This Powerpoint contains information for chapters 11, 12, and 13.

Gene Expression Role Activation of gene = ____________________ When transcription occurs Mechanisms ensure that each protein is produced only when needed 2 steps = ____________________ ____________________

Gene Expression in Prokaryotes Francois Jacob and Jacques Monod Discovered how genes control metabolism of sugar lactose E. Coli See Concept Map

Gene Expression in Eukaryotes Vastly different from prokaryotes Larger ______________ DNA located in several individual chromosomes instead of single circular one Most are __________________________________ Expression is far more complex No _______________ found in eukaryotes

Three regulatory elements: Structural genes: ____________________ Promoter: __________________________ Operator: __________________________ All three of the above terms form the _______________________________ What is the lac operon?

Let’s talk about E. coli Lactose…found in cows milk…disaccharide (glucose + galactose) Let’s say you drink a glass of milk: Lactose entering your body _______________________________________________ Control the metabolism of lactose Adjacent on chromosome Production is controlled by 3 regulatory elements

Repressor attaches to operator

If lactose is absent… Repressor protein attaches to ____________ Inhibits a specific gene from being expressed Prohibits ______________from binding to structural genes = no _______________

Jobs on structural genes Introns – _________________________________ Exons – __________________________________ Unsure of benefits of intron-exon pattern May provide options for producing different _________ Could facilitate the exchange of exons among homologous chromosomes during crossing over in meiosis = _________________________ Pattern could serve as an additional source of the genetic diversity that is essential for evolution

Control after transcription Gene expression can be controlled by modifying _____ after _________________________ __________ – lg. molecule; from transcription of introns and exons Enzyme comes in and splits the pre-mRNA at each end of an intron and then splices the exons together, forming ________________ mRNA leaves nucleus and enters the cytoplasm mRNA begins the manufacturing of proteins on the ribosomes BUT WE ALREADY KNOW THIS!!!!

Nature of Cancer Tumor – uncontrolled, abnormal cell division Benign – ________________________________________________ ________________________________________________ Malignant – _____________________________________ Metastasis – ____________________________________

Kinds of cancer Carcinomas – _______________________________________________ _______________________________________________ Sarcomas – ____________________________________ Lymphomas – solid tumors that grow _______________________________________________ _______________________________________________ _______________________________________________

Cancer and the cell cycle Normal cell division – divide when needed and when conditions are right; governed by ___________________________________________ ___________________________________________ Adequate nutrition Attachment to other cells, membrane, or fibers between cells Cancer cell division – continue to divide in dense environments _____________________________________________ Continues to divide after _______________________________________________

Causes of cancer Mutations that alter the expression of genes coding for growth factor proteins Can be ________________________ Mostly caused by ________________________________________________ ________________________________________________ Depends on factors Maybe genetic predisposition (mutations in gametes can be passed to offspring) Exposure time to _______________ Amount of ____________________ More than one ________________ is usually needed to produce cancer

Oncogenes Begin as _______________– normal genes; control cell growth and differentiation Normally code for ______________ Regulate ________________________________________ Mutation in proto-oncogene Produce more ________________________________________________ ________________________________________________ Increases rate of cell cycle = ___________________

Tumor-suppressor genes Code for ________________________________ Mutations = proteins for which they code are either expressed _______________________________________________ _______________________________________________ _______________________________________________

Viruses and Cancer Many viral genes are ________________ Viruses can stimulate _________________by causing _______________________________________________ _______________________________________________ Viruses may activate the cell’s own _________________ Found to cause various types of ___________________

Review Know all vocabulary (would you expect anything less?) you know, morphogenesis, homeoboxes, introns, exons, etc. Know the pictures depicting gene expression in prokaryotes and eukaryotes and what is happening (be able to identify what is happening and where; steps) make sure you understand the lac operon! steps leading to formation of protein in eukaryotic cells Know difference between oncogene and tumor- suppressor gene Know how Drosophila is used as an example with regards to mutations. Know how genes can be expressed – the process Know types of cancer and what happens for a cell to become cancerous

