sequences stamped onto a single glass slide called a DNA chip (44.1) How do researchers use microarrays? • to monitor large numbers of DNA segments to discover which genes are active and which are turned off under different conditions * (44.2) It is useful in identifying genetic variation in the members of a population (44.3) some of the genetic differences are in the form of single-nucleotide polymorphisms (SNPs, or snips) (44.4) What is a haplotype? • a group of SNPs in a region of a chromosome + (45) We (humans) share 50% of our genes with the fruit fly and 90% of our genes with the mouse Chapter 21a: (1) What is a tumor (or neoplasm)? an abnormal growth of cells that form a mass of tissue (1.1) neoplasm="new growth” (1.2) What is the difference between a benign and malignant tumor? benign tumor- an abnormal mass of tissue that is surrounded by a capsule of connective tissue and that usually remains at the site where it forms • its cells don't invade surrounding tissue or spread to distant locations • the tumor can (and does) grow can be removed surgically 23 of 28 can still be dangerous because they can press on nearby tissues enough to interfere with the functioning of those tissues + malignant tumor- an abnormal mass of tissue that can invade surrounding tissue and spread to multiple locations throughout the body +(1.3) What is metastasis? the spread of cancer cells from one part of the body to another (2) What are the stages of cancer development? + (1) initial tumor cell (2) cell divides more frequently than others carcinoma in situ- tumor remains at its site of origin (3) cells of the tumor release growth factors to attract a blood supply (4) cells of malignant tumor: attract a blood supply, gain the ability to leave the other cells, spread to distant sites (metastasize) + (3) Cancer cells are greedy, they deprive normal cells of nutrients + (4) What is dysplasia? the changes in shape, nuclei, and organization within tissues of precancerous cells (5) The tumors that form in distant sites in the body are responsible for 90% of the deaths of people with cancer (6) Once cancer cells have separated from the original tumor, they usually enter the cardiovascular or lymphatic system (7) What are the two types of genes that usually regulate cell division? (1) proto-ncogenes stimulate cell division + a mutation can destroy the regulation of cell division + oncogene-a mutated proto-ncogenes 24 of 28 it increases cell division with or without a stimulus (2) Tumor-suppressor genes inhibit or stop cell division p53- the tumor-suppressor gene that produces a protein that regulates another gene whose job it is to make a protein that keeps cells in a non dividing state a mutated p53 tumor-suppressor gene, is often responsible for cancer • cancers containing mutations in p53 are difficult to kill with radiation or chemotherapy (8) ras, gene normally signals the presence of a growth factor, which stimulates cell division (8.1) What is a ras oncogence? a protein that is eractive and stimulates cell division even in the absence of growth factors (9) What is contact inhibition? + if healthy cells contact a neighbor, they stop dividing +(9.1) Cancer cells do not exhibit contact inhibition • (10) What is apoptosis? when cells activate a genetic suicide program in response to a biochemical or physiological signal (10.1) prompts cells to manufacture proteins that then kill the cells during this, the outer membrane of the condemned cell produces bulges, called blebs • (10.2) What are blebs? are pinched off the cell; indicate that the cell will break down into membrane-enclosed fragments that are engulfed and removed by other cells (11) What is senescence? 25 of 28 the nondividing state of a cell (12) What are telometers? + pieces of DNA at the tips of chromosomes that protect the ends of the chromosomes (12.1) when telometers are completely gone, the cell dies (12.2) it's length serves as a gauge of cell's age (13) Normal cells are "glued" in place by special molecules on their surfaces called cellular adhesion molecules (CAMs) (13.1) one way cancer cells break loose is by, secreting enzymes that break down the CAMs, that hold them and their neighbors in place (14) Multiple mutations help spread cancer: The first mutation occurs and is passed on to all the descendent cells + The second mutation occurs in one of the descendent cell containing the original mutation (15) Damage must occur in at least two genes before cancer occurs + (16) A person who inherits only one mutant gene may be predisposed to cancer (17) Epigenetic processes are also irreversible + (18) What is Cancer Stem Cell Hypothesis? only a subpopulation of cells within the tumor, cancer stem cells, have the capacity for unlimited self-renewal and give rise to the tumor + (19) What are the known causes of cancer? + (1) viruses cause about 5% of cancers in the U.S. (2) chemicals carcinogen- an environmental agent that fosters the development of cancer some chemicals cause cancer by producing mutations or by stimulating cell division 26 of 28 + certain hormones (like estrogen) promote cancer (3) radiation it can lead to cancer by causing mutations in DNA (20) What is carcinomas? cancers of the epithelial tissues (21) What is leukemias? cancers of the bone marrow (22) What is sarcomas? cancers of the muscle, bone, cartilage, or connective tissues (23) What is lymphomas? cancers of the lymphatic tissues + (24) What is adenocarcinomas? cancers of the glandular epithelia + (25) What are ways you can reduce risk of cancer? (1) don't use tobacco (2) reduce saturated fat in your diet (3) minimize your consumption of salt-cured, picked, and smoked foods + (4) eat at least 5 servings of fruit/vegetables every day (5) avoid excessive alcohol intake (6) watch your caloric intake, and maintain a healthy body weight (7) avoid excessive sunlight + (8) avoid unnecessary medical x-rays (9) have the appropriate screening exams on a regular basis (26) What does the acronym CAUTIONS stand for? + Change in bowel or bladder habit or function • A sore that doesn't heal 27 of 28 • Unusual bleeding or bloody discharge + Thickening or lump in breast or elsewhere Indigestion or difficulty swallowing Obvious change in wart or mole Nagging cough or hoarseness (27) What are the ways you diagnose cancer? (1) routine screening can be performed yourself or by medical professional + (2) Imaging si (3) Biopsy- the removal and analysis of a small piece of tissue suspected to be cancerous; often done using a needle + (4) tumor marker tests (5) genetic tests (28) What are the different ways to treat cancer? (1) surgery (2) radiation + (3) chemotherapy + (4) targeted cancer treatment (5) immunotherapy + (6) inhibition of blood vessel formation (7) gene therapy|| 28 of 28

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