1 Syllabus Information: Genetics BIOL 3313 Dr. David F. GilmoreOffice: 418 LSE Web page: Office hours: Thursday 1:00 – 3:30, Friday 8:30- 11:00; other times by appt. Text: Essentials of Genetics 5 th edition by Klug and Cummings

2 Syllabus info (continued) Four lecture exams (100 pts each) Fifth exam at Finals time (100 pts) Additional points for homework, quizzes, other assignments. Roll call/attendance sheet Assignment for this week: Chapters 1 and 2 These PowerPoints: Note number, take scant notes; slides will be posted before class. Class attendance is required.

3 Genetics : the Study of Biological Information How is the information stored? How is it used? How is it transmitted to new generations? How is it distributed among populations?

4 Genetics : the Study of Biological Information How is the information stored? How is it used? Look at the information storage molecule itself. Look at how the information is processed and the products of that information.

5 Genetics : the Study of Biological Information How is it transmitted to new generations? How is it distributed among populations? Look at how information is passed on at the cellular level. Look at patterns of inheritance, how information is passed on and expressed at the organismal and population levels.

6 4 Major Divisions/Approaches in Genetics Classical genetics: look at patterns of inheritance, note how genes act by observing inherited characteristics. Molecular genetics: Reductionist approach, determine how genes work by examining and manipulating their molecular structure. Population genetics: Use of statistics and math to see how traits are passed on, maintained, or lost among large numbers of individuals. Cytogenetics: learning about inheritance by studying cell structures, particularly chromosomes.

7 A Book on How to Make Gargoyles: An analogy about genetic information

8 Questions about the book itself: color, weight, # of pages? Book as source of information: organization? Number of chapters? Information independent of book

9 A Book on How to Make Gargoyles: An analogy about genetic information Phenotype vs. genotype: what’s on your friend’s roof? Vertical vs. horizontal transmission: who gets a copy of the book?

10 Using genetic information: the “central dogma” Proteins can be directly responsible for traits. Enzymes (proteins) can create traits: metabolize sugars; synthesize pigments or vitamins; assemble other informational macromolecules like polysaccharides.

11 Review of cellular chemistry Lipids: components of membranes; hormones. Carbohydrates: mono thru polysaccharides, structural molecules and tags on cell surfaces. Proteins: polymers of amino acids, direct result of DNA information. Primary, secondary, tertiary, and quaternary structures. Nucleotides/nucleic acids: 3 part monomers assemble into ultimate informational molecules.

12 Review of Cell Structure Eukaryotes: larger, and compartmentalized –Feature membrane-bound organelles –DNA enclosed in nucleus, associated with histones Capable of being tightly packaged Prokaryotes: small and structurally simple –Membrane-bound organelles lacking –DNA loosely packaged with histone-like proteins Never tightly packaged Attached to inside of cell membrane

13 Eukaryotic cell surface features All cells have a phospholipid/protein bilayer membrane, the interface between the cell and its environment. The cell coat consists of informational molecules, polysaccharides and PS-containing lipids and proteins. These molecules act as receptors to identify the cell or receive messages that trigger changes in gene expression. Green: proteins; blue: PS; red: lipids.

14 The Nucleus and Cytoplasm Organelle with a double membrane Pores allow passage of materials. DNA packaged with proteins = Chromatin diffuse, granular apperance. Nucleolus : rRNA and ribosome synthesis / calnet/cellbio/page4.htm / calnet/cellbio/page4.htm; Cytoplasm is a colloid of protein and water Contains the other organelles and membrane systems such as endoplasmic reticulum and the ribosomes, site of protein synthesis.

15 More organelles Ribosomes, endoplasmic reticulum, and Golgi work together to create and distribute proteins –After synthesis on ribosomes, proteins acquire sugar tags in ER and are sorted and shunted after being prepared in Golgi. Ancient endosymbionts –Mitochondria resemble Gram negative bacteria (2 membranes) in many ways, are self replicating and have own DNA Site of aerobic respiration, ATP synthesis DNA is circular like bacterial; bacterial-type ribosomes. –Chloroplasts similar and carry out photosynthesis; have own DNA

16 Centrioles and cytoskeleton The centrioles are structures that occur in pairs and are made of microtubules. –Microtubules are made of protein –Centrioles help assemble the spindle to which chromosomes attach in mitosis. The cytoskeleton is made of microtubules and microfilaments –Proteins are generally tubulin or actin –Provides cell shape, structure and locomotion. cell.sio2.be/noyau/4.phpcell.sio2.be/noyau/4.php ; cells/cytoskel.htmwww.cellsalive.com/ cells/cytoskel.htm

17 Prokaryotes No organelles, little or no cytoskeleton Cell wall surrounding cell membrane, so membrane surface not heavily involved in receiving signals. Small size and lack of nucleus allow rapid responses to changes in the environment. Ribosomes plentiful, but smaller and different from eukaryotic.