Sex Determination Thomas Hunt Morgan Studied __________________ 4 Pairs of ______________________________ Noticed one pair was different between males and females X – appeared same in male and females Y – shorter, hook shaped Gametes from meiosis II have either ____________________(depending on sex of parent)

Sex Determination (cont.) Morgan believed ____________________ it to carry more genes X = X-linked genes Y = Y-linked genes Genes on sex chromosomes = ___________________ Morgan’s fruit fly experiments confirmed the existence of X-linked traits

Morgan’s findings on eye color White-eyed male x red-eyed female = (followed Mendel’s predictions) F 1 generation all had __________________ Crossed F 1 generation = F 2 generation exhibited _______________________________________________ Hypothesized that the gene for _______________________________________________ _______________________________________________

Linkage groups Linked genes tend to be ___________________ Typically a _______ ratio If on a different chromosome, they are _________________ Key: Grey (G) is _______________ to black (g); Long (L) is ____________________ to short (l) Morgan crossed: GGLL x ggll F 1 = GgLl; crossed two F 1 generations F2 = Morgan thought if alleles were on different chromosomes, should _______________________ Phenotypic ratio should be ____________ If on same chromosome, __ gray, long-winged: __ black, short-winged Result closely approximated the ___________ Hypothesized that genes are linked

What about … Gray, short-winged and black, long-winged appearing? If on same chromosome, must be some kind of _______________________________ Possibly couldn’t be ________________ = Occur in one individual out of tens of thousands Rearrangement occurred during _________________ Rearrangement of alleles = _____________________________________________________ _____________________________________________________ _____________________________________________________

Chromosome Mapping Alfred H Sturtevant Morgan’s student Used ________________________________________________ ____________________________________of Drosophila Know what a chromosome map is, you won’t have to calculate map units, etc.

Mutations Chg in DNA of organism Entire ________________ or single ___________________ Germ Cell = _______________________________________________ _______________________________________________ Somatic = ______________________________________ Lethal = death, often before birth Beneficial? = better chance of reproducing and have evolutionary advantage Variation upon which natural selection acts

Chromosome Mutations Deletion= _____________________________________ Inversion= ____________________________________ Translocation= ________________________________ Nondisjunction= _______________________________ Ex. ____________________________________________

Gene Mutations Point = substitution, addition, or removal of Substitutions = __________________________________ Nucleotide Insertions – ________________________________ Nucleotide Deletions - ________________________________ Frame-shift = __________________________________ What happens?

12.2 (Page only) Familiarize yourself with Table 12-3 on page 230 Disorders due to _________________________ Can cause gametes to lack a ________________________________________________ Zygotes (______________) can have either 45 or 47 (often __________) 45 = ____________________ (one copy of chromosome) 47 = ____________________ (three copies)

Trisomy Trisomy 21 = extra copy of _______________________= Down Syndrome List 5 characteristics:

Down Syndrome

Nondisjunction and sex chromosomes Males with extra copy of _____ = __________________________________________________ Some feminine characteristics Some are mentally retarded Some are infertile Individuals that inherit ______________do not survive = ___________contains information essential for development Individuals that have __________________= Turner’s syndrome Female appearance Do not mature sexually infertile

Klinefelter’s Syndrome

Turner’s Syndrome

DNA Technology Used to _______________________________________________ _______________________________________________ Trace the path of the restriction enzyme using 5 post- its…be able to explain what is happening. Use your text, pages to better gain an understanding for your explanation.

How does it all happen? DNA is a long chain of _______________________ _________________________________ cut DNA into more manageable segments ___________________ are created Readily bind to _____________________________________ Can be used to isolate a _________________________ A __________________can transfer the gene to an organism

Transplanting Genes What would be the need to transplant genes? Talk with your table and discuss.